BIOPSYCHOLOGY Flashcards
Define nervous system
Consists of the central nervous system and the principle nervous system.
Communicates using electrical signals
What is the primary internal communication system
The nervous system
What are the two main functions of the nervous system
To collect, process and respond to information in the environment.
To co-ordinate the working of different organs and cells in the body
Name the two subsystems of the nervous system
The central nervous system (CNS)
The peripheral nervous system (PNS)
Define central nervous system
Consists of the brain and the spinal cord and is the origin of all complex commands and decisions
Define the peripheral nervous system
Sends information to the CNS from the outside world, and transmits messages from CNS to muscles and glands in the body
Where is the centre of all conscious awareness
The brain
How thick is the cerebral cortex
3mM
What is the only type of organisms that have the cerebral cortex
Mammals
How is the brain divided
Into two hemispheres
How does the PNS transmit messages
Via millions of neurons
Name the two components of the PNS
Autonomic nervous system (ANS)
Somatic nervous system (SNS)
Define the autonomic nervous system (ANS)
Transmits information to and from internal bodily organs the system operates automatically.
What are the two main states sof the autonomic nervous system
The sympathetic state
The parasympathetic state
Define the somatic nervous system (SNS)
Transmits information from receptor cells in the sense organs to the CNS.
Also receives information from the CNS that directs muscles to act.
Define the endocrine system
A system that instructs glands to release hormones directly into the bloodstream.
These hormones are carried towards target organs in the body.
Which is faster the nervous system or the endocrine system
The nervous system
How does the endocrine system communicate
Via chemicals
Define gland
An organ in the body that synthesises substances such as hormones
Define hormones
A biochemical substance that circulates in the blood but only affects target organs.
They are produces in large quantities but disappear quickly.
What cells are effected by a particular hormone
The ones that have receptors for that particular hormone
Give an example of one organ and hormone affecting two places in the body
(Thyroid gland)
Thyroid gland secretes thyroxine.
Thyroxine increases heart rate by affecting cells in the heart.
Also affects cells throughout the body increasing metabolic rates - in turn affecting growth rates.
What is the key / ‘master gland’
Why
Pituitary gland
It controls the release of hormones from all other endocrine glands in the body
Which two systems often work up parallel with each other
The endocrine system and the autonomic be our system
What is an example of a situation where the endocrine system and the autonomic nervous system work together
During s stressful event
What is the first events that occur when a stressor is perceived
The Hypochampus activates the pituitary glad and this triggers activity in the sympathetic branch of the autonomic nervous system.
The ANS changes from its normal resting state (parasympathetic state) to the physiologically around sympathetic state.
What hormone takes park in the fight or flight response
Adrenalin
Outline what happens with adrenalin in the fight or flight response
Adrenaline is released from the adrenal medulla into the bloodstream.
Adrenaline triggers physiological changes in the body (e.g. increased heart rate) which creates the physiological arousal necessary for the fight or flight response
What two words describe the reaction in the body to the fight or flight response
Acute response and an automatic reaction in the body
List the 6 biological changes associated with the sympathetic response
Increased heart rate
Increased breathing rate
Dilates pupils
Inhibits digestion
Inhibits saliva production
Contracts rectum
What system returns the body to its resting state once the threat has passed
The parasympathetic nervous system
The parasympathetic and sympathetic nervous system work in ____
Opposite to each other
List the 6 biological changes associated with the parasympathetic response
Decreased heart rate
Decreased breathing rate
Constricts pupils
Stimulates digestion
Stimulates saliva production
Relaxes rectum
Define adrenalin
A hormone produced by the adrenal glands which is part of the human body’s immediate stress response system.
What are the effects of adrenalin on the cardiovascular system
What does it specifically effect and how
To what extent
Has a strong effect on the cells of the cardiovascular system - stimulating heart rate, contracting blood vessels and dilating air passages.
What is the nervous systems average response time
0.25 seconds
How long can an endocrine response take
Several seconds to days
Why is the endocrine system slower than the nervous system
Hormones have to travel through the bloodstream
How many neurons are there in the nervous system
100 billion
What percentage of neurones are located in the brain
80%
How do neuron’s provide the nervous system with its primary means of communication
By transmitting signals electrically and chemically
Define neurons
The basic building blocks of the nervous system, neuron’s are nerve cells that process and transmit messages through electrical and chemical signals
Name the three types of neuron’s in order of the direction of conduction
Sensory, relay, motor
Where do sensory neurons carry messages from and to
Carry messages from the PNS to the CNS
What are the two defining features of sensory neuron’s
Long dendrites and short axons
Where do relay neuron’s conduct impulses from and to
Connect the sensory neuron’s to the motor and other relay neuron’s
What are the two defining features of relay neurons
Short dendrites and short axons
Where do motor neurons carry impulses from and to
From the CNS to effectors such as muscles and glands
What are two defining features of motor neurons
Short dendrites and long axons
What are the sizes in which a neuron can vary
Less than a millimetre to up to a meter long
What does the cell body contain
What does that contain itself
Cell body contains a nucleus which contains the genetic material of the cell
What protrudes from the cell body
What do these carry impulses from and to
Dendrites
Carry impulses from the neighbouring neurons towards the cell body
Where does the axon carry impulses
Away from the cell body down the length of the neuron
What is the fatty layer that covers the axon called
What is its purpose (2)
The myelin sheath
Protects the axon and speeds up electrical transmission of the impulse
What would occur if the myelin sheath was continuous
What is in place to prevent this
There would be reverse effects and slow down electrical impulses
Nodes of ranvier - segmented gaps
How do the nodes of ranvier further speed up impulses
Speed up the transmission of impulses by forcing it to ‘jump’ across the gaps.
What is at the end of the axon
Terminal buttons
What is the gap between two neurons called
Synapse
Where are motor neurons found
Cell bodies
Axons
The cell bodies are in the CNS
But long axons form part of the PNS
Where are sensory neurons found
Outside the CNS in the PNS
What are the clusters of sensory neurons in the PNS called
Ganglia
What percentage of neurons are relay neurons
97%
Where are most relay neurons found
In the brain and the visual system
When a neurone is in resting state what is the charge like inside and outside the neuron
In resting state the inside of the cell is negatively charged compared to the outside
When a neuron is activated by a stimulus when is the charge like inside and outside the cell
The inside of the cell becomes positively charges for a split second
What is cause by the inside of a neuron being positive charged for a second
An action potential
If the action potential is reached what occurs with electrical impulses
They travel down the axon towards the end of the neuron
Neuron’s communicate with each other within groups know as what
Neural networks
Are signals between synapses transmitted electrically or chemically
Chemically
What is the scientific term for the end of the neuron
The presynaptic terminal
When the electrical impulse reaches the presynaptic terminal what occurs
Triggers what from where
Triggers the realise of neurotransmitters from synaptic vesicles
Define synaptic transmission
The process by which neighbouring neuron’s communicate with each other by sending chemical messages across the synapse that separates them
Define neurotransmitter
brain chemicals released from synaptic vesicles that relay signals across the synapse from one neuron to another.
Where are neurotransmitters released from
Synaptic vesicles
What two categories can neurotransmitters be divided into
Those that perform an excitatory function and those that perform an inhibitory function
When a neurotransmitter crosses the synapse what takes it up.
Where is this located
Taken up by a postsynaptic receptor site
Located on the dendrites of the next neuron
What occurs to the chemical message at the postsynaptic receptor site
The chemical message is converted back into an electrical impulse
Can transmission be multidirectional
Why
No - can only travel one way
Neurons have presynaptic terminals at one end and postsynaptic receptor sites at the other
What is unique about each neurotransmitter and receptor site
Each neurotransmitter has its own specific molecular structure that fits perfectly into a postsynaptic receptor site.
Do neurotransmitters have specialist functions
Give an example if necessary
Yes
Acetylcholine (ACh) found at each point a motor neuron meets a muscle, upon release it causes muscles to contract
Name the two effects a neurotransmitter can have on the neighbouring neuron
Excitatory or inhibitory
Define excitation
what does this mean about the likelihood of the impulse being passed on to
When a neurotransmitter increases the positive charge of the postsynaptic neurone.
Increases the likelihood that the postsynaptic neuron will pass on the electrical impulse
Define inhibition
What does this mean about the likelihood of the impulse being passed on
When a neurotransmitter increases the negative charge of the postsynaptic neuron.
Decreases the likelihood that the postsynaptic neuron will pass on the electrical impulse
Give an example of an excitation neurotransmitter
Adrenalin
Give an example of an inhibition neurotransmitter
Serotonin
What two things is adrenalin
A hormone and a neurotransmitter
Whether a postsynaptic neuron fires is decided by the process of ______
Summation
What occurs in summation
Example with inhibitory net effect
The excitatory and inhibitory influences are summed.
If the net effect on the postsynaptic neuron is inhibitory then the postsynaptic neuron is less likely to fire
How does neurotransmitters travel across the synapse
By diffusion
Who discovered that specific areas of the brain are associated with particular physical and psychological functions
Paul Broca and Karl Wernicke
When was it discovered that specific parts of the brain are associated with particular physical and psychological functions
19th century
What was generally supported before the investigations made by Broca and Wernicke on specific areas being associated with specific functions
Generally supported the holistic theory of the brain
That all parts of the brain were involved in the processing of thought and action
What did Broca and Wernicke argue for, for future research
Localisation of functions
Define localisation of function
The theory that different areas of the brain are responsible for specific behaviours, processes or activites
What does localisation of function suggest will occur if a certain area of the brain becomes damaged
The function associated with that area will also be affected
What is the ‘main part’ of the brain called
The cerebrum
Describe what the cerebrum is divided into
Two symmetrical halves called the left and right hemisphere
What is the term given to some of our physical and psychological functions being controlled or dominated by a particular hemisphere
Lateralisation.
What side of the body does the left hemisphere control as a general rule
Right-hand side of the body
What side of the body does the right hemisphere control as a general rule
The left-hand side of the body
Where is the cerebral cortex
The outer layer of both hemispheres
How many centres is the cerebral cortex of both hemispheres divided into
4
Name the 4 centres that the cerebral cortex of both hemispheres is subdivided into
The frontal lobe
The parietal lobe
The occipital lobe
The temporal lobe
What is a ‘lobe’
A part if an organ that is separate in some way from the rest of the
Define motor area
A region of the frontal lobe involved in regulating movement
Where is the motor area located
At the back of the frontal lobe in both hemispheres
What does the motor area control
Voluntary movement in the opposite side of the body
What would result from damage to the motor area
may result in a loss of control over fine movements
Define somatosensory area
An area of the parietal lobe that processes sensory information such as touch
Where is the somatosensory area located
At the front of both parietal lobes
What separates the motor and somatosensory areas
A ‘valley’ called the central sulcus
What does the somatosensory area do
Is where sensory information from the skin is represented.
What does the amount of somatosensory area devoted to a particular body part denote
Its sensitivity
How much of the somatosensory area is devoted to receptors for our face and hands
Over half
Define the visual area
A part of the occupational lobe that receives and processes visual information
Where is the visual area located
In the occupational lobe as the back of the brain
Where does each eye send information from and too
From the right visual field to the left visual cortex
From the left visual field to the right visual cortex
What would occur if there was damage to the left hemisphere in the visual area
Would produce blindness in par of the right visual field of both eyes
Define the auditory area
Located in the temporal lobe and concerned with the analysis of speech-based information
Where is the auditory area located
In the temporal lobe
What will damage to the auditory area cause
What will be the case with the more extensive damage
Hearing loss
The more extensive the damage the more extensive the hearing loss
What side of the brain is language restricted to
The left side
Who identified the area for speech production
Paul Broca (1880s)
What is the area for speech production in the brain called
Broca’s area
Define Broca’s area
An area of the frontal lobe in the left hemisphere, responsible for speech production
Where is the Broca’s area located
In the frontal lobe of the left hemisphere
What is the Broca’s area function
Speech production
What does damage to the Broca area cause
Damage causes Broca’s aphasia
Describe what Broca’s aphasia is like
(General effect - parts of words that are difficult)
Characterised by slow speech, laborious and lacking in fluency.
Difficulty with prepositions and conjunctions.
Who was Broca’s most famous patient?
Why were they called this?
‘Tan’
That was the only word he could say.
What area of the brain was identified by Karl Wernicke
Wernicke’s area
Define Wernicke’s area
An area of the temporal lobe in the left hemisphere, responsible for language comprehension.
Where is Wernicke’s area located
In the temporal lobe encircling the auditory cortex in the left hemisphere.
What is Wernicke’s area responsible for
Language comprehension.
No problem producing language but severe difficulty understanding it
What does damage to the Wernicke area cause
Wernicke’s aphasia
Describe the features of Wernicke’s aphasia
People with Wernicke’s aphasia will produce nonsense words as part of the content of their speech
What is the official name for ‘nonsense words’
Neologisms
What are the two strengths of localisation theory
Damage to areas of the brain has been linked to mental disorders
Evidence from brain scans that supports the idea that many everyday brain functions are localised
What is the last resort method for treating mental disorders
Neurosurgery
What does neurosurgery target
Specific areas of the brain which may be involved in the mental disorder
Give an example of a specific area of the brain being linked to a mental disorder
(OCD, what is this linkage called)
Cingulotomy involves isolating a region called the cingulate gyrus which has been implicated in OCD
Who completed research on OCD within damage to areas of the brain being linked to mental disorders
Darin Dougherty et al (2002)
Who was Dougherty’s subjects in his research on damage to areas of the brain being linked to OCD
44 people with OCD who had undergone a cingulotomy.
What was Dougherty’s findings when researching OCD and the impact of cingulotomy
(% successful and % partial)
After 32 weeks post-surgery about 30% had met the criteria for successful response to the surgery.
14% have a partial response.
What does the success of Cingulotomy on OCD suggest about behaviours associated with serious mental illnesses
Behaviours associated with serious mental disorders may be localised
Who completed research on the Broca’s and Wernicke’s area with brain scans
Steven Petersen et al (1988)
What did Petersen demonstrate using brain scans to research the Broca’s and Wernicke’s areas
Demonstrated how Wernicke’s area was active during a listening task
Broca’s area was active during a reading task
Who completed a review on long-term memory studies under brain scans supporting brain functions are localised
Buckner and Petersen(1996)
What did Buckner and Petersen reveal in their review of long-term memory studies under brain scans supporting brain functions being localised
Revealed that semantic and episodic memories reside in different parts of the prefrontal cortex.
What have objective methods for measuring brain activity provided (brain scans)
Sound scientific evidence that many brain functions are localised
Who’s research challenges the localisation theory
Karl Lashley (1950)
What was Lashleys method when making a counterpoint to brain scans supporting localised brain functions
He removed areas of the cortex (between 10-50%) in rates that were learning the route through a maze.
What was Lashley’s findings when challenging localisation theory
No area of the cortex was proven to be more important than any other area in terms of the rats’ ability to learn the route of the maze.
What did Lashley’s findings suggest about the location of learning and higher cognitive processes within the brain
Higher cognitive processes, such as learning, are not localised but distributed in a more holistic way in the brain.
What is one limitation for Broca’s area and Wernicke’s area
Language may not be localised to just these two areas
Who completed a recent review on language in Broca’s and Wernicke’s area
Anthony Dick and Pascale Tremblay (2016)
What did Dick and Tremblay find about modern researchers thoughts on the Broca’s and Wernicke’s area
Only 2% of modern researcher’s think that language in the brain is completely controlled by Broca’s and Wernicke’s area.
What have fMRI’s shown about languages location in the brain rather than just being located in the Broca’s and Wernicke’s areas
Language function is distributed far more holistically in the brain.
Language streams have been identifies across the cortex
Where have language streams now been shown to be within the brain
Identified across the cortex, including brain regions in the right hemisphere, as well as subcortical regions such as the thalamus.
How does new evidence on language location in the brain contradict localisation theory
Rather than being in a confined couple of key areas, language may be organised more holistically in the brain.
Who is the most famous case study of damage to the brain
Phineas Gage
What happened to Phineas Gage
Was working on a railroad.
Dropped his tampering iron onto the rock causing the explosive to ignite.
Explosion hurled the meter-length pole through his left cheek, passing behind his left eye, and exciting his skull from the top of his head.
What area of the brain was taken out by the pole in Phineas Gage
Mos of his left frontal lobe
What was the effect of the loss of the left frontal lobe in Phineas Gage
Changed from someone who was calm and reserved into a quick-tempered and rude person.
What did the change in Phineas gage suggest about the frontal lobe
The frontal lobe may be responsible for regulating mood
Draw and label the different areas of the brain
- check on google
Define hemispheric lateralisation
The idea that the two halves of the brain are functionally different and that certain mental processes and behaviours are mainly controlled by one hemisphere rather than the other.
Is language localised or lateralised
Both
Give an example of a function where the localised area appears in both hemispheres
The visual areas is in the left and right occipital lobe - located in the left hemisphere and right hemisphere respectively.
Where are the two main centres for language located
Can it therefore be referred to as lateralised
Two main centres are only in the left hemisphere for most people
Can say it is lateralised.
What can the right hemisphere only produce in terms of language
What does it also contribute to in language
Rudimentary words and phrases
Emotional context
What is the LH referred to in language
The analyser
What is the RH referred to in languages
The synthesiser
Name 3 areas of the brain that are not lateralised
Vision, motor and somatosensory areas appear in both hemispheres
What side of the body does the RH control in motor
What side of the body does the LH control in motor
Left
Right
What is the scientific term given to the RH controlling the left side of the body and the LH controlling the right side of the body in motor
Contralateral wiring
Can say the brain is cross-wired
What is the case in vision:
What is the left visual field in both eyes connected to
What is the right visual field in both eyes connected to
Left visual field in both eyes is connected to the right hemisphere
Right visual field in both eyes is connected to the left hemisphere
What two words can describe vision and the brain as a result of each visual field being controlled by the opposite hemisphere
Both contralateral and ipsilateral
What does vision being both contralateral and ipsilateral enable
The visual areas to compare the slight different perspective from each eye and aids depth perception.
What other feature has a similar arrangement to vision
Auditory input and auditory area
What does the auditory input and auditory area having a similar arrangement to vision enable
The disparity from the two inputs helps us locate the source of sound
What does a ‘split-brain’ operation involve
(Overall and mainly)
Severing the connections between the RH and LH
Mainly the corpus callosum
A split-brain operation is a surgical procedure used to reduce what
Epilepsy.
What happens in the brain during an epileptic seizure
The brain experience’s excessive electrical activity which travels from one hemisphere to the other.
What does split-brain research focus its studies on
Studies how the hemispheres function when they can’t communicate with each other
When did split-brain research begin
The 1960s
Define split-brain research
A series of studies involving people with epilepsy who had experienced a surgical separation of the hemispheres of their brain to reduce the severity of their epilepsy.
Enables researchers to test lateral functions of the brain in isolation
What does split-brain research allow researchers to test
Lateral functions of the brain in isolation
Who devised a system to study how two separated hemispheres deal with different functions
Roger Sperry (1968)
Who was Sperry’s subjects when studying how two separated hemispheres deal with functions
11 people who had a split-brain operation were studied.
What was Sperry’s procedure when investigating how two separated hemispheres deal with functions
A special set up was used in which an image could be projected to a participants right field of vision and the same or different image could be projected in the left field of vision.
How would connected hemispheres deal with two different images being shown in the RVF and LVF in Sperry’s experiment
The corpus callosum would share the information between hemispheres giving a complete picture of the visual world.
What would presenting the image to one hemisphere of a split-brain participant mean for the other in Sperry’s visual experiment
Information cannot be conveyed from that hemisphere to the other
What did Sperry find when an object was in the RVF in his visual experiment on split-brain subjects
When a picture of an object was shown to a participants RVF (linked to LH) the participants could describe what was seen.
What did Sperry find when an object was in the LVF in his visual experiment on split-brain subjects
Of the object was shown to the LVF (linked to RH) they said there was ‘nothing there’
Why could participants see objects in the RVF but not the LVF in Sperry’s visual experiment on split-brain
Messages from the RH cannot be relayed to the language centres in the LH.
Despite not being able to give verbal labels to objects projected in the LVF what two things could participants do in Sperry’s experiment on visual field and split-brain
They could select a matching objects out of sight using their left hand (linked to RH)
The left-hand was also able to select an object that was most closely associated with an object presented to the LVF.
What occurred in Sperry’s visual experiment on split-brain when a pinup picture was shown in the LVF
There was an emotional reaction but participants usually reported seeing nothing or just a flash of light.
What are the conclusions taken from Sperry’s experiment on vision in split-brain
(Overall and then specific functions of LH and RH)
Shows how certain functions are lateralised in the brain
Support the view that the LH is verbal and RH is ‘silent’ but emotional
What is one strength for hemispheric lateralisation
Research showing that even in connected brains the two hemispheres process information differently
Who used scans to identify which brain areas were active in visual processing tasks
Gereon Fink et al. (1996)
What was Fink’s method when trying to identify brain areas active during a visual processing task
Used PET scans and participant’s with connected brains
Participants were asked to attend to global elements of an image.
Participants were then asked to attend to finer details in the image
What did Fink discover about areas of the brain active when participants were asked to focus on the whole image and then focus on finer details
When participants were asked to attend to global elements of an image regions of the RH were much more active.
When asked to focus on the finer details the specific areas of the LH tended to dominate.
What was Fink’s conclusions when researching lateralisation in the connected brain
As far as visual processing is concerned, hemispheric lateralisation is a feature of the connected brain as well as the split brain
What is one limitation to the idea of hemispheric lateralisation
The idea that the LH as analyser and RH as synthesiser may be wrong
Who completed research into whether there is a ‘dominant’ side of the brain
Jared Nielsen et al (2013)
What was Neilsen’s method and subjects when researching whether there is a dominant side of the brain
Analysed brain scans from over 1000 subjects aged 7 to 29
What was Neilsen’s two findings when researching lateralisation and whether there is a dominant side of the brain
Found that people used certain hemispheres for certain tasks - evidence for lateralisation
There was no evidence of a dominant side - the notion of left- or right- brained people is wrong
What is one strength for Sperry’s split-brain research
There is more recent split-brain research
Who conducted more recent split-brain research
Michael Gazzaniga (Luck et al, 1989)
What did Gazzaniga show about split-brain participants compared to connected control participants on certain tasks
Split-brain participants actually performed better than connected control participants on certain tasks.
Give an example of a task in Gazzaniga’s research in which split-brain participants performed better than connected control participants
Split-brain participants were faster at identifying the odd one out in an array of similar objects.
Who provides an explanation for Gazzaniga’s findings on split-brain participants performing better on certain tasks
Kingstone et al (1995)
What is Kingstone’s explanation for why connected control participants performed worse then split-brain participants in Gazzaniga’s experiment
On the normal brain the LH’s better cognitive strategies are ‘watered down’ by the inferior RH
Which of Sperry’s findings does Gazzaniga and Kingstone’s research and explanation support
Supports Sperry’s findings that the ‘left brain’ and ‘right brain’ are distinct
What is one limitation of Sperry’s research
Causal relationships are hard to establish
What was the issue with Sperry’s control group in his split-brain research
(What type of major variable is this)
None of the participants in the control group had epilepsy.
Major confounding variable
What does a lack of epilepsy participants in the control group mean for Sperry’s findings and their cognitive abilities
Differences observed between the two groups may be the result of epilepsy rather than split brain.
Some of the unique features of the split-brain participant’s cognitive ability’s might have been due to their epilepsy.
What is the counterpoint to differences between the control and split-brain group could be done to epilepsy in Sperry’s research
Fink’s research supports Sperry’s conclusions
What 3 ethical measures were in place within Sperry’s split-brain research
Split-brain operations were not performed for the purpose of research - participants were not deliberately harmed.
All procedures were explained to the split-brain participants
Full informed consent was obtained
What were the two ethical implications in Sperry’s split-brain research
Trauma of the operation might mean that participants did not fully understand the later implications for what they had agreed to.
The participants were subject to repeated testing over a lengthy period of time (years in some cases) and this may have been stressful over time.
Define plasticity
Describes the brain’s tendency to change and adapt as a result of experience and new learning.
Generally involves the growth of new connections.
During infancy what does the brain experience a rapid growth of
The number of synaptic connections
Who stated the age the number stops increasing and peak number of synaptic connections
Gopnik et al (1999)
At what age does the increase of synaptic connections peak
At 2-3 years old
What is the peak number of synaptic connections per neuron
15,000 per neuron
Are their more or less synaptic connections at 2-3 yrs or in adult hood
By how much
Twice as many at 2-3 yrs than in adulthood
As we age what two things happen to synaptic connections
Rarely-used connections are deleted
Frequently-used connections are strengthened
What is the name given to the process of deleting and strengthening different synaptic connections
Synaptic pruning
Is the adult brain capable of change?
What enables it?
Yes
Synaptic pruning enables lifelong plasticity
What enables life long plasticity
Synaptic pruning
What occurs in synaptic pruning in adults
New neural connections are formed in response to new demands on the brain
Who conducted research into plasticity on taxi drivers
Eleanor Maguire et al (2000)
Who was Maguires subjects in research into plasticity
What did she compare them to
Studied the brains of london taxi drivers
Compared with a control group
What things did Maguire find structurally in the brains of london taxi drivers
Significantly more volume of grey matter in the posterior hippocampus than in a matched control group
What function does the grey matter in the posterior hippocampus have
(Maguire’s research on taxi drivers)
It is associated with the development of spatial and navigational skills in humans and other animals
What test is part of the london taxi driver training course
What does this include
Test called ‘the knowledge’
Assesses their recall of the city streets and possible routes.
What was the meaning behind Maguire’s findings on london taxi drivers in terms of plasticity
The learning experience alters the structure of the taxi drivers brains
What was the positive correlation in Maguire’s findings (taxi drivers)
The longer the taxi drivers had been in the job, the more pronounces was the structural difference.
Who conducted an experiment on synaptic pruning in medical students
Bogdan Draganski et al (2006)
What was Draganski’s method in studying plasticity
Imaged the brains of medical students three months before and after their final exams
What was Draganski’s findings on plasticity in medical students
Learning-induces changes were seen to have occurred in the posterior hippocampus and the parietal cortex.
Define functional recovery
A form of plasticity following brain damage through trauma.
The brains ability to redistribute or transfer functions usually performed by a damaged area to other Un damaged areas.
What type of plasticity is functional recovery an example of
Neural plasticity
Hat have neuroscientists suggest happens to the rate at which functional recovery occurs over time
The process can occur quickly after trauma and then slow down after several weeks or months.
What may an individual with brain damage need after functional recovery has slowed or stopped
Rehabilitative therapy to further their recovery
How is the brain able to retire and reorganise itself after damage
By forming new synaptic connections close to the area of damage
What are activated or unmasked to enable functioning to continue after brain damage
Secondary neural pathways
What do secondary neural pathways do in an undamaged brain
They would not typically be used to carry out certain functions
Who suggested that secondary neural pathways are activated to enable functioning to continue
Doidge (2007)
Name the three structural changes in the brain that supports the process of activating secondary neural pathways
Axonal sprouting
Denervation supersensitivity
Recruitment of homologous areas on the opposite side of the brain
Describe axonal sprouting
The growth of new never endings which connect with other undamaged never cells to form new neuronal pathways
Describe denervation supersensitivity
Occurs when axons of a similar function become aroused to a higher level to compensate for the ones that are lost.
What can the negative be of denervation supersensitivity
The negative consequence of oversensitivity to messages such as pain
Give an example of recruitment of homologous areas on the opposite side of the brain
If Broca’s area was damaged on the left-side of the brain, the right side equivalent would carry out its function.
What can happen to recruitment of homologous areas on the opposite side of the brain after a period of time
Functionality can shift back to its original side of the brain
What does recruitment of homologous areas on the opposite side of the brain allow for specific tasks
They can still be performed
What is one limitation of plasticity
It may have negative behavioural consequences
Who conducted evidence into the brain’s adpatation to prolonged drug use
Medina et al. (2007)
What did Medina’s research into the brains adaptation on prolonged drugs use show
Prolonged drug use leads to poorer cognitive function in later life, as well as increased risk of dementia.
Who investigated phantom limb syndrome
Ramachandran and Hirstein (1998)
What percentage of amputees have been known to develop phantom limb syndrome
60-80%
What is phantom limb syndrome
The continued experience of sensations in the missing limb as if it were still there.
What two words describe the sensations experienced in phantom limb syndrome
Unpleasant and painful
What did Ramachandran and Hirstein think causes phantom limb syndrome within the brain
Cortical recognition in the somatosensory cortex
What do the findings on prolonged drug use and the phantom limb syndrome suggest about the brains ability to adapt
The brains ability to adapt is not always beneficial
What is one strength of brain plasticity
It may be a life-long ability
In general what does plasticity reduce with
Age
Who conducted research on golfers and brain plasticity being a life-long ability
Ladina Bezzola et al. (2012)
What was Bezzola’s method for investigating brain plasticity in adults (golf)
Participants aged 40-60
40 hours of gold training for novice golfers
Compared fMRI scans between the golfers and a control group
What was Bezzola’s findings when investigating brain plasticity in adults (golfers)
What do they suggest
There was reduced motor cortex activity in the novice golfers compared to a control group.
Suggests more efficient neural representations after training and therefore neural plasticity can continue throughout lifespan.
What is one strength of functional recovery research
Real-world application
Understanding the processes involved in plasticity has contributed to what field
The field of neurorehabilitation
What therapy is used in stroke patients as an example of functional recoveries real-world application
(Name and describe)
Constraint-induced movement therapy.
Repeatedly practice using the affected part of their body.
Why is research into functional recovery useful to medical professionals
Allows them to know when interventions need to be made
What is one limitation of functional recovery
Level of education may influence recovery rates
Who researched education and brain recovery
Eric Schneider et al (2014)
What was Schneider’s general findings on education and brain recovery
what is education taken as an indicator of
The more time people with a brain injury had spent in education - taken as an indicator of their cognitive reserve - the greater their chances of a disability-free recovery
What were the two statistical findings of Schneider’s findings on education and brain recovery
40% of those who achieved a disabled free recovery had more than 16 years education.
10% of those who achieved a disabled free recovery had less than 12 years education.
What is implied for people with brain damage who have insufficient disabled free recovery
They are less likely to achieve full recovery
What are techniques for investigating the brain often used for in general
Medical purposes in the diagnosis of illness.
What is the purpose of scanning in psychology
Often to investigate localisation - determine which parts of the brain do what
Name the four techniques used for localisation in psychology that you study in detail
Functional magnetic resonance imaging
Electroencephalogram
Event-related potentials
Post-mortem examinations
Name the three scanning techniques that come up in psychology
Which two do you study in my detail
PET scans
Study in more detail:
fMRI
EEG
Define Functional magnetic resonance imaging (fMRI)
A method used to measure brain activity while a person is performing a task
Detects radio waves from changing magnetic fields.
What does fMRI enable researchers to detect
Which regions of the brain are rich in oxygen and thus are active
What two things does fMRI detect changes in
Blood oxygenation
Flow of blood
Outline the stages of haemodyamic response - oxygen
An area of the brain is more active and consumes more oxygen
Blood flow is directed to the active area to meet this demand.
What type of image does fMRI produce
What is the proper name
3D images
Activation maps
What will an fMRI show us when a certain task is performed
Which parts of the brain are involved in this particular mental process.
What type of waves does fMRI detect
Radio waves
Where do radio waves come from in fMRI
Changing magnetic fields
What is the main help received by fMRI
Helps understanding of localisation of function
Define electroencephalogram (EEG)
A record of the tiny electrical impulses produced by the brain’s activity.
By measuring characteristic wave patterns, the EEG can help diagnose certain conditions of the brain.
What does EEG measure
Characteristic wave patterns
What is the main help provided by EEG
Diagnosing certain conditions of the brain
What is fixed into an individuals scalp during EEG
How is this done
Electrodes
Using a skull cap
What do scan recordings represent from an EEG
What generates patterns
The brainwave patterns that are generated from the action of thoughts of neuron’s.
What type of patterns indicate neurological abnormalities in EEG
Unusual arrhythmic patterns
Name 3 neurological abnormalities that EEG can highlight in the brain
Epilepsy, tumours and some sleeping disorders
What is the issue with EEG in its raw form
It is crude and an overly general measure of brain activity
What is contained within EEG data that may be of interest to cognitive neuroscientists
Associated with what 3 events
All the neural responses associated with specific sensory, cognitive and motor events.
What type of statistical technique is used to filter our all extraneous brain activity from the original EEG
Statistical averaging technique
When extraneous brain activity is filtered from an EEG what is left to study
Only responses that relate to the presentation of a specific stimulus or performance of a specific task.
What is the name given to the desired brain activity waves the ones which are responses that relate to the presentation of a specific stimulus or performance of a specific task.
Event-related potentials (ERPs)
Define event-related potentials (ERPs)
The electrophysiological response of the brain to a specific sensory, cognitive or motor event can be isolated through statistical analysis of EEG data.
What are ERPs in simple terms
Types of brainwave that are triggers by particular events
How do you get ERPs
By conducting a statistical analysis of EEG data
Define post-mortem examination
The brain is analysed after death to determine whether certain observed behaviours during the person’s lifetime can be liked to structural abnormalities in the brain.
What is the most likely case for those who individuals who’s brains are subject to post-mortem examinations
(What might they have, what two things will have been expressed)
Likely to be those who have a rare disorder and have experienced unusual deficits in cognitive processes or behaviour during their life time.
Areas of damage within the brain are examined in post-mortem examinations to establish what
The likely cause of the affliction the person experienced.
What may scientists use to ascertain the extent of the difference in post-mortem examination
A comparison with a neurotypical brain
What is post-mortem examinations try to ultimately link together
Certain observed behaviours and structural abnormalities
What is the strength for fMRI focused on safety
Does not rely on radiation like PET scans.
If administered correctly it is virtually risk-free, non-invasive and straightforward.
What is the strength for fMRI focused on image production
Produces games that have a very high spatial resolution, depicting detail by the millimetre.
Provides a clear picture of how Brian activity is localised.
What are the two overall positives of fMRI
Safe and produces a clear picture.
What are the two overall limitations to fMRI
Expensive
Poor temporal resolution
What is the limitation of fMRI focusing on price
Expensive compared to other neuroimaging techniques
What is the limitation of fMRI focusing on resolution
Poor temporal resolution.
Around a 5-second time-lag behind the image on screen and the initial firing of the neuronal activity.
May not truly represent moment-to-moment brain activity
What two things has EEG been extremely useful in studying
The stages of sleep
The diagnosis of conditions such as epilepsy.
Hat is one strength of EEG focusing on resolution
Extremely high temporal resolution.
Can accurately detect brain activity at a resolution of a single millisecond
What is the one limitation of EEG
The generalised nature of the information received.
Not useful for pinpointing the exact source of neural activity.
what does EEG not allow researchers to distinguish between
Activities originating in different but adjacent locations
What two things are ERPs frequently used to measure
(2 examples for second thing measured)
Cognitive functions and deficits such as the maintenance of working memory.
What are the two overall strengths of ERPs
Makes EEG more specific
Excellent temporal resolution
What is the strength of ERPs focusing on specificity
Brings much more specificity to the measurements of neural processes than could ever be achieved with raw EEG data.
What is the strength of ERPs focusing on resolution
As they are derived from EGG measurements they have excellent temporal resolution, especially when compared to fMRI
What are the two general limitations of ERPs
Lack of standardisation
Extraneous material must be eliminated
What is the limitation of ERPs focusing on standardisation
What does this make difficult
There is a lack of standardisation in ERP methodology between different research studies.
Makes it difficult to confirm findings.
What is the limitation with ERPs focusing on collecting pure data
To establish our data in ERP studies, extraneous material must be completely eliminated.
Not always easy to achieve
When was post-mortem evidence vital
In providing a foundation for early understanding of key processes in the brain.
Prior to the development of scanning techniques
Who relied on post-mortem studies in establishing links between language, brain and behaviour
Paul Broca and Karl Wernicke
Who’s brain was study’s in post-mortem examination to try and associate areas of damage with memory deficits
HM
What are the 3 overall limitations with post-mortem studies
Causation
Observed damage linked to deficits
Informed consent
What is the limitation with post-mortem examinations focusing on links made
Observed brain damage may not be linked to the deficits under review but to some other unrelated trauma or decay.
What is the limitation with post-mortem examination focusing on informed consent
Ethical issues of consent from the individual before death
Participants may not be able to provide informed consent
Explain an example focusing on the limitations of informed consent within post-mortem examinations
HM who lost the ability to form memories was not able to provide informed consent.
Post-mortem research has been conducted on his brain anyways.
What type of organisms are subject to biological rhythms
All living organisms
Define biological rhythms
Distinct patterns of changes in the body activity that conform to cyclical time periods.
Influences by internal body clocks as well as external changes to the environment.
Give the biological name for the two things that govern biological rhythms
Endogenous pacemakers
Exogenous zeitgebers
Define endogenous pacemakers
The body’s internal biological clocks
Define exogenous zeitgebers
External changes in the environment
What is the scientific term given to rhythms occuring many times in the day
Ultradian rhythms
Give the scientific name for rhythms taking longer than a day to occur
Infradian rhythms
What is the scientific name given to rhythms that take longer than infradian rhythms
Circannual rhythms
What is the name given to rhythms that last for around 24 hours
Circadian rhythms
Define circadian rhythms
Biological rhythms, subject to a 24-hour cycle, which regulate a number of body processes.
Give the two examples of circadian rhythms studies in more detail
Sleep/wake cycle
Core body temperature
Name the most important exogenous zeitgeber in the sleep/wake cycle
Daylight
Is the sleep/wake cycle governed by endogenous pacemakers or exogenous zeitgebers
Governed by an endogenous pacemaker
What is the name given to the endogenous pacemaker in the sleep/wake cycle
Suprachiasmatic nucleus (SCN)
Where is the SCN located
Above the optic chiasm
What does the SCN provide information from and on
Provides information from the eye about ligth
What can the exogenous zeitgebers do to the SCN
The exogenous zeitgebers (in this case light) can reset the SCN
Which psychologists completed the cave-study
Michel siffre
What is Siffre’s method to study the effects on his own biological rhythms
Spent several periods underground.
Deprived of exposure to natural light and sound, but with access to adequate food and drink.
What occurred in Siffre’s study in the southern alps
Resurfaced in mid-September 1962 after two months in the caves.
He believed it to be mid-august
Where and for how long did Siffre experiment for after the Southern alps
In a Texan cave for 6 months
In what two places did Siffre experiment his own biological rhythms
Southern alps
Texan cave
What was Siffre’s findings on his own biological rhythms in the caves
(General biological rhythms and sleep schedule)
His free-running biological rhythm settled down to one that was just beyond the usually 24 hrs (around 25 hrs).
He did continue to fall asleep and wake up on a regular schedule.
Who conducted research similar to Siffre’s but in a WW2 bunker
Jurgen Aschoff and Rutger Wever (1976)
What was Aschoff and Wever’s method when studying sleep/wake cycles
Placed a group of participants in a world war 2 bunker that was deprived of natural light for 4 weeks.
What was Aschoff and Wever’s findings on the sleep/wake cycle in their WW2 bunker experiment
(Overall finding - what did the anomalies show)
All but one participant displayed a circadian rhythm between 24 and 25 hours.
The one participant’s sleep/wake cycle extended to 29 hours.
What did the bunker and Siffre’s experiment suggest about the length of the natural sleep/wake cycle time
It may be slightly longer that 24hrs
What did the bunker and Siffre’s experiment suggest about the effects of exogenous zeitgebers on the natural sleep/wake cycle
(Explain and Give an example of 24hr exogenous zeitgebers)
The natural sleep/wake cycle is entranced by exogenous zeitgebers associated with out 24hr day - such as the number of daylight hours, typical meal times)
Who completed a study showing that we should not underestimate the influence of exogenous zeitgebers on our internal biological clock
Simon Folkard et al (1985)
What was Folkard’s method when studying the influence of exogenous zeitgebers on our internal body clocks
(How many people, where, how long, what did they have to do, what changed, by how much)
12 people agreed to live in a dark cave for three weeks.
Had to go to bed when the clock said 11:45pm and wake up at 7:45am
Over the course of the study the researchers gradually speeded up the clock without participant knowledge.
Th 24hr day eventually lasted only 22 hrs
What was Folkard’s findings in his changing of time in the day experiment?
Only one of the participants was able to comfortably adjust to the new regime
What does Folkard’s findings in his changing of hours in the day experiement suggest about the effect of exogenous zeitgebers on circadian rhythms
Existence of a strong free-running circadian rhythm that cannot be easily overridden by exogenous zeitgebers
What are the two strengths of research into circadian rhythms
(State scientific term for one)
It provides an understanding of the adverse consequences that occur when they are disrupted (desynchronisation)
It has been used to improve medical treatments.
Research has shown that at what time do night workers engaged in shift work experience a period of reduced concentration
What is this called
6 in the morning
A circadian trough
What is more likely to happen within a circadian trough at work
Mistakes and accidents
Who found out that the circadian trough is most likely to occur at 6am
Boivin et al. 1996
Who studied the relationship between shift work and poor health
Knutsson (2003)
What did Knutsson find about shift workers and poor health
Shift workers are 3x more likely to develop heart disease than people who work a more typical work pattern.
What do Boivin and Knutsson’s research show about research into the sleep/wake cycle entering the real-world
It may have real-world economic implications in terms of how best to manage worker productivity and health
What is the counterpoint to studying circadian rhythms in shift work
Studies investigating the effects of shift work ten to use correlational methods.
What does the use of correlational methods when investigating shift work mean for the results on desynchronisation
It is difficult to establish whether desynchronisation of the sleep/wake cycle is actually a cause of negative effects.
Who conduced research on other factors that lead to negative impacts for night shift workers
Charlene Solomon (1993)
What did Solomon conclude about other factors of negative impacts for night shift workers
High divorce rates in shift workers might be due to the strain of deprived sleep and other influences such a s missing out on important family events.
What does Solomon’s research suggest about biological factors and shift work
It may not be biological factors that create the adverse consequences associated with shift work
Name 3 basic body processes that circadian rhythms co-ordinate
Heart rate, digestion and hormone levels
How do heart rate, digestion and hormone levels change throughout the day
They rise and fall
What field has the rise and fall of circadian rhythms throughout the day led to
Chronotherapeutics
What is chronotherapeutics
How medicinal treatment can be administered in a way that corresponds to a person’s biological rhythms.
Give an example of a medicine needing to be taken at a specific time of the day due to a circadian rhythm - chronotherapeutics
Aspirin is most effective as a treatment for heart attacks if taken last thing at night.
Explain why aspirin is most effective when taken late at night in terms of its corresponding circadian rhythm
Heart attacks are most likely to occur in the early morning
How does aspirin reduce the chances of a heart attack - chronotherapeutics
Aspirin reduces blood platelet activity reducing the risk of blood clots in the coronary arteries and therefore heart attack risk.
Who’s research supports the fact that aspirin should be taken last thing at night to since with platelet activity rhythm
Bonten et al (2015)
What is one limitation of research into circadian rhythms
Generalisations are difficult to make
Why were generalisations difficult to make from Aschoff & Wever and Siffre’s studies
What is the issue with this
They are based on very small samples of participants.
Sleep/wake cycles may vary widely from person to person
Who researched the variety in difference of sleep/wake cycles from person to person
Charles Czeisler et al. (1999)
What did Czeisler find about the variation in sleep/wake cycles from person to person
Individual differences in sleep/wake cycles vary from 13 to 65 hours.
Who completed research on natural preferences for sleep/wake cycles
Jeanne Duffy et al (2001)
What did Duffy reveal about natural preferences in sleep/wake cycles
(What were these 2 types called)
Some people have a natural preference for going to bed early and rising early - Larks
Others prefer the opposite - owls
What did Siffre observe in a later study of his own sleep/wake cycle (1999)
His own sleep/wake cycle had slowed down since he was young.
What does Czeisler, Duffy and ever Siffre’s later research suggest about generalisations in sleep/wake cycles
It is difficult to use research data to discuss anything more than averages, which may be meaningless.
What term is used to describe the biological clock when there is no influence by exogenous zeitgebers
Free-running
Define infradian rhythm
A type of biological rhythm with a frequency of less than one cycle in 24 hours.
Name the two examples of an infradian rhythm studied in greater detail
The menstrual cycle
Seasonal affective disorder
What is the menstrual cycle governed by
Why is this infradian
Governed by monthly changes in hormone levels which regulate ovulation
Less than one cycle in 24 hours
The menstrual cycle refers to the time between what and what
Time between the first day of a woman’s period - when the womb lining is shed - to the day before her next period.
How long does the menstrual cycle take on average
What is the range of length that is considered normal
28 days
24-35 days
During the cycle what hormone rises in levels
Oestrogen
What does oestrogen cause in the menstrual cycle
Causes the ovary to develop an egg and release it
What is the production and releasing of an egg called in the menstrual cycle
Ovulation
What hormone is produced after ovulation in the menstrual cycle
Progesterone
What does progesterone do in the menstrual cycle
Helps the womb lining to grow thicker, reading it for pregnancy
What occurs to the egg and lining if pregnancy does not occur in the menstrual cycle
The egg is absorbed into the body, the womb lining comes away and leaves the body in menstrual flow.
Is the menstrual cycle a exogenous or endogenous system
Endogenous
Evidence suggests that the menstrual cycle may be effected by what type of factors
Give an example of one
Exogenous
The cycles of other women
Who conducted a study into how menstrual cycles may synchronise
Kathleen Stern and Martha McClintock (1998)
Who was stern and mcclintock’s participants when studying how menstrual cycles may synchronise
Studied 29 women with a history of irregular periods.
What were the samples of, from how many women and when were they gathered in Stern and McClintock’s study on how menstrual cycles may synchronise
Samples of pheromones were gathered from 9 of the women at different stages of their menstrual cycle.
How were pheromone samples collected in stern and mcclintock’s study of menstrual cycle synchronisation
Cotton pads placed in armpits for at least 8 hours.
What happened to the cotton pads that picked up pheromones in stern and mcclintock’s experiment on menstrual cycle synchronisation
(How were they treated, how were the pheromones transferred)
Pads were treated with alcohol and frozen
Pads were rubbed on the upper lip of the other participants
What pads were used on day one and two in Stern and Mcclintock’s study of synchronisation of the menstrual cycle
On day one, pads from the start of the menstrual cycle were applied to all 20 women
On day two pad from the second day of the menstrual cycle and so on
What was Stern and Mcclintock’s findings on the synchronisation of menstrual cycles through pheromones
68% of woman experienced changes to their cycle which brought them closer to the cycle of their pheromone donor.
What is the name given to a the mental depressive disorder which has a seasonal pattern of onset
Seasonal affective disorder (SAD)
Where is SAD described and diagnosed as a mental disorder
DSM-5
What are the main symtoms of SAD (3)
Low mood
General lack of activity
Lack of interest in life
What is SAD often referred to
Winter blues
When is SAD triggered
During the winter months when the number of daylight hours become shorter
What is the name given to the particular type of infradian rhythm that SAD is
Why does it fit into this other category
Circannual rhythm
It is subject to a yearly cycle
What other rhythm can SAD be classed as and why
Circadian rhythm
SAD may be due to the disruption of the sleep/wake cycle and this can be attributed to prolonged periods of daily darkness during the winter.
What hormone have psychologists hypothesised to be impacted in the cause of SAD
Melatonin
What happens to the hormone melatonin during the night
The pineal gland secretes melatonin until dawn when there is an increase in light
What impact does the winter months have on the secretion of melatonin
Lack of light in the morning means the secretion of melatonin continues for longer.
What is the link between longer secretion of melatonin and depression
(What other hormone is at play)
Longer secretion of melatonin is thought to have a knock-on effect on the production of serotonin.
Serotonin is liked to the onset of depressive symptoms
What is one of the most intensively researched ultradian rhythms
The stages of sleep or the sleep cycle
How many stages of the sleep cycle are there
5
How long does one sleep cycle last
Approximately 90 mins
Why is the sleep cycle an ultradian rhythm
It repeats throughout the course of the night so occurs more than once in 24 hours
What is each stage categories by?
What can this be monitored by?
Categorised by a different level of brainwave activity
EEG
What is sleep like in stages 1 and 2 of the sleep cycle
Light sleep where a person might be easily woken
What are the type of brain waves and what are they like in stage 1 of the sleep cycle
Alpha waves
High frequency and have a short amplitude
What type of waves and what are the waves like in stage 2 of the sleep cycle
Alpha waves
They continue from stage 1 but there are occasional random changes in the pattern
What are the occasional random changes in pattern called in stage 2 of the sleep cycle
Sleep spindles.
What is sleep like in stages 3 and 4 of the sleep cycle
Deep sleep or slow wave sleep (SW)
Difficult to wake someone up
What are the type of waves and what are they like in both stages 3 and 4 of the sleep cycle
Delta waves
Lower frequency and higher amplitude
What does someone experience in stage 5 of the sleep cycle
What is this sleep called
REM sleep
The body is paralysed but brain activity is close to that of an awake brain.
Eyes occasionally move around - Rapid Eye Movement (REM)
What is the type of wave produced in stage 5 / REM of the sleep cycle
Theta waves
In what stage of the sleep cycle are dreams most often experienced
At what stages might they also occur
REM - stage 5
Might be in the deep sleep of stage 3 and 4
What is one strength of menstrual synchrony research
It may be explained by natural selection
Who might synchronised menstrual cycles have had evolutionary salute for
Distant ancestors
Why might it have been advantageous for our distant ancestors to have had synchronised menstrual cycles in terms of survival
Advantageous to be fertile and become pregnant at the same time.
In a social group this would allow babies who lost their mothers to have breast milk, improving chances of survival.
What does an evolutionary basis suggest about synchronised menstrual cycles
It is an adaptive strategy
What is one limitation to the studies that focus on menstrual synchronisation
Their methodological shortcomings
What are three other factors that could effect change to the menstrual cycle other than pheromones
Stress, changes in diet and exercise
What might factors other than pheromones act as in an investigation on menstrual synchronisation
Confounding variables
Name another study on menstrual synchronisation that has failed to replicate the findings of Stern and McClintock
Trevathan et al (1993)
What is one strength of research into ultradian rhythms
It has improved understanding of age-related changes in sleep
What reduction have sleep scientists observed with age in sleep cycles
Slow wave sleep.
What hormone is mostly produces during SWS
What does this mean for older people
The growth hormone
SWS is reduced in older people
Who stated that resulting sleep deficits in older people may results in issues of old age
Eve Van Cauter et al (2000)
What is one issue in old age that could be a result of sleep deficit
Reduced alertness
What may be used to increase SWS in older people or people with sleeping disorders
Medication to increase relaxation
What does the findings on the reduction of SWS in older people suggest for the practicality of understanding ultradian rhythms
The knowledge of ultradian rhythms has a practical use
What is one limitation of ultradian rhythms research
There is significant variation between people
Who researched the differences in duration of each stage in the sleep cycle
Adrienne Tucker et al. (2007)
What was Tuckers findings on variation in duration of each stage of the sleep cycle
Found large differences between participants in terms of the duration of each sleep stage.
Particularly stages 3 and 4.
What does Tucker suggest determines the differences in duration of sleep stages
Likely to be biologically determined.
What does large differences in duration of stages in the sleep cycle for different people mean when trying to describe sleep.
It is difficult to describe ‘normal sleep’ in any meaningful way.
What is the most effective treatment for seasonal affective disorder
Light therapy
How is light therapy done for SAD
How does light therapy work
A box which stimulates very strong light to rest the body’s internal clock.
Who researched the effectiveness of light therapy on SAD
Sanassi (2014)
What was the statistic Sanassi found about how effective light therapy is for SAD
Reduced effects of SAD in 80% of people
Why is light therapy preferred for SAD over drug therapy
It is regarded as safe.
What is one of the benefits of conducting studies of sleep in a lab setting
It controls extraneous variables
What temporary variables can a researcher include when conducting sleep studies
Noise or temperature.
What is the negative of conducting studies in a sleep lab setting
Participants are attached to complicated machinery, leading participants to sleep in a way that does not represent their ordinary sleep patterns.
What makes us the suprachiasmatic nucleus and where is it located
A tiny bundle of nerve cells
Located in the hypothalamus in each hemisphere of the brain
Is the SCN a primary endogenous pacemaker or exogenous reitgeber
Endogenous pacemaker
What rhythm is the SCN influential in maintaining
Give an example of this type of rhythm
Circadian rhythms
Sleep/wake cycle.
What is the optic chiasm
Nerve fibres connected to the eye cross in an area called the optic chiasm
Nerve fibres crossing in the optic chiasm are coming from and to where
From the eye to the left and right visual area of the cerebral cortex
Where does the SCN lie in comparison to the optic chiasm
Just above
Where does the SCN receive information about light from
The optic chiasm
Can we detect light when eyes are closed?
What does this allow the biological clock to do?
Yes
Adjunct to changing patterns of daylight whilst we are asleep
Who studies the sleep/wake cycle in chipmunks with destroyed SNC connections in the brain
Patricia DeCoursey et al (2000)
What was DeCoursey’s method when investigating the SNC
Destroyed the SNC connections in the brains of 30 chipmunks who were then returned to their natural habitat and observed for 80 days
What were the two findings of DeCoursey’s study on chipmunks
The sleep/wake cycle of the chipmunks disappeared
By the end of the study a significant proportion of them had been killed by predators
Explain why in DeCoursey’s study a significant proportion of the chipmunks has been killed by predators
Presumably because they were awake, active and vulnerable to attack when they should have been asleep
Who bred mutant hamsters to study SNC
Martin Ralph et al. (1990)
What was Ralph’s method when investigating SNC
Bred ‘mutant’ hamsters with a 20-hour sleep/wake cycle.
Transferred SCN cells from the foetal tissue of mutant hamsters into the brains of normal hamsters.
What did Ralph find in his experiment on the SNC with mutant hamsters
The cycles of the normal hamsters with implanted SNC foetal tissue of mutant hamsters defaulted to 20 hours.
Where does the SCN pass information on day length and light it receives to
Pineal gland
What two pieces of information does the SNC pass to the pineal gland
Day length and light that it receives
Where is the pineal gland located
Just behind the hypothalamus
What type of mechanism is the reaction between the SNC and pineal gland
What cycle does it play a role in
Endogenous mechanism
Sleep/wake cycle
What hormone does the pineal gland produce and when
During the night - increased melatonin production
What does melatonin induce
When is it inhibited
Induces sleep and is inhibited during periods of wakefulness
Define endogenous pacemakers
Internal body clocks that regulate many of our biological rhythms.
Define exogenous zeitgebers
External factors that affect or entrain our biological rhythms.
Define sleep/wake cycle
A daily cycle of biological activity based on a 24-hour period (circadian rhythm) that is influenced by regular variations in the environment.
What is the process called when exogenous zeitgebers reset our biological clocks
Entrainment
What happens to the biological clock that controls sleep/wake cycles in the absence of external cues
It is free-running and continues to ‘tick’ in a cyclical pattern
What happens when environmental cues are reintroduced to the free-running cycle
The free-running cycle is ‘brought back into line’ by environmental cues.
What does exogenous light do to the main endogenous pacemaker (SCN)
It can reset it
What two things does light also have an indirect influence on
Key processes in the body that controls hormone secretion and blood circulation
Who researched whether light can be detected on skin receptor sights
Scott Campbell and Patricia Murphy (1998)
What was Campbell and Murphy’s method when investigating whether light can be detected by skin receptor sights
15 participants were woken at various times and a light pad was shone on the back of their knees
What was observed in Campbell and Murphy’s research on whether skin receptor sites can detect light
There was a deviation in the participants usual sleep/wake cycle of up to three hours in some cases.
What did Campbell and Murphy’s findings demonstrate about lights impacts on sleep/wake cycles
Light may be detected by skin receptor sites on the body
Light is a powerful exogenous zeitgeber that doesn’t need to rely on the eyes to exert its influence on the brain.
What is the sleep/wake cycle like in newborn babies
Pretty much random
At what age does the circadian rhythms begin
6 weeks
At what age are rhythms entrained by the schedules imposed by parents
By about 16 weeks of age
Give two examples of entrained schedules imposed by parents
Adult-determined mealtimes and bedtimes
What are the two most effective way of entraining circadian rhythms and beating jet lag
Adapting to local times for eating and sleeping
What are the two exogenous zeitgebers in the sleep/wake cycle studied in detail
Light and social cues
What are the two endogenous mechanisms studied in detail for the sleep/wake cycle
SCN and light
Pineal gland and melatonin
What is one limitation of SCN research
It may obscure other body clocks.
What 3 other organs can peripheral oscillators be found in
Lungs, pancreas and skin
What are the lungs, pancreas and skin also influenced by
What else do they do
The actions of the SCN
Act independently
Who researched changes in the circadian rhythms in liver cells
Francesca Damiola et al (2000)
What two things did Damiloa find in mice with feeding patterns, SCN and circadian rhythms in liver cells
Feeding patterns in mice could alter the circadian rhythm of cells in the liver by up to 12 hrs.
The rhythm of the SCB is unaffected
What is one limitation for the study of endogenous pacemakers
They cannot be studied in isolation
Why are animal studies for SCN justified
Very similar mechanisms at work across species.
If the SCN and pineal gland are present generalisations can be made about the human brain.
Are there ethical issues in animal studies on SCN
Yes loads
What are the limitations for exogenous zeitgeber’s
They do not have the same effect in all environments.
There is evidence that challenges their role
How long do people who live within the arctic circle experience almost total darkness for
6 months
What effect does 6 months of darkness have on the sleep/wake cycle for people in the arctic circle
They have similar sleep patters all-year round.
What do people living in the arctic circle suggest about endogenous pacemakers
They can override environmental changes in light
Who provides research that challenges the role of exogenous zeitgeber’s
Laughton Miles et al (1977)
Who did Miles study / what was the method when challenging the role of exogenous zeitgebers
Recounted the study of a young man, blind from birth, who has an abnormal circadian rhythm of 24.9 hours
He was introduced to social cues like regular meal times.
What was the findings when Miles recounted the study of the blind from birth man
Despite exposure to social cues, such as regular mealtimes, his sleep/wake cycle could not be adjusted.
What did Miles findings on the blind man tell us about social cues
Social cues alone are not effective in resetting the biological rhythm
Who’s studies suggested that exogenous factors may be more responsible for the changes in sleep patters amongst old people
Bernadette Hood et al (2004)
What did Hood find when investigating exogenous reitgeber effects on sleep/wake cycles in old people
Management of insomnia was improved if elderly people were generally more active and had more exposure to natural light.
