Biopsychology Flashcards
How does the endocrine system transmit information?
Releasing hormones directly Into the blood stream via blood vessels
How quickly does the endocrine system act?
Slowly
How does the endocrine system control?
Indirectly
How long do the effects last?
Long term
What is the function of the endocrine glands?
To provide a chemical system of communication via the bloodstream. It also regulates the body’s internal physiological processes through the release of hormones
What are the endocrine glands?
Pituitary Thyroid Adrenal Pancreas Gonads
What is the role of the pituitary gland?
It is the “master gland” in the endocrine system. Many of the hormones released by the pituitary gland controls the secretions from other endocrine glands
What are the two main parts of the endocrine system?
Anterior (front)
Posterior (back)
What are the hormones released by the anterior of the pituitary and what is their role?
Adrenocorticotrophic (ACTH)- stress response, stimulating the adrenal glands to produce the hormone cortisol
Luteinising (LH) & FSH- control the reproductive functioning and sexual characteristics eg: stimulate ovaries
What are hormones released by the posterior of the pituitary gland and what is their role?
Oxytoxin- stimulates he contraction of the uterus during childbirth and also promotes mother-infant bonding
ADH- regulates water balance
What are the two parts of the adrenal glands?
Adrenal Medulla (inner) Adrenal Cortex (outer)
What does the adrenal medulla release and what effect does it have?
Adrenaline and noradrenaline- increases heart rate and blood flow to the muscles and the brain.
Releases stored glucose for energy in the flight or fight response
What does the adrenal cortex release and what effect does it have?
Glucocorticoid hormones (corti/sol/sone/costerone) regulating cardiovascular and anti-inflammatory functions. Coles with ongoing stress and suppression of the immune system
What are hormones
Chemical substances released from the endocrine glands into the bloodstream carried to target sites in the body
What cells can hormones have a direct affect on?
Cells with receptors for that particular hormone (target cells)
What happens when enough receptor sites are stimulated by hormones?
A physiological reaction occurs
What is crucial to the normal functioning of a hormone
Levels and timing of release. To much or too little at the wrong time can result in dysfunction of bodily systems
How is the endocrine system regulated?
Through the hypothalamus and Negative feedback
How does the hypothalamus regulate hormones
The hypothalamus controls the “master gland” the pituitary by secreting a releasing hormone eg: corticotrophin
How does the Negative Feedback System regulate the endocrine system
Hypothalamus shuts down the secretion of the releasing hormone when the levels are too high to maintain a stable concentration in the bloodstream
What does the endocrine system consist of?
Ducked glands
What is action potential
Information travelling away from the cell body in the form of an electrical signal
What does the process of synaptic transmission refer to?
Process by which a nerve impulse passes across the synaptic cleft from one neurone (presynaptic) to another (postsynaptic)
What is the synapse?
The small gap between neurone in which neurotransmitters are released, permitting nerve impulses to be transmitted between neurones
What does the synapse include?
End of presynaptic neurone
Membrane of postsynaptic neurone
Gap inbetween
What are neurotransmitters?
Chemical substance that transmits nerve impulses across a synapse
How are impulses transmitted across the synapse and how long does it take
Chemical and a fraction of a second
Where are the neurotransmitters stored for synaptic transmission
In synaptic vesicles
What stimulates the vesicles involved in synaptic transmission to release neurotransmitter
Action potential down the axon to axon terminal
How do neurotransmitters get over the gap to the postsynaptic membrane?
Diffuses across gap and then binds to special receptors
What varies across types of receptors in synaptic transmission
The nature of response
What does the synaptic transmission process produce on the postsynaptic neurone
Excitatory or inhibitory effects
What happens after synaptic transmission
Neurotransmitters are released back into the synaptic space and is then cleared from the synaptic cleft
Which processes are used to clear neurotransmitters from the synaptic cleft
Diffusion
Break Down
Re-uptake
What is the relationship between uptake and the effects of neurotransmitters
The quicker the reuptake, the shorter the effects on the postsynaptic neurone
What do some drugs do to prolong the effect of neurotransmitters
Inhibit the re-uptake process eg: SSRI the antidepressant
What are examples of neurotransmitters which have an excitatory effect on the postsynaptic neurone
Glutamate and noradrenaline
What do excitatory synaptic connections do to the neural activation in the CNS
Increase the neural activation
What does a excitatory neurotransmitter binding with a postsynaptic receptor cause?
An electrical change in the cell membrane resulting in an excitatory postsynaptic potential (EPSP) making the postsynaptic cell more likely to fire
What are examples of neurotransmitters that have an inhibitory effect on the postsynaptic neurone
GABA
What do inhibitory synaptic connections do to the neural activation in the CNS
Decrease neural activation
What does an inhibitory neurotransmitter binding wig a postsynaptic receptor?
Inhibitory postsynaptic potential IPSP making the postsynaptic cell less likely to fire
What can a nerve cell receive?
EPSPs and IPSPs influences from several neurtransmitters
What determines if a neutron fires?
The sum of all excitatory and inhibitory synaptic input for the postsynaptic cell
What are relay neurons?
Neurons within the CNS that interconnect different parts of the CNS and allow sensory and motor neurons to communicate with each other
What are motor neurons
Carry commands from CNS to skeletal muscles or glands which allowS control of movement and responses of internal systems.
What are sensory neurons?
They carry sensory information (funny that) from the body’s sensory receptors and sensory organs to the CNS. They convert information from the receptors to neural impulses
What is the basic underlying structure of a neuron?
Dendrites
Cell body
Axon
What do dendrites do?
Receive signals from other neurons or sensory receptors
What does the cell body do?
Control centre of the neuron
What dos the axon do?
Conducts nerve impulses away from the cell body and towards other neurons
What are neurons?
The specialised cells making up the nervous system, which conduct electrical Impulses
Hat is the nervous system divided into
Two main subsystems the central nervous system (CNS) and Peripheral nervous system
What is the CNS?
Consists of the brain and spinal cord which receives information from the senses and controls the body’s responses
What is the Peripheral Nervous System)
Part of the nervous that is outside the brain and spinal cord.
It comprises of nerve cells leading to and from the CNS.
What is the Peripheral Nervous System divided into?
The somatic nervous system and the autonomic nervous system
What does the somatic nervous system do?
Carries sensory and motor information to and from the CNS and controls voluntary movement of skeletal muscles
What does the autonomic nervous system do
Governs involuntary activity of internal body systems eg heartbeat and digestion
What is the CNS’s main functions
Control of behaviour
Rebut ion if the body’s physiological processes
What is the spinal cord?
A bundle of nerve fibres enclosed within the spinal column, connecting nearly all parts of the body with the brain
What is the main function of the spinal cord
To relay information between the brain and the rest of the body
What does the spinal cord consist of?
31 pairs of spinal nerves which divides into two roots one containing a sensory neuron allowing the transmission of sensory information to the brain and one root sighs motor neuron
What do circuits of nerve cells in the spinal cord also enable us to perform
Simple reflexes without direct involvement of the brain
What are the four main areas of the brain?
Cerebrum
Cerebellum
Diencephalon
Brain stem
What is the role of the brain stem?
Responsible for regulating automatic functions essential for life
Motor and sensory neurons travel through allowing impulses to pass between the brain and spinal cord
What is the role of the cerebellum
Sits beneath the back of the cerebrum and is involved in controlling motor skills, balance and coordinating muscles
What is the role of the diencephalon?
Has the thalamus which acts as a relay station for nerve impulses and the hypothalamus which regulates the body’s temperature, hunger and thirst. It acts as a link between the endocrine system and the nervous system
What is the cerebrum divided into?
The frontal lobe
The Parietal lobe
The occipital lobe
The temporal lobe
What is the role of the frontal lobe?
Involved in thought, speech production and learning
What is the role of the parietal lobe?
Processes sensory information eg touch, temperature and pain
What is the role of the occipital lobe
To process visual info
What is the role of the temporal lobe
Involved in hearing and memory
What is the autonomic system divided into?
The sympathetic and parasympathetic nervous system
What does the sympathetic NS produce?
Arousal, preparing the body for rapid reaction
What are ‘symptoms’ of the sympathetic NS
Increased heart rate, pupils become dilated
What does the parasympathetic NS do?
Reduces arousal, conserving energy and digestion
What are ‘symptoms’ of the parasympathetic NS
Decreased heart rate, increases stomach activity
What is the sympathetic NS involved in
The fight or flight response
What is the parasympathetic NS involved in
Rest and digest
What direction does the message travel in a neuron (on a page)
Left to right
What is involved in the fight or flight response
Amygdala
Hypothalamus
Adrenal medulla
Discuss the role of the Amygdala in the fight or flight response
Part of limpid system, detects fearful stimuli
Rapid without conscious awareness
Connect to the ANS to prepare body for response
Discuss the role of the hypothalamus in the fight or flight response
Communicates with rest of body through SNS
In stress response, triggers: SAM, HPA
Discuss the role of the adrenal medulla in the fight or flight response
Releases adrenaline and noradrenaline
Adrenaline boats supply of oxygen to the muscles and suppresses non-emergency bodily processes
Discuss the flow response to sudden stressors
Appraisal, hypothalamus, SAM, Adrenal Medulla, Adrenaline, Noradrenaline
Discuss the flow response to ongoing stressors
Hypothalamus, pituitary, adrenal, feedback
What are the gender differences in the fight or flight response
Taylor: tend or befriend evolved form being primary caregiver
Fleeing too soon threatens offspring
Fight harder due to oxytocin reducing fearfulness
What are the negative consequences to the flight or fight response
If repeatedly activated, causes physical damage eg: high blood pressure damages arteries and damage to cortisol affects the immune system
Discuss how the fight or flight response doesn’t tell the whole story
Freeze element which allows better appraisal of situation as we are hyper vigilant
Discuss how stress response is actually more positive
Acute stress enables bette teamwork eg: 9/11 human become protective and work together which is why we have thrived as a species
Discuss a genetic basis too sex differences
Lee and Harky: SRY gene in Y chromosome = aggression for fight or flight only in men
What is the definition of the fight or flight response
A sequence of activity within the body which is triggered when the body prepares itself for defending, attacking or running to safety. Involves changes in nervous system and secretion of hormones to sustain arousal
What does localisation of function refer to
Specific areas of the brain are associated with specific functions
Discuss the motor cortex
Voluntary movements
In frontal lobe
Both hemispheres, opposite control
Regions arranged logically
Discuss the somatosensory cortex
Processes input from sensory receptors that re sensitive to touch
Parietal lobe, post central gurus
Produces sensations
Both hemispheres, opposite control
Discuss the visual cortex
Occipital lobe
Begins in retina in back of eye
Terminates in thalamus, acts as relay station to visual cortex
Both hemispheres
Discuss the auditory cortex
Hearing
In temporal lobe
Both hemispheres
Cochlea, Brian stem, thalamus, auditory cortex
What are the language centres
Wernicke’s area and Broca’s area. Has arcuate fasciculus running between two
Discuss Wernicke’s area
Left temporal lobe
Comprehension of language
Discuss Broca’s area
Left frontal lobe
Speech production
Discuss support for localisation
Asphasia studies support language centres:
Broca’s asphasia- can’t produce language
Wernicke’s asphasia- can’t understand language
Discuss Equipotentiality theory
Basic motor and sensory functions localised t not hire mental functions
Lashley: intact areas responsible for cognitive functions following injury to area responsible
The effect of damage caused by the extent of damage rather than location
What is the criticism of localisation
How the brain communicates rather than which specific brain regions control a particular cognitive processes
What does hemispheric lateralisation refer to
2 halves of the brain are not entirely Like
Each hemispheres has function specialisation
Discuss split brain research
Corpus callous mallows hemispheric communication
Reforms to studies with individuals who have had surgical separations of hemispheres often due to severe epilepsy
Discuss Sperry& Gazzaniga’s procedure
Able to send visual info to one hemispheres at a time
Fixate in dot in centre which in for presented to left or right of visual fields
Asked to make responses with left or right hand or verbally
What did Sperry & Gazzinga find
Number of differences between two hemispheres
Hasn’t shown brain is organised into regions with specific tasks
Connectivity more importance than regions
What does brain plasticity refer to
Brains ability to modify its own structure and function as a result of experience
Discuss plasticity as a result of life experience
New experiences mean new nerve pathways becoming frequently stronger, if rarely used they die
Allows adaptation to environment
Age decreases cognitive functioning
What did Boyle found as a result of life experience and brain plasticity
60yr old leering to juggle had increases grey matter but when practice stopped changes reversed
Discuss playing video games and Brian plasticity
Deman complex cognitive and motor demands
Kuhn found an increase of grey matter in cortex, hippocampus and cerebellum when people trained on super Mario
What does video game training silt in
Synaptic connections for spatial navigation, strategic planning, working memory and motor performance
Discuss meditation and brain plasticity
Davidson: students who began mediating had increase in gamma waves but Tiebetan monks had greater amount
Monks show had meditation allowed permanent changes
What are gamma waves important for
Coordination of neurons
What does functional eco very after trauma refer to
Recovery of abilities and mental processes that have been comprised as a result of Brain injury or disease
What are two mechanisms for recovery
Neuronal masking
Stem cells
Discuss Neuronal Masking
Dormant synapses when have increased input to them damage surrounding brain area allowing them to become unblocked
Allows new connections to regions which aren’t usual,y activated and creates lateral spread of activation
Discuss stem cells as a mechanism for recovery
Directly replace dead or dying cells
Secrete growth factors to rescue injure cells
cells from neural network links an uninsured brain site, new stem cells are made with the he damaged region of the brain
Discuss animal studies in functional recovery
Kempermann: enriched environment could alter number of neurons in he brain, found increased number in rats if in complex environments rather than laboratory cages
Especially in hippocampus
Discuss plasticity support from human studies
Maguire: London taxi drivers MRI scans showed hippocampus volume was positively correlated with amount of time as taxi driver. Spatial navigation is highly used which was reflected in MRI scans
Discuss functional recovery support from animal studies
Tajiri, rats with traumatic Brian injury who had stem cells implanted into their Brian’s showed clear development of neuron-like cells in the area of injury
Discuss age differences in functional recovery
Huttenlocher, plasticity reduces with age but adults Cana don’t a child’s abilities with intense training. Suggests that there is plasticity but capacity for neural reorganisation is much greater in kids as adults require mass training
Discuss the nature of circadian rhythms
Driven by body clock
Synchronised by master circadian pacemaker SCN
Light provides main input to body clock
Light sensitive cells detect and send messages to SCN
What is the SCN
Suprachiasmatic Nuclei
Discuss the sleep-wake cycle
Light & dark are external signals Dips and rises at 2-4 am and 1-3pm Cycle und homeostatic control, tells us to sleep if awake for long time Internal 24hrs, free running Non tolerant of changes
What are two other circadian rhythms
Core body temperature
Hormone production
Discuss core body temperature as a circadian rhythm
Lowest at 4:30 AM, highest at 6PM
Sleep stats, temp decreases
Temp rises during final stages of sleep
Temp drop 2-4AM
Discuss hormone production as a circadian rhythm
Pineal gland in brain produces and releases melatonin
Peaks during darkness and encourages sleep
Production drops as we wake
Discuss Michael Striffe’s aim
To study free running circadian rhythms
Discuss Michael Striffe’s procedure
Lived underground for long periods of time with no external cue to guide his rhythms
Discuss Michael Striffe’s findings
61 days thought he lost 28days
6months went to 20hrs
As he got older body clicked more slowly
Dies research support for the role of light
Hughes: extreme variation in daylight in a particular change when hormonal levels peak, cortisol changed to noon not wake
Explains variation in circadian rhythms
Winter darkness had no change in cortisol
Discuss individual differences in circadian rhythms
Cycle length: vary between 13-65hrs (czeisler)
Cycle onset: innate differences for rhythm peak
Duffy: ‘morning people=early’ rise 6am, bed 10pm
‘Evening people =late’ rise 10am, bed 1pm
Discuss the research methodology
Thought that dim artificial light didn’t have effect, therefore wasn’t isolate as a variable, questions reliability of older studies
Czeisler: dim artificial light can alter rhythms between going down 22hrs to going up to 28hrs
Discuss ultradian rhythms sleep stages
Follows pattern of alternating between REM and NREM
5 stages of sleep: 4 NREM 1(5th) REM
Repeats 90-100mins
Each stage show own EEG pattern
Discuss the basic rest activity cycle
90mins, continuous throughout day
Progressing form a state of alertness to fatigue
After 90mins human body runs out of resources resulting in loss of concentration, fatigue and hunger
Discuss a weekly infraction rhythm
Grouping of 7days commonly used across world, may be due to biological factors
HALBERG: 7 day rhythms of blood pressure and heart rate in humans
Discuss monthly infradian rhythms
Menstrual cycle: 28days regulated by hormones either promoting ovulation or stimulating uterus
Discuss annual infradian rhythms
Related to seasons
SAD, seasonal variation in mood in human, depressed in winter months
Animals migrate
Discuss individual differences in sleep stages
Non-biological factors affecting individuals asleep patterns eg: room temp, sleep hygiene
Tucker: factor biologically determined, perhaps genetic
What individual differences did Tucker find in sleep stages
Sleep duration, time to fall asleep, amount of time in each sleep stage. We’re not driven by circumstance but partially biologically driven
Discuss research support for BRAC
Ericsson found elite violinist rehearse for max of 90mins
Violinist, athletes, chess players and authors often have naps after sessions
Discuss how the menstraul cycle may be controlled by exogenous cues
Usually endogenous
But- women with uninterrupted menstraul cycles through their swear can get other women to synchronise them through smell
Suggests cycle can be affected by pheromones
Discuss the belief in lunar rhythms
Mid-wives: more babies born on full moon (subjective association)
Mental health professional: full moon alters behaviour
Most studies fail to show this but occasional studies show correlation but no causal relationships
Highlights how Rams are biologically driven
What are endogenous pacemakers
Internal biological clocks in brain- the SCN which has own inbuilt circadian rhythm
How does the endogenous pacemaker function
Relieves info about light from optic nerve, keeps SCN circadian rhythm synchronised with daylight
Light dark rhythms make SCN send signals to pineal gland to control secretion of melatonin
What are two exogenous zeitgebers
Light and social cues
Discuss light as an exogenous zeitgebers
Receptors in SCN sensitive to light changes
Resets internal biological clock everyday
Rods and cones in retina detect light from visual images
Melanoma in detects natural light and sends signal to SCN to set daily body cycle
Discuss social cues as an exogenous zeitgebers
Mel times and social activity
Ashcroft, people can compensate for lack of natural light by response to social zeitgebers instead
Helps blind people
Prevents jet lag if people go outside and use social cues
Discuss support for the role of the SCN
Morgan- barred hamsters with. Abnormal circadian rhythms of 20hrs, transplanted them into normal hamsters who then displayed same abnormal rhythm.
Discuss separate rhythms which questions if the SCN is the master
Folkard: studied university students who lived in lab with no daylight of exogenous cues to reset SCN for 25dAys
After 25 days Coe them rhythm 24hes
Sleep-wake extended to 30hrs
Period of sleep longer than 16hrs
Discuss the role of the SCN in exogenous zeitgebers
Blind people have reliable circadian rhythms despite lack of rods and cones
Blind people who retain some log perception have normal circadian Rho but those without show abnormal rhythm
