Y2 Module 2 - Biopsychology

Question 1

What are the 2 divisions of the human nervous system?

Answer 1

Peripheral and Central Nervous System.

Question 2

What is the function of the peripheral nervous system?

Answer 2

Transmits messages to and from the CNS.
Further divided into ANS (governs vital functions) and SNS (controls muscle movement and receives information from senses).

Question 3

Distinguish between the somatic nervous system and the autonomic nervous system.

Answer 3

Two sub-divisions of the PNS - ANS governs vital functions e.g. heartrate and breathing. SNS controls muscle movement and receives information from senses.

Question 4

What is the role of adrenaline in the fight or flight response?

Answer 4

Adrenaline triggers physiological changes in the body (e.g. increased heart rate), which are necessary for for the fight or flight response.

Question 5

What is meant by the endocrine system?

Answer 5

The Endocrine system works alongside the nervous system to control vital functions in the body. The endocrine system works much more slowly than the nervous system, but has very widespread effects. It is responsible for instructing various glands to release hormones into the bloodstream.

Question 6

The endocrine system is made up of a number of different glands which release hormones. Define the term gland. Give one example.

Answer 6

A gland is an organ in the body which synthesizes substances such as hormones. The thyroid gland, for example, produces thyroxine which affects cells in the heart (increasing heart rate). It also affects cells throughout the body, affecting metabolic rates (growth).

Question 7

What does the term hormone mean? Give an example.

Answer 7

Chemical substances that circulate in the bloodstream and only affect target organs. They are produced in large quantities, but disappear quickly. Their effects are very powerful.

Question 8

Outline one difference between the nervous system and the endocrine system.

Answer 8

One difference between the two is the time it takes for the systems to respond to stimuli. The nervous system reacts from electrical and chemical transmission and the response is near instantaneous. The endocrine system reacts much more slowly, but therefore much longer lasting and widespread effects.

Question 9

Explain the actions of the autonomic nervous system in the fight or flight response.

Answer 9

Hypothalamus triggers the sympathetic nervous system. The adrenal medulla releases adrenaline into the blood. Physiological changes in the body. When the threat has passed the parasympathetic branch activates. This returns the body back to its normal resting state.

Question 10

What is a neuron?

Answer 10

Neurons are nerve cells that process and transmit messages through electrical and chemical signals in the nervous system.

Question 11

Outline the function of a motor, relay and sensory neuron.

Answer 11

Motor neurons connect the central nervous system to effectors such as muscles and glands. Relay neurons connect the sensory neurons to motor neurons and other relay neurons. Sensory neurons carry messages from the peripheral nervous system to the central nervous system.

Question 12

Describe the structure of a neuron.

Answer 12

The cell body of a neuron includes the nucleus which contains the genetic material of the cell.
Dendrites are branch-like structures that carry nerve impulses from neighbouring neurons towards the cell body.
The axon carries impulses away from the cell body down the length of the neuron.
The myelin sheath covers the axon to protect and speed up electrical transmission of the impulse.
Nodes of ranvier are the gaps between the myelin sheath these speed up the transmission of impulses by forcing the impulse to jump across the gaps.
Terminal buttons are at the end of the axon, these communicate with the next neuron across the synapse.

Question 13

Outline the difference between electric and chemical transmission in relation to neurons.

Answer 13

Electric transmission happens within the neuron. This changes the neuron from being negatively charged to positively charged when activated by a stimulus. This then creates the electrical that travels to the end of the neuron.

Question 14

Explain the function of a neurotransmitter and give an example.

Answer 14

A neurotransmitter is a chemical released from the presynaptic nerve that relays a signal across the synapse. The neurotransmitter diffuses across the synapse and is taken up by the postsynaptic receptor site. The chemical message is then converted back into an electrical impulse. For example acetylcholine is found where the motor neuron meets a muscle and cause the muscle to contract.

Question 15

With reference to the process of synaptic transmission, explain what is meant by inhibition and excitation.

Answer 15

Serotonin has an inhibitory effect of the receiving neuron by causing the neuron to become more negatively charged which results in it being less likely to fire the electrical impulse. However, adrenaline’s an excitatory effect on the neuron by making it more positively charged which results in it being more likely to fire the electrical impulse.

Question 16

What are the four lobes of the cerebral cortex?

Answer 16

Frontal Lobe, Parietal Lobe, Occipital Lobe, Temporal Lobe.

Question 17

What are the four areas of cortical specialisation in the brain?

Answer 17

Motor Cortex - Voluntary Movement.
Somatosensory Cortex - Information related to the skin.
Visual Cortex - Information from the eye - left visual field to right cortex.
Auditory Cortex - speech based information.

Question 18

Outline the contribution of scientists such as Brocca and Wernicke to our understanding of the brain.

Answer 18

Established the areas of language in the brain.
Broca’s area = left frontal lobe - Speech production.
Wernicke’s area = left temporal lobe - Speech understanding / coherence.

Question 19

Outline 1 study in which localisation of function in the brain has been investigated.

Answer 19

Peterson et al. (1988). Used brain scans to show how Wernicke’s areas was active during a listening task and Broca’s area during a reading task → different functions.
Tulving 1944 - showed that episodic and semantic memory are located in different parts of the prefrontal cortex.

Question 20

Provide 2 pieces of supporting evidence for localisation of the brain - include research details.

Answer 20

Neurosurgical Evidence. Dougherty (2002). 44 OCD patients underwent a cingulotomy → at a 32 week check up almost half of the patients had made either a partial or successful recovery. Suggests the behaviour and symptoms for mental illness are localised.
Case Study evidence. Phineas Gage - steel rod through the brain removing a lot of the left frontal lobe. Change of personality → turned rude, quick tempered, aggressive. Suggests localisation in the brain.

Question 21

What is meant by plasticity and why does it challenge the idea of localisation?

Answer 21

When the brain becomes damaged and a particular function has been lost, the brain appears to be able to reorganise itself to recover function. Basically another part of the brain takes over the function. The brain physically adjusts the location of function if damage occurs, which suggests that localisation is not fixed to specific areas. The brain is working as a whole unit rather than specific areas for specific functions.

Question 22

What is meant by plasticity?

Answer 22

The tendency of the brain to change and adapt as a result of experience. The experiences that we have result in some connection being lost and other being strengthened.

Question 23

Outline some research into plasticity.

Answer 23

Maquire et al. (2000) - london taxi drivers. More grey matter in their posterior hippocampus → spatial and navigational skills. The “knowledge”. Brain structure is altered.

Question 24

How has research into brain plasticity helps us in the ‘real world’?

Answer 24

Neurorehabilitation. Physiotherapy following illness or injury e.g. motor therapy and electrical stimulus after stroke. Brain may be able to ‘fix’ itself.

Question 25

What is meant by functional recovery?

Answer 25

A form of plasticity. After a trauma, the brain’s ability to redistribute functions usually performed by the damaged area to undamaged areas.

Question 26

What happens in the brain during functional recovery.

Answer 26

Secondary neural pathways are activated to carry out certain functions. Axonal sprouting. Growth of new nerve endings which connect with undamaged nerve cells to create new pathways. New blood vessels. Recruitment of similar areas. E.g. Broca’s area damaged on the left side, the equivalent would be recruited on the right.

Question 27

Outline one example of animal research into functional recovery and discuss whether what we learn from such studies is worth the permanent damage does to the animals.

Answer 27

Hubel & Wiesel (1963). Cats eyes sewn shut and both visual cortices took over. Generalisability from cats to humans is an issue. We have no insight into thoughts or emotions. Plasticity may be different in animals.

Question 28

Are there any downsides to functional recovery and plasticity?

Answer 28

Negative plasticity. Maladaptive - drug use → poor cognitive functioning. Cognitive impairment and dementia (Medina et al, 2007). Phantom limb syndrome (Ramachandran, 1998).

Question 29

What other factors have been found to influence functional recovery?

Answer 29

Level of education - Schneider et al. (2014). The amount of time spent in education (greater cognitive reserve) - the bigger a patient’s chances of DFR. 40% of PPTs who achieved DFR had been in education for 16+ years. 10% of PPTs with 12 years or less achieved DFR.

Question 30

What is meant by hemispheric lateralisation?

Answer 30

Two halves of the brain function differently. Certain mental and processes and behaviours are controlled by one hemisphere rather than the other.

Question 31

Outline the key study conducted by Sperry (1968). Include the aim, procedure and 2 key findings.

Answer 31

Studied a group of individuals who had their corpus callosum severed → allowed Sperry to investigate if the two hemispheres were specialised for certain functions. Image or words would be projected to the right or left visual field → normally the information would be shared over both hemispheres.
Finding 1: Images presented in the left field could not be described.
Finding 2: Although they could not describe objects in the left field, they could identify them by touch.
Finding 3: Composite words - PPTs would use their left hand to write the word in their left visual field, but would say the word in their right visual field.
Finding 4: Matching face - the right hemisphere seems dominant in facial recognition.

Question 32

Briefly evaluate the methodology used in split-brain research.

Answer 32

Standardised procedure. Only showed images for 1 tenth of a second → patient would not have time to use both eyes. Well controlled procedure.

Question 33

Why are there issues with generalisation in Sperry’s research?

Answer 33

Only 11 people took part in the study. All had epilepsy → may have impacted the brain and the findings. The levels of disconnection was different in all the participants. The control group has no epilepsy → inappropriate as they differ from the experimental group in two ways - a control group of epileptics with split brains would have been better.

Question 34

The conclusions drawn from Sperry’s research are key contributors to our understanding of brain processes. Explain these conclusions.

Answer 34

Left hemisphere = analytical and verbal tasks; right = spatial and music. Right hemisphere = only rudimentary words, but contributes emotional and holistic content. Left hemisphere is the analyser and the right is the synthesiser → a key contribution to our understanding of the brain processes.

Question 35

Explain why the differences in function may be overstated.

Answer 35

Although the verbal and non-verbal labels of the left and right hemispheres can be useful - however the distinction is less clear cut. In a normal brain the two hemispheres are in constant communication when performing tasks. Many behaviours typically associated with one hemisphere can be carried out by either hemisphere if the situation should call for it.

Question 36

Name 4 ways of investigating the brain.

Answer 36

fMRI, EEG, ERPs, post mortems.

Question 37

Outline fMRIs as a way of investigating the brain.

Answer 37

Monitors blood oxygenation and flow in the brain. As areas become more active they require more oxygen. Allows us to localise function.

Question 38

Outline one strength and one limitation of fMRI scans as a way of identifying localisation of function in the brain.

Answer 38

Good Spatial resolution.
Bad Temporal resolution.
Low radiation - risk free and non-invasive.
Cannot hone in on neural activity.
People have to lay still.

Question 39

Describe what an EEG is.

Answer 39

A record of tiny electrical impulses produced by brain activity. By measuring characteristic brain patterns certain conditions of the brain can be measured e.g. epilepsy.

Question 40

Explain one strength and one limitation of EEGs.

Answer 40

Helped in diagnosing disorders such as epilepsy.
Helped in understanding stages of sleep.
Very high temporal resolution.
Generalised nature of the data.
Not good for pinpointing exact sources of data.

Question 41

Explain why a fMRI scan might be a more useful way of investigating localisation of function in the brain than an EEG.

Answer 41

EEGs produce general data. Brain activity but cannot pinpoint the sources of activity. fMRIs monitor blood oxygenation → active areas require more oxygen → fMRIs can produce 3D images of active areas.

Question 42

What is an ERP?

Answer 42

Measuring the brain’s electrophysical response to specific sensory, cognitive or motor event through statistical analysis of EEG data.

Question 43

Briefly evaluate the use of ERPs as a way of identifying localisation of function in the brain.

Answer 43

Excellent temporal resolution.
Can be used to measure cognitive functions.
Lack of standardisation in research → makes it difficult to confirm findings.
Background noise needs to be completely removed - not always easy to achieve.

Question 44

What is a post-mortem?

Answer 44

An analysis of the brain following death.
Usually people with rare disorders or unusual deficits.
Areas of damage within the brain are examined in order to establish the likely cause of the afflicted the person suffered.
May also involve a comparison with a “neurotypical brain” to ascertain the extent of the different.

Question 45

Outline 1 strength and 1 weakness of post-mortems.

Answer 45

Provided a vital foundation for early understanding of key processes in the brain (eg. Broca and Wernicke’s Area) & Improve medical knowledge.
Causation is an issue - observed damage may not be linked to the deficits under review. Consent is also an issue - patients cannot give it.

Question 46

What is meant by a biological rhythm?

Answer 46

Distinct patterns of changes in body activity that conform to cyclical time periods. Influenced by internal body clocks and external changes to the environment.

Question 47

What is meant by a circadian rhythm? Give an example.

Answer 47

Sleep / wake cycle. A type of biological rhythm subject to a 24-hour cycle.

Question 48

Outline the aim, procedure and findings from Siffre’s cave study.

Answer 48

What would happen if our biological clocks were left to their own devices - would we still wake and sleep at regular times? Siffre spent extended periods of time underground deprived of natural light. In each case his biological rhythm settled down to one that was just beyond 24 hours (around 25 hours).

Question 49

Outline 1 other piece of research into circadian rhythms other than Siffre’s study.

Answer 49

Ashoff & Wever (1976). Ppts in a WWII bunker without natural light. All but one ppt displayed a circadian rhythm of 24-25 hrs. Natural sleep/wake cycle = slightly longer than 24 hours but it is entrained by external factors.

Question 50

Outline 2 practical applications of research into circadian rhythms.

Answer 50

Shift work. Research has shown that night workers are like to experience reduced concentration at around 6am (Boivin et al.). Shift workers are more likely to experience heart disease, possibly due to the stress of adjusting to different sleep patterns & poor quality.
Drug Treatments. Circadian rhythms coordinate basic processes in the body → pharmacokinetics (the action of drugs in the body). Research into circadian rhythms has revealed when drugs are likely to be most effective → Has lead to guidelines of drug dosing and timing.

Question 51

Outline two reasons why the results of research into circadian rhythms lacks generalisability.

Answer 51

Use of case studies and small samples. Siffre - he was over 60 - he noticed that as he got old his circadian rhythm slowed.
Individual Differences. Sleep cycles vary between 13 and 65 hours in some cases (Czeisler et al.). Some people like to go to bed early and rise early (larks) and some do the opposite (owls).

Question 52

What is an infradian rhythm? Give an example.

Answer 52

A type of biological rhythm a frequency of less than one cycle in 24 hours. The menstrual cycle - governed by monthly changes in hormone levels.

Question 53

Outline some research into infradian rhythms.

Answer 53

Stern & McClintock. Took samples of pheromones from women in different stages of the menstrual cycle and passed them onto the other PPTs. 68% experienced changes to their cycle that brought them closer to the odour donor. The menstrual cycle is an endogenous system, but evidence suggests that it may be influenced by external factors.

Question 54

What is seasonal affective disorder?

Answer 54

A form of depression triggered by winter seasons. A particular type of infradian rhythm called circannual rhythms. Possible that melatonin is implicated - during the winter the production of melatonin continues for longer due to the lack of light in the mornings → makes us sleepier.

Question 55

What is an ultradian rhythm? Give an example.

Answer 55

A biological rhythm that occurs more than once in a 24 hour period. The sleep cycle.

Question 56

Explain why the menstrual cycle has been suggested to have an evolutionary basis.

Answer 56

Synchronisation may have an adaptive function because newborns could be cared for collectively. However, this would also produce competition for the fittest males → synchrony avoidance would maybe be better (Schank).

Question 57

Evaluate studies into menstrual synchronisation in terms of methodology.

Answer 57

Many confounding variables were not controlled during studies. Stress, diet, exercise, etc. Typically these studies include small samples of women who self report. Other studies have even failed to find any form of synchrony in all female samples.

Question 58

A lot of information on infradian and ultradian rhythms come from animal studies. Evaluate this.

Answer 58

The fact that we know that animals release pheromones to signal other animals is documented, e.g. sea urchins. Evidence for the effects of in human behaviour remains speculative and inconclusive.

Question 59

Outline what is meant by endogenous pacemakers and exogenous zeitgebers - refer to examples in your answer.

Answer 59

Internal body clocks that regulate our biological rhythms e.g. SCN. External cues that may affect or entrain our biological rhythms e.g. light.

Question 60

Name and describe an endogenous pacemaker.

Answer 60

The suprachiasmatic nucleus (SCN). Tiny bundles of nerve cells located in the hypothalamus → one of the primary endogenous pacemakers. SCN lies above the optic chiasm - receives information about light. Passes this information onto pineal gland which is involved in the production of melatonin.

Question 61

Outline some research into the importance of endogenous on biological rhythms.

Answer 61

DeCoursey et al. Damaged the SCN in chipmunks then released into the wild. Sleep / wake cycle was affected (they didn’t sleep when they were supposed to). Most of them died because they didn’t sleep at the right times.

Question 62

What is an exogenous zeitgeber?

Answer 62

An external cue that may affect or entraine our biological rhythms.

Question 63

Name and describe 2 exogenous zeitgebers.

Answer 63

Light - affects the body’s main endogenous pacemaker (the SCN) & also has an indirect effect on key processes that control such as hormone secretion and blood circulation.
Social Cues - Babies are entrained to have a circadian rhythm → schedules imposed by parents are likely to be important here.

Question 64

Research suggests that peripheral oscillators and other complex influences could act on the sleep / wake cycle. Explain this research.

Answer 64

POs are circadian rhythms within organs and cells. These are affected by the SCN but also act independently. Damiola et al. - alter the circadian rhythm of the liver, whilst leaving the SCN unaffected → other influences on the sleep / wake cycle are possible aside from the master clock.

Question 65

Why has it been suggested that the influence of exogenous zeitgebers on biological rhythms has been exaggerated?

Answer 65

Miles et al. Blind man - circadian rhythm could not be adjusted despite being exposed to social cues. People who live in arctic regions have normal sleeping patterns despite the absence of light.

Question 66

Why is research into internal and external influences often considered as lacking validity? Explain how endogenous pacemakers and exogenous influence the sleep/wake cycle.

Answer 66

Total isolation studies are very rare → lacking validity. Free-running is very rare → in real life the two interact → the SCN controls melatonin + light stimulates the production of melatonin → they work together.

Question 67

What are the ethical issues associated with research into endogenous pacemakers and exogenous zeitgebers?

Answer 67

A lot of studies are done on animals - lacks generalisability. More importantly → harm and risk when returning to natural habitat. They died. Brings about the debate of whether or not what we learn is worth it.