Summary
BIOPSYCHOLOGY AQA SUMMARY NOTES
- Module
- A level Psychology
- Institution
- A Level Psychology
Covering all A01, A02 and A03 that could possibly come up in your exams!
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Nervous and endocrine system Neurones and synaptic transmission Localisation of function in the brain Hemispheric lateralisation and split brain researchKey features: nervous system is a specialised network Types of neurones: nervous systems primary Holistic theory replaced by localisation theory: in the Hemispheric lateralisation: the brain is lateralised and
of cells and our primary communication system. communication. early 19th century holistic theory suggested that all split into the left and right hemisphere.
Based on electrical and chemical signals. 1. Sensory neurones: carry messages along the PNS to parts of the brain were involved in processing thought Left = dominant for language
1. to collect, process and respond to information in the the CNS. They have long dendrites and short axons. and action. Specific areas of the brain were later linked Right = excels at visual motor tasks
environment. Located in the PNS in clusters called ganglia’s. with specific physical and psychological functions
2. to coordinate the working of different organs 2. Relay neurones: connect sensory neurones to motor (localisation theory). If an area of the brain is damaged
or other relay neurones. They have short dendrites then that function associated with that area is also Two hemispheres are connected by nerve fibres called
and short axons. 97% of neurones are relay and most affected. the corpus callosum which facilitates interhemispheric
Structure and function of the Central Nervous System are in the brain and visual system. communication allowing the LH and RH to communicate.
(CNS): CNS is made up of the brain and the spinal 3. Motor neurones: connect the CNS to effectors such
cord. The brain is the centre of conscious awareness. as muscles and glands. They have short dendrites and Hemispheres and lateralisation: Lateralisation is the
The outer layer of the brain (cerebral cortex) is highly long axons. Cell bodies may be in the CNS but long control of some physical and psychological functions in a Localised: some functions of the brain are localised and
developed and is what distinguishes our higher mental axons form part of the PNS. particular hemisphere. The left side of the body is appear in both of the hemispheres eg auditory,
functions from those of animals. controlled by the right hemisphere and the right side visual, motor and somatosensory
is controlled by the left hemisphere.
Structure of neurones: variation in size but they all share
Brain is divided into two hemispheres: left and right. the same structure. Localised and lateralised: two main language centres
Also divided into four lobes: frontal, parietal, temporal Cell body/soma: includes a nucleus which contains the Cerebral cortex: outer layer of the brain covering the are in the LH and RH. RH produces rudimentary words
and occipital. genetic material of the cell inner parts. Around 3mm thick and is what separates us but provides emotional context. LH may be the analyser
Frontal: high abstract functions Dendrites: branchlike structures that protrude from the from lower animals as it is highly developed. Cortex and RH the synthesiser.
Parietal: information from senses + spatial navigation cell body. These carry nerve impulses from appears grey due to the location of cell bodies (grey
Temporal: auditory information neighbouring neurones towards the cell body. matter).
Occipital: visual information Contralateral: in the motor area, the right hemisphere
Axon: carries the electrical impulse away from the cell
controls the left side of the body and vice versa. Cross
body down the length of the neurone. Covered in a fatty
Division of Cerebral cortex into four lobes: wired.
layer of myelin sheath that protects the axon. Gaps in
The spinal cord is an extension of the brain and is the axon called nodes of Ranvier speed up the rate of 1. motor cortex: back of the frontal lobe of both
responsible for reflex actions. It passes messages to transmission. hemispheres. Controls voluntary movement and
and from the brain and connects nerves to the PNS. damage may result in loss of control of fine motor Contralateral and ipsilateral: left visual field (LVF) of
Terminal buttons: communication with the next neuron I both eyes is connected to the RH and right visual field
the chain across the synapse. movements.
2. somatosensory cortex: front of parietal lobes and (RVF) of both eyes is connected to the LH.
Structure and function of the Peripheral Nervous System processes sensory information from the skin eg heat. Enables the visual areas to compare the slightly different
(PNS): transmits messages via millions of neurons to Amount of somatosensory cortex are devoted to a perspective from each eye and aids depth perception.
Electrical transmission: when a neurone is in a resting
and from the nervous system. particular body part denotes its sensitivity. Same arrangement for auditory areas.
state the inside of the cell is negatively charged
1. Autonomic nervous system: governs vital functions compared to the rest of the cell. 3. visual cortex: in the occipital lobe and each eye
in the body eg breathing, heart rate, digestion, sexual sends information from the right visual field to the left
arousal, and stress responses. Sperry 1968 Split brain research:
visual cortex and the left visual field to the right
2. Somatic nervous system: governs muscle Procedure: two hemispheres were surgically separated
When it has been activated, the inside of the cell visual cortex.
movement and receives information from sensory by cutting the corpus collosum. Used to treat severe
becomes positively charged for a split second causing 4. auditory cortex: in the temporal lobe and analyses
receptors. epilepsy. 11 split brain patients were studied. Images
an action potential to occur. This creates an electrical speech-based information. Damage may produce partial
or words were projected to RVF (processed by LH) and
impulse that travels down the axon towards the end of hearing loss – the more extensive the damage the more
the same or different image was projected to the LVF
the neuron. serious the loss.
ANS divides into the sympathetic and (processed by the RH). Presenting the image to one
parasympathetic nervous system. hemisphere meant that the information could not be
Sympathetic is typically involved in flight or fight Language centres: Broca and Wernicke conveyed to the other hemisphere.
responses. Impulses travel from here to organs to Broca + Speech production: identified by Broca in the Findings and conclusions:
help prepare for actions in a dangerous situation. 1880s in the left frontal lobe. Damage to this area If the object was shown to the RVF than the ptp could
Parasympathetic relaxes the body and returns us to a causes Broca’s aphasia which is characterised by describe what they saw.
state of normal. Slows down heart or breathing rate and speech that is slow, laborious and lacking in fluency. If the object was shown to the LVF than ptp would not be
any previously slowed processes are sped up again. Patients may have difficulty finding words and naming able to name, the object (no language centres in the
certain objects. As well as prepositions eg and. RH). However, they can select the matching object
Wernicke + language understanding: identified by behind the screen using their left hand. They could also
Wernicke in the 1880s in the left temporal lobe. Patients select objects closely associated with the picture.
with Wernicke aphasia produces language but has Demonstrates how certain functions are lateralised
problems understanding it, they produce fluent but in the brain, and shows that the LH is verbal and the
meaningless speech. Often produce nonsense words RH is silent but emotional.
(neologisms) as part of their speech.
Broca and speech production case study: Tan Sperry 1968 Split brain research
Phineas Gage: working on a railroad when a tamping
, iron shot through his cheek taking a chunk of his frontal
lobe. Lead to a personality change.
Key features of the endocrine system: works alongside Synapse: each neurone is separated from the next by an + Support from neurosurgery: neurosurgery is used to + Evidence of lateralised brain functions in normal
the nervous system to control vital functions in the body extremely tiny gap treat mental disorders eg cingulotomy and involves brains: PET scans show when normal ptps attend to
along the action of hormones. Works more slowly than isolating the cingulate gyrus – dysfunction of this area global elements of an image, the RH is more active.
the nervous system but has a more widespread and may be a cause of OCD. Dougherty et al (2002) When required to focus on the finer detail the
powerful effect. Chemical transmission: signals within neurons are studied 44 people with OCD who had a cingulotomy. specific areas of the LH tend to dominate (Fink et al
transmitted electrically, but signals between neurons At follow up, 30% met the criteria for successful 1996). This suggests that hemispheric lateralisation is a
are transmitted chemically across the synapse. response and 14% for partial response. Success of feature of the normal brain as well as the split brain.
Glands: organs in the body that produce hormones. Key When the electrical impulse reaches the end of the such procedures suggests that behaviours associated
gland is the pituitary gland located in the brain and it neurone (presynaptic terminal) it triggers the release of with serious mental disorders can be localised.
is called the master gland because it controls the neurotransmitter from tiny sacs called synaptic - Analyser versus synthesiser brain may be wrong:
release of hormones from all the other endocrine vesicles. There may be different functions in the RH and LH but
glands. Once a neurotransmitter, crosses this gap it gets taken + Evidence of brain scan to support localisation research suggests people do not have a dominant side
Pineal gland: responsible for important biological up by a postsynaptic receptor site on the next neuron. theory: Peterson et al (1988) used brain scans to creating a different personality. Nielsen et al (2013)
rhythms eg sleep wake cycle Impulse only ever travels in one direction. show activity in Wernicke’s area during a listening analysed 1000 brain scans, finding people did use
Hypothalamus: stimulates and controls release of task and in Broca’s area during a reading task. A certain hemispheres for certain tasks but no
hormones from pituitary gland study of LTM by Tulving et al (1994) revealed semantic dominance. This suggests that the notion of right or left
Adrenal gland (medulla and cortex): flight or fight Neurotransmitters: chemicals that diffuse across the and episodic memories are located in different parts of brained people is wrong eg artist brain.
response synapse next to the next neurone in the chain. the prefrontal cortex. Now a number of sophisticated
Thyloid: responsible for regulating metabolism Each neurotransmitter has its own specific molecular methods for measuring activity in the brain, providing
Ovaries: controls regulation of female reproduction structure that fits perfectly into the postsynaptic sound scientific evidence of localisation of function. Lateralisation vs plasticity: Lateralisation is adaptive,
including menstrual cycle and + pregnancy receptor site. CA: Lashley removed areas of the cortex (up to 50%) in enabling two simultaneous tasks with greater efficacy eg
Testes: responsible for development of male sex Eg Acetylcholine (Ach) found where a motor neuron rats learning the route through a maze. Learning only lateralised chickens were better at finding food
characteristics during puberty meets a muscle, causing muscle contraction. required all of the cortex rather than being confined to a while watching for predators (Rogers et al 2004). On
particular area. Suggests there are higher cognitive the other hand, neural plasticity is also adaptive. After
processes eg learning are not localised but distributed in damage to the brain, language function can swap
Hormones: hormones are secreted in the bloodstream Excitation and inhibition: neurotransmitters generally a more holistic way. sides (Holland et all 1996). Suggests that lateralisation
and affect any cell in the body that has a receptor for either have an excitatory or inhibitory effect on the is first preference but ultimately plasticity is more
that particular hormone. Eg thyroxine produced by the neighbouring region. important because it deals with the loss of lateralisation.
thyroid gland affects cells in the heart and also cells Adrenaline: generally excitatory, increasing the positive - Language localisation model has been questioned:
throughout the body which increases metabolic rates. charge of the postsynaptic neurone, making the Dick and Tremblay (2016) found that very few
Affects growth rates. postsynaptic neurone fire. researchers still believe language is only in Broca’s + Support from more recent brain split studies: Luck
Serotonin: generally inhibitory, increasing the negative and Wernicke’s area. Advanced techniques eg fMRI et al (1989) showed that split brain ptps are better than
charge of the postsynaptic neurone, making it less likely have identified regions in the right hemisphere and the normal controls eg twice as fast as identifying the odd
Endocrine and ANS working together/flight or fight: the postsynaptic neurone will fire. thalamus. This suggests that rather than being confined one out in an array of similar objects. In the normal
stressor is perceived by hypothalamus which activates Dopamine: unusual neurotransmitter as it is equally to a couple of key areas, language may be organised brain, the LH’s superior processing abilities are watered
the pituitary. SNS is aroused and adrenaline is likely to have an inhibitory or excitatory effect. more holistically in the brain, which contradicts the down by the interior right hemisphere (Kingstone et al
released from the adrenal medulla into the language localisation model. 1995). This supports Sperry’s earlier findings that the left
bloodstream. This delivers the aroused state causing brain and right brain are distinct in terms of functions
changes in target organs in the body eg heart rate, Summation: and abilities.
dilation of pupils (flight or fight response). 1. temporal summation: two or more action potentials - Case study evidence: Unique cases of neurological
arrive in rapid succession along a single presynaptic damage support localisation theory eg Phineas Gage
neurone. who lost some of his brain in an explosion and his - Casual relationships are hard to establish: In
Immediate or automatic response – response happens 2. spatial summation: two or more inputs arrive from personality changed. However, it is difficult to make Sperry’s research, the behaviour of split brain ptps was
the instant a threat is perceived. different presynaptic cells to the same synapse at the meaningful generalisations based on a single individual compared to a neurotypical control group. However,
same time. and conclusions may depend on the subjective none of the control group had epilepsy. Any differences
interpretation of the researcher. Suggests some between the groups may be due to epilepsy not the split
Parasympathetic nervous system takes over once the evidence supporting localisation, may lack validity, brain (confounding variable). Means that some of the
threat has passed, returning the body to its natural Excitatory and inhibitory influences are summed and
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