Biopsychology

Question 1

What are the two sections of the nervous system?

Answer 1

• Central (CNS)

- Peripheral (PNS)

Question 2

What does the central nervous system consist of?

Answer 2

Brain & spinal cord

Question 3

What does the peripheral nervous system consist of?

Answer 3

-Somatic, autonomic (sympathetic & parasympathetic).

Question 4

Outline the four main lobes of the brain and there function

Answer 4

• Occipital: processes visual info.
• Temporal: processes auditory info.
• Parietal: integrates info from senses-plays key role in spatial navigation.
• Frontal: higher order functions-planning, abstract reasoning & logic.

Question 5

Outline the role of the brain stem and spinal cord

Answer 5

Brain stem: connects brain stem and spinal cord, controls involuntary processes (heart beat, breathing & consciousness).
Spinal cord: transfers messages to and from brain and rest of body-some simple reflex actions without involvement of brain.

Question 6

Outline the role of the somatic nervous system as part of the PNS

Answer 6

• Facilitates communication between CNS and outside world.
• Made up of sensory receptors-carry info to spinal cord and brain & motor pathways to allow brain to control movement.

Question 7

Outline the role of the autonomic nervous system as part of the PNS

Answer 7

• Important role in homeostasis (maintains internal processes like body temp, heart rate, blood pressure).
• Only consists of motor pathways and has two components (sympathetic and parasympathetic).

Question 8

Outline the role of the sympathetic nervous system as part of the autonomic nervous system

Answer 8

• Involved in responses that prepare body for fight or flight.
• Impulses travel from sympathetic to organs, help prepare for action when faced with dangerous situation (heart rate, blood pressure etc).

Question 9

Outline the role of the parasympathetic nervous system as part of the autonomic nervous system

Answer 9

• Relaxes body, returns us to normal resting state.
• Slows down heart rate, breathing rate, reduces blood pressure- restarts any processes that were previously slowed down (digestion) during fight or flight.

Question 10

Outline some similarities and differences between the CNS & PNS

Answer 10

Similarities: Brain stem and spinal cord both control involuntary processes (breathing & reflexes).
Differences: Brain provides conscious awareness-allows for higher-order thinking-spinal cord allows for simple reflexes.
-Brain consists of multiple regions for different functions, spinal cord has one main function.

Question 11

Outline the role of a relay neuron

Answer 11

• Found between sensory input and motor output/response.

- Found in brain and spinal cord-allow sensory and motor neurons and motor neurons to communicate.

Question 12

Outline the role of motor neurons

Answer 12

• Found in CNS.
• Control muscle movements.
• When stimulated, release neurotransmitters that bind to receptors on muscles to trigger response, leads to movement.

Question 13

Outline the role of each part of part of a neuron

Answer 13

• Dendrites: receive signals from other neurons or sensory receptor cells. Typically connected to cell body.
• Cell body: often referred to as the ‘control centre’-contains nucleus.
• Axon: long slender fibre, carries nerve impulses in form of electrical impulses (action potential), away from cell body towards axon terminals where neuron ends.
• Myelin sheath: Insulates axon so electrical impulses travel faster along axon.
• Axon terminal: connects neuron to other neurons (or directly to organs)- using synaptic transmission.
• Nodes of ranvier: speed up electrical impulses by making them ‘jump’ gaps.

Question 14

Outline the process of synaptic transmission

Answer 14

Presynaptic neuron:
1. When neuron activated, becomes + charged for split second.
2. Sends elec impulse down axon, jumping nodes of ranvier, to terminal buttons.
3. Impulse triggers neurotransmitters (both excitatory/inhibitory) in vesicles to move to pre-synaptic membrane where it fuses/releases neurotransmitters into synaptic gap.
Post-synaptic neuron:
4. If neurotransmitter comp fits receptors dendrites of post synaptic neuron, taken up (lock and key).
5. When enough receptors taken up, chemical message converted into electrical impulse.

Question 15

Outline the two different types of neurotransmitter and how they effect synaptic transmission

Answer 15

Excitatory: makes post-synaptic neuron more likely to fire. If binds to post-synaptic receptors-causes electrical charge in cell membrane=excitatory post synaptic potential (EPSP).
Inhibitory: makes post-synaptic neuron more likely to fire-if binds to post-synaptic receptors-results in inhibitory post-synaptic potential (IPSP.

Question 16

Outline summation

Answer 16

If neuron receives both-has to add up inputs.

• Spatial: Many EPSPs generated from many diff neurons at same time.
• Temporal: EPSPs generated in series of high-frequent action potentials.

Question 17

Outline and evaluate the fight or flight response for an unconscious, acute stressor

Answer 17

Amygdala activated and sends distress signal to hypothalamus:

1. Hypothalamus activates sympathomedullary pathway running to adrenal medulla and sympathetic NS.
2. SNS stimulates adrenal medulla.
3. Adrenal medulla secretes hormone adrenaline and noradrenaline into blood stream.
4. Adrenanile causes number of physiological changes to prepare body for fight or flight (increase heart rate etc.).

A03:

• Leads to CHD-bad for heart.
• Individual effects>girls tend/befriend as fleeing may put offspring in danger- beta bias-research typically conducted on males-assumed findings could be generalised to females- until Taylor provided evidence of tend/befriend.

Question 18

Outline the fight or flight response for an ongoing stressor, chronic

Answer 18

HPA axis:

1. Hypothal sends CRF to pituitary gland.
2. Pituitary gland sends ACTH in blood to adrenal cortex.
3. Adrenal cortex releases long term energy via hormones (e.g. cortisol).

A03:

• Cortisol decreases white blood cell, increasing vulnerability to illness-maladaptive response to modern-day life.
• Outdated> no longer need to fight/flight.
• Not explain everything>sometimes freeze (Gray- first response to danger is to avoid confrontation altogether)- appraise situation, decide best course of action.

Question 19

Outline the endocrine system

Answer 19

• Network of glands that secrete hormones (chemical messages) via blood stream, making it slower than Ns.
• Can cause physiological changes (e.g. growth).
• Hormones secreted by glands only affect specific target cells (with right receptors).
• Too much hormone=bad (cortisol related to depression). Excess release of hormones causal by tumours on pituitary gland causing increase release of ACTH> causal adrenal gland to secrete too much cortisol.

Question 20

Outline the role of the pituitary gland as part of the endocrine system

Answer 20

• Master gland- hormones released by pituitary gland control and stimulate release of hormones from other glands in endocrine system.
• Main hormone released is melatonin-responsible for important biological rhythms-sleep wake cycle.
• Posterior: releases ACTH.
• Anterior: releases oxytocin-responsible for uterus contractions during childbirth.
• Hypothalamus connected pituitary gland-responsible for stimulating/controlling release of hormones from pituitary gland.

Question 21

Outline localisation of function

Answer 21

• Certain functions have certain locations or areas within the brain.
• Used to be studied using techniques like post mortem but now using brain scanning technology.

Question 22

Outline hemispheric lateralisation as part of localisation of function

Answer 22

• Dominance of one hemisphere of the brain for particular functions.
• Activity is contralateral-left-had side of body controlled by right-hemisphere and visa versa.
• Left side of brain contains language areas.
• Left and right hemispheres connected by bundle of fibres-corpus collosum.

Question 23

Outline the motor area of the brain as part of localisation of function

Answer 23

• Located in the frontal lobe.

- Responsible for voluntary movements-sends signals to muscles in body.

Question 24

Outline the somatosensory area of the brain as part of localisation of function

Answer 24

• Located in parietal lobe.

- Receives incoming sensory info from skin to produce sensations related to pressure, pain, temp.

Question 25

Outline the visual area of the brain as part of localisation of function

Answer 25

• In occipital lobe.
• Receives and processes visual info.
• Info from right-hand side visual field processes by left hemisphere, info from left hand side visual field processes by right hemisphere.
• Contains different parts that process different types of info incl. colour, shape or movement.

Question 26

Outline the auditory area of the brain as part of localisation of function

Answer 26

• Located in temporal lobe.
• Analyses/processes acoustic info.
• Info from left ear goes primarily to right hemisphere and info from right ear goes primarily to left hemisphere.
• Contains different parts, primary auditory area involved in processing simple features of sound, incl. volume, tempo, pitch.

Question 27

Outline Broca’s area as part of localisation of function

Answer 27

• Discovered while treating patient Tan.
• Tan could understand spoken language but was unable to produce any coherent words, and could only say ‘tan’.
• After Tan’s death, Broca conducted a post-mortem on tans brain-discovered he had a lesion in the left frontal lobe-led broca to conclude that this area was responsible for speech production.

Question 28

Outline Wernicke’s area as part of localisation of function

Answer 28

• Involved in understanding language.
• Wernicke found patients with lesions to Wernicke’s area were still able to speak, but unable to comprehend language.
• Posterior portion of left temporal lobe-thought to be involved in language processing/comprehension.

Question 29

Evaluate localisation of function

Answer 29

Strengths:

• Support for aphasia: Damage to broca/wernickes area causes diff types of aphasia- Expressive aphasia (Broca), Receptive aphasia (wernickes).
• Support from brain studies: Peterson used brain studies to determine how wernick’es area active during listening task/broca’s during reading one-highly controlled etc.

Weaknesses:

• Individual differences: Baveler-differences in patterns of activation between pps-some active in right temporal lobe, left frontal lobe and occipital lobe (non of which normally active).
• Too simple: Lashley thought brain able to reorganise itself (plasticity)-healthy brain areas can take on responsibility for function of damaged area-diff areas of brain can adapt to do different function-rather than certain areas being designed to conduct specific function.

Question 30

Outline split brain research as evidence for hemispheric lateralisation

Answer 30

Treatment for severe epilepsy- cut corpus collosum so epileptic seizure couldn’t cross hemispheres.

Sperry: Pps severe epilepsy patients (split hems).
-Looked at dot directly infront.
-If shown dog in right visual field (left hem), verbal response= dog. Drawn response= nothing.
-If shown cat in left visual field (right hem), verbal response= nothing. Drawn response= cat.
Right hemisphere can process picture pf cat but cannot respond verbally- left hemisphere (could respond, doesn’t see cat).

Question 31

Evaluate hemispheric lateralisation

Answer 31

Strengths:
-Support from chickens: Rogers found chickens require lateralisation to carry out two tasks-finding food and being vigilant for predators.
-Controlled procedures: Sperry used standardised procedures- flashed images extremely quickly to control hem that received image- easily repeated etc.
Weaknesses:
-Small sample: only 11 pps- each with different levels of disconnection, BUT 11 pps made up large % of total pop suffering severe epilepsy-high pop validity.
-Language not only on left: J.W. developed capacity to speak out of right hem, with result that he can now speak about info presented to left or right brain- Turk et al.

Question 32

Outline plasticity

Supporting evidence

Answer 32

-Brains tendency to change/adapt as result of experience/new learning.
Video games: Kuhn-compared control group with ‘video game training group’ that played super Mario cart for 30 mins a day for 2 months- significant increase in grey matter in various brain areas- cortex, hippocampus.
Meditation: Lazar- MRI scans show meditators have thicker cortex- 8 week course showed more grey matter in hippocampus (learning, memory).
Maguire: London taxi drivers- increased grey matter in posterior hippocampus- involved in development of spatial and navigational skills- significant correlation between side of posterior hippocampal volume and length of time spent as taxi driver.

Question 33

Evaluate plasticity

Answer 33

Strengths:

• Controlled procedures: scientific controlled measurements (MRI).
• Support from rats: increased number of neurons in brains of rats housed in complex environments compared to rats housed in lab cages.
• Support from human research: Draganski- imaged medical students brains before and after exams-learning induced changes seen in posterior hippo.

Weaknesses:
-Can’t be sure difference in Maguire’s study due to ‘knowledge’-weren’t tested before-may already had spatial awareness skills.

Question 34

Outline functional recovery
Research support?
Ways the brain does this?

Answer 34

• The recovery of abilities and mental processes
• EB suffered lost language abilities (left hem)- after rehab language fluency improved.

1. Stem cells: replace dead/decaying cells, rescue dying cells, link undamaged brain areas.
2. Neural unmasking: we have ‘dominant synapses’-when surrounding areas damaged-rate input increases- causing dormant synaptic paths to ‘unmask’ (open).

Question 35

Evaluate functional recovery

Answer 35

Strengths:
-Tajiri- rats with stem cells developed neuron-like cells in area of injury.
-Support for neural unmasking- Axon sprouting: new nerve endings, grow connect undamaged areas. Reformation of blood vessels, recruitment of similar areas on opp hems.
Weaknesses:
-Reliance on animal studies.
-Decreases with age: although studies shown abilities commonly fixed in childhood, still modified in adults with intense training.

Question 36

Outline and evaluate most mortems as a way to study the brain

Answer 36

-Post mortem: identifies underlying neurobiology of partic behaviour- physical observation. e.g. Tan.

+Vital during early days of psych before other tech developed.
+Allows for more detail than non-invasive methods-study of deeper brain regions.
-Cause/effect problem- differences observed in dead brain may not have caused earlier behaviours-many confounding variables- time etc.
-Retrospective: cannot see when activated.
-No Informed consent.

Question 37

Outline and evaluate FMRI as a way to study the brain

Answer 37

-FMRI: measures energy released by haemoglobin using radiowaves. More active brain area= more o2/blood flow- produces dynamic picture.

+Moving picture-patterns can be compared.
+High res images- clear where functions localised.
+No radioactive tracer (like PET), risk free, non invasive.
-Expensive, requires expensive equipment, trained experts etc.
-Indirect: studies blood flow, not actual firing of neurons- 5sec delay between neuron firing and activity detecting-not real time.

Question 38

Outline and evaluate EEGs as a way to study the brain

Answer 38

-Electrodes placed on scalp, detect/measure changes in electrical activity caused by neurons.

+Real time, no delay.
+More widely available.
-Can only detect superficial (outside regions)-cannot reveal activity of deeper regions.

Question 39

Outline and evaluate Infradian rhythms

Examples (SAD, menstrual cycle)

Answer 39

-Over 24hrs, occur weakly, monthly or annually. 
SAD- occurs annually- longer nights, pineal gland produces more melatonin-requires serotonin-low levels linked with depression.
Menstrual cycle (monthly): Oestrogen-promotes ovulation, once follicle ripened-releases progesterone-lining of womb prepares for implantation of egg- increasing blood supply- if no preg after 2 weeks, progesterone reduced-lining of womb shreds.

+RLA: light boxes for SAD- phototherapy-resets melatonin levels.

• Light also effects menstruation: Reinberg- women lived in cave 3 months, exposed to dim light- sleep wake cycle changed, menstrual cycle shortened.
• Menstruation affects mating: women prefer ‘feminised’ males for long term, but ‘masculine’ during ovulation- want men with good genes.

Question 40

Outline and evaluate ultradian rhythms

Examples (BRAC, sleep stages)

Answer 40

-More than once in 24hrs.
BRAC (timing): Kleitman- BRAC=90min cycle when awake- we move progressively from state of alertness into psychological fatigue.
Sleep stages: 90-100mins throughout night- 1-2: Light sleep (brain waves slow, alpha/theta). 3-4: Deep sleep (Delta occur, little eye movement). 5: REM (brain/eyes active).

+Support: Dement & Kleitman- REM highly correlated with experiencing dreaming, eye movement corresponded to dream content.
+Objective measures: EEG, EOG- advanced understanding.
-Low eco validity-lab studies- not measuring real sleep.
-Individual differences in sleep may be biologically determined.

Question 41

Outline and evaluate circadian rhythms

Examples (Siffre, SCN/melatonin)

Answer 41

• Every 24hrs.
• SCN-keeps sleep/wake cycle constant-monitors light coming through eyes (SCN picks up signal from optic chiasm) If detected, SCN sends message to pineal gland to produce more melatonin (sleep). 2 peaks in day when we want to sleep (2am/1-3pm). Light=primary input to SCN, setting body to correct time- photo entrainment.
• Homeostatic control: also regulates SCW- If tired, homeostasis tells us we need sleep-used energy, need to regain it.
• Siffre: free runner- no stimuli to guide rhythm- acts as support for end/exog as when younger- circ rhythm-roughly same time, when older rhythm out of control-48hrs.
• Core body temp cycle: temps fluc during circ rhythm- lowest=4:30 am (lowest energy), highest=6pm.

+RLA: chronotherapeutic- timing effects drug treatment- essential right amount of drug released at right point during rhythm.
+Folkhard/core temp: link between temp change in day & cog ability of teenagers: 9am=poor recall/comprehension, 3pm=good recall.
-Siffre only case study
-Indi diff: Cycle length (13-65hrs), cycle onset (where cycles reach peak).

Question 42

Outline and evaluate endogenous/exogenous

SCN, melatonin, light, social cues

Answer 42

Endogenous: internal mech:
-SCN rhythm= endog (affected by light)- 1. CLOCK/BMAL 1 produced-bind together. 2. Produce PER/CRY-make BMAL inactive- less PER/CRY- neg feedback loop.
-Melatonin release: Pineal gland/SCN linked- SCN regulates pin gland to secrete melatonin-promotes sleep-inhibits brain mech that promote wakefulness.
Exogenous:
-Light: SCN obtains light even when closed- rods/cones detect in retina- transfers info to receptors in SCN- synchronises body activity.
-Social cues: influenced by norms of people around us- compensate for not knowing time of day by using social cues.

+Support for light from Siffre- but case study.
+Support for role of social cues and light: jet lag studies- circadian Rs adjust quicker when travellers went outside more at destinations- social cues acting.
-Social cues less effective than light: blind mans sleep cycle couldn’t be adjusted despite social cues.