Biopsychology Flashcards
What are the two parts of the human nervous system?
Central Nervous System (CNS) and Peripheral Nervous System (SNS)
What structures make up the CNS?
Brain and spinal cord
What is the function of the CNS?
Origin of all complex commands and decisions – connects the nerves of the peripheral nervous system to the brain and spinal cord.
What type of action is controlled from the spinal cord?
Reflex actions
What is the function of the peripheral nervous system?
Sends information from receptors (outside info) to the CNS, and transmits information from the CNS to the effectors (muscles or glands)
What are the two subsections of the peripheral nervous system?
Autonomic Nervous System and Somatic Nervous System
Which part of the nervous system is the autonomic nervous system part of?
Peripheral nervous system
Which part of the nervous system is the somatic nervous system part of?
Peripheral nervous system
What is the function of the somatic nervous system?
Carries sensory and motor information to and from the spinal cord, controls voluntary muscle movement
What is the function of the autonomic nervous system?
Transmits information to and from internal bodily organs, controls automatic involuntary processes like breathing/heart rate etc.
What are the two branches of the autonomic nervous system?
Sympathetic and Parasympathetic
Which part of the nervous system is the sympathetic nervous system part of?
Autonomic nervous system
Which part of the nervous system is the parasympathetic nervous system part of?
Autonomic nervous system
What is the role of the sympathetic nervous system?
Prepares the body to expend energy e.g. for fight or flight
What is the role of the parasympathetic nervous system?
State in which the body maintains body functions and conserves energy as much as possible
What takes place in the body when it is in the sympathetic state?
Digestion inhibited, saliva production inhibited, blood diverted from surface of the skin, energy release focused on heart and lungs to prepare body for action, pupils dilate
What takes place in the body when it is in the parasympathetic state?
Digestion increases, saliva production increases, heart rate decreases, pupils constrict
What is a neuron?
A nerve cell that transmits messages as an electrical signal
What are the branch-like structures that stick out from the cell body and carry impulses from neighbouring neurons towards the cell body?
Dendrites
What is the name of the fatty layer that protects the axon and speeds up electrical transmission?
Myelin Sheath
What is the axon?
The branch extending from the cell body that carries impulses away from it towards the terminal buttons.
What is the purpose of the nodes of ranvier (gaps between the myelin sheath)?
Speeds up the signal transmission
What are the three types of neuron?
Sensory, Relay, Motor
What is the role of the sensory neuron?
Carries messages from the peripheral nervous system (receptors) to the central nervous system
What are the axon and dendrite lengths like on a sensory neuron?
Long dendrites, short axons
What is the role of a relay neuron?
Transfers messages from sensory neurons to other relay or motor neurons
What are the axon and dendrite lengths like on a relay neuron?
Short dendrites, short axons
What is the role of a motor neuron?
Carries messages from the central nervous system to effectors (muscles and glands)
What are the axon and dendrite lengths like on a motor neuron?
Short dendrites, long axons
What are the stages of the reflex arc? Use as many specialist terms as possible.
Stimulus detected by sense organs (receptors) in peripheral nervous system, Sense organs cause signal to be sent along sensory neuron and into the central nervous system, Sensory neuron synapses (connects) with a relay neuron, Relay neuron synapses with a motor neuron, Motor neuron carries signal to an effector, Effector carries out reflex response
How are signals within neurons transmitted?
Electrically
How are signals between neurons transmitted?
Chemically
What is a synapse?
The gap between neurons
Describe the process of synaptic transmission. Use as many specialist terms as possible.
Electrical impulse reaches the terminal button of the axon of the presynaptic neuron. This triggers the release of neurotransmitters from synaptic vesicles. Neurotransmitters diffuse across the synaptic cleft (from high to low concentration). Neurotransmitters bind with the receptor sites on the dendrite of the postsynaptic neuron. Influence of excitatory and inhibitory neurotransmitters undergo summation to determine if an electrical signal is generated or stopped in the postsynaptic neuron. Neurotransmitters are released from the receptor sites and are broken down or reabsorbed by the presynaptic neuron.
What are neurotransmitters?
Chemical messengers that diffuse across synapses, can be excitatory or inhibitory.
What effect does an excitatory neurotransmitter have?
It increases the positive charge in the neuron making it more likely to fire.
What effect does an inhibitory neurotransmitter have?
It increases the negative charge of the neuron making it less likely to fire.
What is the endocrine system?
Collection of gland and hormones that regulate metabolism, growth and development, sexual function, sleep, mood etc.
What is the main difference between the endocrine system and the nervous system?
Endocrine system controls slow processes, nervous system controls much faster processes.
What is a gland?
An organ in the body that creates a substance such as hormones
Give an example of a gland and its function
Any from; Thyroid gland – produces thyroxine that increases metabolism. Testes – produce testosterone that controls secondary sexual characteristics in males, and sperm production. Ovaries – produce oestrogen and progesterone that controls the menstrual cycle in females. Pancreas – produces insulin that controls blood sugar levels. Pituitary gland – master gland that controls all other glands, produces hormones like follicle stimulating hormone involved in the control of the menstrual cycle. Adrenal glands – adrenaline and cortisol control the fight or flight and stress responses.
What is a hormone?
Chemical substance secreted into the bloodstream that affects target organs (have cells with the correct receptors)
What is the role of the adrenal glands?
Release adrenaline to prepare the body for the fight or flight response, causes constriction of blood vessels in the digestive system to divert blood supply to the heart and lungs.
What are the stages of the fight or flight response?
Stressor identified. Hypothalamus triggers the autonomic nervous system to change from parasympathetic to sympathetic state. Adrenaline released from the adrenal medulla into the bloodstream. Adrenaline triggers physiological changes in target organs. Once threat has passed the parasympathetic nervous system returns the body to resting state.
Define localisation of function
The theory that different parts of the brain are responsible for different behaviours, processes or activities.
What are the two sides of the brain called?
Hemispheres
What are the four lobes of the brain?
Frontal, parietal, occipital and temporal
What is the outer layer of the brain called?
Cortex
What system is found within the middle of the brain?
Limbic system – made up of amygdala, hypothalamus and thalamus – critical for memory formation and emotional processes
What are the ridges of the brain called?
Gyrus/gyri
What are the troughs/dips in the brain called?
Sulcus/sulci
What is white matter in the brain made up of?
Axons
What is the grey matter in the brain made up of?
Cell bodies of neurons
What is the job of the hippocampus?
One on each side of the brain, responsible for consolidation of learning/memory, and spatial memory/navigation.
What is the hypothalamus?
The structure in the brain that links the nervous system and endocrine system through control of the pituitary gland.
What is the motor area of the brain and where is it?
Back of frontal lobe, involved in regulating movement
What is the somatosensory area of the brain and where is it?
Front of the parietal lobe, processes sensory information such as touch
What is the visual area of the brain and where is it?
In the occipital lobe, receives and processes visual information
What is the auditory area of the brain and where is it?
Temporal lobe, concerned with analysis of speech based information.
Where is Wernicke’s area and what does it do?
Temporal lobe of left hemisphere. Understanding of language
Where is Broca’s area and what does it do?
Frontal lobe of left hemisphere. Speech production
What was Peterson et al’s brain scan evidence for localisation of function, specifically language?
Demonstrated that Wernicke’s area was active during a listening task whilst Broca’s area was active during a reading task – showing they are responsible for different functions.
What was Tulving’s evidence showing memory may demonstrate localisation of function?
Showed that long term memory is split and semantic and episodic memories are in different parts of the prefrontal cortex.
Who found evidence against localisation of function? How?
Lashley, Rats learning a maze could have up to half of their cortex removed (different parts) and could still learn the maze showing that learning isn’t happening in just one place – not localised
What is the alternative theory to localisation of brain function?
Holistic theory, equipotentiality
What is a compromise between localisation of function and holistic theory of brain function?
Some processes are more localised than others – more complex processes (like learning) involved multiple areas of the brain.
What is brain plasticity?
The brain’s tendency to change and adapt as a result of learning and experience
What is functional recovery?
A specific type of brain plasticity – occurs following a trauma
What 3 processes be involved in functional recovery?
Axonal sprouting, recruitment of homologous areas, reformation of blood supply
What is the taxi driver evidence for plasticity?
Maguire – significantly more grey matter in the posterior hippocampus of taxi drivers than a control group, an area important for spatial memory and navigational skills, result of use and training for ‘the knowledge’
What is hemispheric lateralisation? Give an example.
The idea that certain mental processes or behaviours are controlled or dominantly controlled by one hemisphere rather than the other. Language on the left, facial recognition on the right, right controls left side movement, left controls right side movement
What is the corpus callosum?
The band of neural fibres (white matter) that connects the left and right hemispheres of the brain.
What has happened to a split brain patient?
They have had their corpus callosum cut (commissurotomy), usually as a last resort for relieving severe epilepsy.
What is the name of the set up used to experiment with split brain patients and how did it work?
Tachistoscope – allowed visual stimuli to be presented to just one visual field of the split brain patient.
If an image or word is presented to a split brain patient’s right visual field they can…
Name it (verbally)
If an image or word is presented to a split brain patient’s left visual field they can…
Draw it or select a matching object from a selection (using their left hand)
If a face is shown to a split brain patient’s left visual field…
They can correctly choose the face from a selection
If a face is shown to a split brain patient’s right visual field…
They will struggle to identify it
The problems with the split brain research are…
Small sample, Different levels of severing, Varied time since surgery – possibility of some functional recovery? Artificial task – in real life patients can just make use of both eyes –> exaggerating the differences
What are the 4 ways of studying the brain that you should know?
fMRI, post mortems, EEGs and ERPs
What is an fMRI, what does it measure?
Functional magnetic resonance imaging, Measures brain activity by detecting associated changes in blood flow
What is an EEG, what does it measure?
Electroencephalogram, Records the electrical activity of millions of neurons producing brain wave patterns that can be characteristic of specific states/behaviours e.g. stages of sleep
What is an ERP, what does it measure?
Event related potentials, Statistical averaging techniques used on EEGs to try and isolate specific responses of neurons to specific stimuli or tasks.
How do we use post-mortems in psychology?
Compare brains to ‘neuro-typical’ brains to identify differences and try to correlate these abnormalities to behaviours seen before death.
What are circadian rhythms?
Natural cycles that occur once every 24 hours
Give an example of a circadian rhythm.
Sleep-wake cycle, Body temperature
What are infradian rhythms?
Natural cycles that occur less than once every 24 hours (longer cycles)
Give an example of an infradian rhythm.
Menstrual cycle, Seasonal affective disorder
What are ultradian rhythms?
Natural cycles that occur more than once every 24 hours (short cycles)
Give an example of an ultradian rhythm.
Sleep cycle (stages of sleep)
What are exogenous zeitgebers?
External cues in the environment that entrain our endogenous rhythms
What are endogenous pacemakers?
Internal body clocks that regulate our biological rhythms
What does ‘entrain’ mean in the context of biological rhythms?
This is how external factors can be used to adjust our rhythms via our endogenous pacemakers
Name the key exogenous zeitgebers for the sleep wake cycle.
Light, social cues e.g. meal times, alarm clocks, working day
Name the endogenous pacemaker thought to control our sleep-wake cycle.
SCN – suprachiasmatic nucleus
What is melatonin?
Chemical produced by the pineal gland at night, required for sleep.
How is melatonin production affected by light?
(Blue) light inhibits the production of melatonin from the pineal gland, this maintains wakefulness. When (blue) light levels drop, melatonin can be produced inducing sleep.
What support is there for the role of exogenous zeitgebers in controlling our circadian rhythms?
Siffre, caves – absence of light -> increasing the length of his circadian rhythm. Aschoff and Weaver, WWII bunker – absence of light -> increasing length of circadian rhymts
What is the major criticism of the studies into light effects on circadian rhythms (e.g. Siffre, Aschoff and Weaver)?
The participants had access to artificial light, Czeisler showed that artificial light appears to reset biological rhythms
What is the problem for circadian rhythms research caused by night owls and larks?
There are individual differences in the natural preferences of individuals, mediated by genes like Per1, meaning that we are oversimplifying our models/explanations of circadian rhythms.
What evidence is there that exogenous zeitgebers can affect infradian rhythms?
Synchronising menstrual cycles (Stern and McClintock). Light therapy for treating SAD
Who first found EEG evidence for the stages of sleep?
Dement and Kleitman
What is brain activity like in each stage of sleep (wave type/speed etc.)?
1 – alpha waves, slower and more rhythmic than when awake, 2 – sleep spindles and theta waves 3&4 – Slow wave sleep - delta waves, slower waves with larger amplitude 5 – activity similar to when awake
How easy is it to wake people in stages 1 to 4? What do we observe in stage 5?
1 –, easy to wake people, 2 – easy to wake people, 3&4 – difficult to wake people, 5 – REM
Which stage of sleep is correlated with dreaming?
5 – Rapid Eye Movement (REM) sleep
