Biopsychology Flashcards
What is the cell body
Includes a nucleus which contains genetic material
What are dendrites
Branch like structures that come out of the nerve cell to connect with other neurons, they carry nerve impulses from other neurons towards the cell body
What is the axon
Carries nerve impulses away from the cell body, the length of axons varies from a few millimetres to over a meter in the spinal chord
What is the myelin sheath
What type of cells make up this
Insulated and protects the axon and helps speed up the electrical transmission along the axon
Schwann cells make the myelin
What is the node of ranvier
Are the gaps in the myelin sheath that forces the impulses to jump accords the gaps along the axon
Increases speed of the electrical impulse
What is the terminal button
At the end of the axon are the terminal buttons that send impulses to the next neurons across the synapse
Contain tiny sacs containing chemicals called neurotransmitters
What is the structure and function of a sensory neuron
They have long dendrites and short axons
Carry messages from the PNS to the CNS
Describe the structure and function of relay neurons
They have short dendrites and short axons
Connect the sensory neurons to the motor or other relay neurons
Describe the structure and function of motor neurons
They have short dendrites and long axons
Relay information from the cns to effectors such as muscles and glands
Name two types of effectors
Muscles
Glands
Define synaptic transmission
The process by which neighbouring neurons communicate with each other by sending chemical messages across the synapse
Describe what happens when the impulse travels down the axon and arrives at the ore synaptic terminal
1) Vesicles are release neurotransmitters into the synaptic cleft
2) receptors recieve the neurotransmitters in the post synaptic receptor site
3) the enzymes break down neurotransmitters if they don’t get to the receptors
4) the left over neurotransmitters are reabsorbed by vesicles in the pre synaptic membrane
5) neurotransmitters replenish
6) summation: the overall influence is summed, either: excitatory, inhibitory
What happens if the result of summation is excitatory
The neuron is more likely to fire and pass on the impulse
What happens if the overall influence is inhibitory
The neuron is less likely to fire
What does the central nervous system consist of
What is it’s function
The brain and spinal cord
It receives info from the senses and controls the body’s response
What is the function of the peripheral nervous system
To send information to the CNS from the outside world and transmit messages from the CNS to muscles and glands
What is the role of the somatic nervous system
Controls muscle movement and recieves information from sensory receptors to the CNS
What is the role of the autonomic nervous system
Controls vital functions in the body - transmits info to and from bodily organs
INVOLUNTARY
Name the two divisions of the ANS
Sympathetic nervous system
Parasympathetic nervous system
Both work in opposition to one another
What is the job of the glands
An organ in the body that produced substances such as hormones
Name 3 glands
The thyroid gland - thyroxine
Pituitary gland-master gland
Adrenal gland-adrenaline
Explain what happens during sudden stress
The ANS changes from parasympathetic state to a sympathetic state which prepares the body for fight or flight - sends a signal to the adrenal medulla/ releases adrenaline
Adrenaline causes increased heart pumping breathing more rapid releases blood sugar
Parasympathetic branch dampens down stress response returning to to normal
What does adrenaline cause
Rapid breathing
Inhibited digestion
Increase blood sugar- more energy
Heart beats faster- o2 to muscles
What does HPA axis stand for
What is it
Hypothalamus-pituitary-adrenal system
Sequence of bodily activity in response to stress
Explain what’s happens in response to prolonged stress
Hypothalamus releases CRH
CRH causes pituitary gland to release ACTH
ACTH stimulates the adrenal vortex to release cortisol
Cortisol fights inflammation and releases energy
Define localisation of function
The idea that specific parts of the brain have a specific function
Before the 19th century and Brocas and Wernickes work- what theory was accepted in relation to localisation do function
Holistic theory
What’s another word for localisation if function
Cortical specialisation
What is hemispheric lateralisation
One hemisphere has a different function to the other hemisphere
What is the function of the:
motor area
Somatosensory area
Visual area
Auditory area
1) movement
2) detects sensory events(pressure/touch/pain/temp)
3) processes light in retina
4) controls hearing (sound waves converted to nerve impulses)
What’s another word for a language abnormality
Aphasia
What is the function of
wernickes
Brocas
Wernickes/ speech comprehension
Brocas/ speech production
Explain Brocas work
Studied a patient- tan- with issues producing language-post morten…
He also studied 8 other patients with language deficits and lesions in the left hemisphere
SUPPORTS LOCALISATION
Explain Wernickes work
Discovered an area of the brain involved in understanding language in the left fontal hemisphere
Explain tulving work- what does this support
Tulving= radioactive gold/semantic & episodic memory/ monitored blood flow to DIFFERENT AREAS
Localisation of function
Explain Phineas Gage case study
What does this support
Phineas Gage= left frontal lobe removed/
Experienced mood problems/ left frontal lobe regulates mood/limited= non generalisable
Localisation of function
Explain Lashley work (animals)
What does this criticise
Removed part of cortex in rats that were learning a maze, found no area of the cortex was more or less important than any other part of the cortex when learning a maze
Criticises Localisation of function
(Pro holism)
Based on ANIMALS> not relatable
Explain Brain plasticity
What does this reject
When the brain becomes damaged- the brain can reorganise itself in an attempt to recover lost function
Shows that if one area was damaged the whole function SHOULD be inhibited= not the case
Rejects localisation of function- supports holism
Define brain plasticity
The brains ability to change and adapt because of experience- research has demonstrated that the brain continues to create neural pathways
What is the corpus callosum
Connects the two hemispheres together by a bundle of nerve fibres- allows communication within the hemispheres
Describe sperry’s research
Used split brain patients
Flashed a word into the right field of view- answer matches word
Flashed word into Left field of view, cannot say what they saw but can draw it
Describe sperry’s research
Used split brain patients
Flashed a word into the right field of view- answer matches word
Flashed word into Left field of view, cannot say what they saw but can draw it
Explain gazzanigas work
One patients developed the ability to speak out of the right hemisphere of the brain
Suggests language is too complex to be localised
Supporting holism
What is a advantage of sperrys work
Laboratory experiment
- high control
- replicatable
Name a disadvantage of sperrys work
Population validity
- not generalisable
- unique sample
Define brain plasticity
Refers to the brains ability to change and adapt due to experience
Define functional recovery
Refers to the transfer of functions from a damaged area of the brain after trauma to an undamaged area
What happens in the brain during recovery
The brain is able to reorganise itself by forming new synaptic connections
Name the four examples of brain plasticity
And summarise each one
Synaptic pruning- the process by which extra synaptic connections are eliminated
Axon sprouting- undamaged axons grow new nerve ending to reconnect neurons
Neuronal unmasking- dormant synapses open connections
Recruitment of homologous- similar areas
Explain Maguires work
What does this support
Used structural MRIs to investigate Hippocampal volume of taxi drivers
Found taxi drivers have a larger posterior hippocampal volume
Supports brain plasticity as it shows brains ability to change and adapt over time spent as a taxi driver
Explain Kuhn work
What does this support
Compared control group with one that spent time playing mario for two months at 30 mins a day
More grey matter in various brain areas
New synaptic connections
Supports brain plasticity shows how brain has adapted in response to the study
Explain kemperman work
What does this support
Investigated whether an enriched environment could alter the number of neurons in the brain
-more new neuron in brain of enriched caged rats
Supports brain plasticity - brain adapted
ANIMALS not generalisable to human
Explain Bezzola work
What did this support
Golfer- training for 40 hours, reduced motor cortex activity in novice golfers after 40 hours of practice
Brain plasticity- forms new connections
Define post mortems
Researchers study the physical brain of a person who displayed a particular behaviour while they were alive
Name and explain someone who used post mortems
Brocas- Tan
Examine his language ability when alive, then found he had a lesion in the area of the brain responsible for speech production in the post mortems
What’s a strength and a disadvantage of post mortems
✅allow for a more detailed examination of anatomical and neurosurgical aspects of the brain
🚨issue of causation- the death may not be linked to deficits in the brain
What is FMRI scans
Measures blood flow in the brain when a person performs a task
How does fmri scans study the brain
Uses neurons in the brain that are most active and use most energy- this requires glucose and oxygen, the neurons use the oxygen forming deoxygenated haemoglobin
Deoxygenated haemoglovin has a doffering magnetic quality to oxygenated haemoglobin
FMRI can detect the different magnetic qualities to create a dynamic 3D image of the brain
What is temporal resolution
How quickly the scanner can detect changes in brain activity.
Define spatial resolution
The smallest feature that the scanner can detect- allowing scientists to discriminate between different brain regions
Name an advantage and disadvantage of FMRI scans
Poor temporal resolution
Good spatial resolution
Describe sperry’s research
Used split brain patients
Flashed a word into the right field of view- answer matches word
Flashed word into Left field of view, cannot say what they saw but can draw it
Describe EEG scanners
Measure electrical activity through electrodes attached to the scalp
Small charges are detected by the electrodes in and are graphed over a period of time indicating the level of activity
Name the four types of EEG patterns
Alpha beta theta and Delta
Give an advantage and disadvantage of EEG scans
Good temporal resolution
Poor special recognition
Cannot provide information on what’s happening in the deepest parts of the brain
Can observe the brain in real time rather than the passive
What does ERP stand for
Event related potentials
Which of the method of scanning is similar to the ERP scans
EEGs
How are ERPs triggered
By specific events or stimuli
How are ERPs used
Electrodes on scalp to detect these very small voltage changes
Advantage and disadvantage of ERPs
Good temporal resolution
Poor special recognition
Cannot provide information on what’s happening in the deepest parts of the brain
Can observe the brain in real time rather than the passive
Define biological rhythms
Distinct patterns of changes in body activity that conform to a cyclical time period
Name three types of biological rhythm
Ultradian Rhythm
Circadian rhythm
Infradian rhythm
Define endogenous pacemakers
Internal body clock is that regulate many of our biological rhythms
What is the most important pacemaker in human beings
Where is it
Suprachiasmatic nucleus (SCN) In the hypothalamus
What does the SCN do
Controls sleep/wake cycle by detecting light through the optic nerve
Also regulated the production and secretion of melatonin which induces sleep
Define exogenous zeitgebers
External ques that affect our biological rhythms
What is the process used to reset our biological clock called
Entraining
Name three exogenous zeitgebers
Light
Food
Temp
DeFind circadian rhythm
A type of biological rhythm subject to a 24 hour cycle which regulates a number of body processes E.G.sleep wake cycle
Explain deCoursey work
What does this support
Destroyed the SCN connections in the brains of 30 chipmunks and returned them to their natural habitat
the sleep wake cycle disappeared
Supports the role of endogenous pacemaker in the sleep wake cycle because the rhythm disappeared
LIMITED=animals
Explain Siffres work
What dies this support
Spent several periods of time underground to study the effect on his biological rhythms
Deprived of natural light and sound
He continued to fall asleep and wake on a regular schedule
Supports the role of endogenous pacemakers- body continued a cycle
One person/ NON GENERALISABLE
Explain the work of Czeisler
What does this challenge
Most studies were not isolated from artificial light
Czeisler altered participants circadian rhythm down to 22 hours and up to 28 hours by using dim artificial lighting
Challenges previosu understanding of sleep wake cycle> failed to take into account artificial light
Explain the work of Vetter
What did this support
Participants were exposed to blue enriched light during their office hours and this synchronised their rhythms to their office hours
showing that light is the dominant EZ for the SCN
Define infradian rhythm
A type of biological rhythm that takes more than 24 hours to complete
Eg menstrual cycle
Explain the work of Stern and McClintock
Conducted a study showing how menstrual cycles might synchronised based of the influence of female pheromones
They did this by rubbing pheromones on the upper lip of a participant- 68% of women experienced changes in their cycle > bringing them closer to the cycle of the woman whose pheromones had been used
Supports role of endogenous pacemakers on infradian rhythms and also EZs which can impact the EPs too
What is a limitation of stern and McClintocks work
Small samples
Limited replication
Define ultradian rhythm
A type of biological rhythm with a frequency of more than one cycle in 24 hours
Eg REM
Name an experiment highlighting the importance of REM
Jouvet
Cats brains= woke them up during REM denying them of this stage of sleep
Cats got stressed n died
Explain the work of Dement and Kleitman
They monitored the brainwave activity through EEG and woke them up at different stages of sleep cycle
Those women up during REM could recall more dreams than those in NREM
suggests we go through different stages of sleep which supports ultradian rhythms
Suggest a limitation with Dement and Kleitmans work
Artificial
Small samples
Lack ecological validity
