biopsychology Flashcards

Question

evaluate plasticity and functional recovery

Answer 1

-negative plasticity may have negative behavioural consequences Medina (2007)- brain's adaption to prolonged drug use leads to poorer cognitive function later in life 60-80% of amputees have phantom limb syndrome, Hirstein (1998) painful sensations due to cortical reactions in the somatosensory cortex +plasticity may be lifelong Bezzola (2012)- 40hrs gold training produced change in neural representation of movement in participants age 40-60 using fMRI, shown decreased motor cortex activity in novice golfers- suggesting more efficient representations after training, showing neuroplasticity can continue throughout lifespan +RWA understanding processes has contributed to neurorehabilitation e.g understanding axonal growth meant new therapies that had never been tried before were e.g after a stroke, constraint-induced movement

Answer 2

fMRI detects changes in blood oxygenation and flow when an area is active, more oxygen is used- haemodynamic response EEG measures electrical activity using electrodes ERPs measures types of brainwaves which are triggered by particular events post mortem examination analysis of brain after death

Answer 3

fMRI +no radiation +non-invasive +high spatial resolution -expensive -poor temporal resolution (5s time lag) EEG +high temporal resolution +RWA, sleep, epilepsy -generalised nature, doesn't pinpoint exact source of activity ERPs +more specific to measurement of neural processes -lacks standardisation -extraneous material has to be removed post mortem +_provided foundational understanding of brain's structure -ethical issues -0difficult to establish accurate causation

Answer 4

lateralisation is the idea that the two hemispheres are functionally different and certain processes are controlled by each hemisphere e.g: left side of brain responsible for language tasks, right side for spatial/face recognition tasks Split-brain research - patients had corpus callosotomy (corpus callum is severed so hemispheres are separated) to help with epileptic fits -Sperry (1968) compared patients with connected and split brains using visual and tactile tasks describe what they see: if shown to left visual field, couldn't describe it (goes to RH which isn't responsible for language) recognition by touch: object in each hand, lose it and find it again - can find object but only with original hand (e.g, left hand sends message to RH, the RH then controls the left hand to find the same object again) drawings: consistently better when drawn with left hand (controlled by RH which does spatial tasks) face recognition: shown picture that's half man, half woman right eye> message to LH> say man left eye> message to RH> find other half of woman

Answer 5

+supporting evidence for lateralisation Fink (1966)- used brain scans to identify which brain areas were active during a visual processing task. participants with connected brains asked to look at global elements of an image, RH more active, but when asked to look at specific elements, LH dominated suggests hemispheric lateralisation is a feature of split-brain and connected brain people. -issues with generalisation researchers urge caution is accepting these findings difficult to generalise when research groups are so small - e.g in Sperry's study, only 11 people took part in all variations, all had experienced epileptic seizures and had different levels of disconnection -differences in function may be overstated pop-psychological literature over-emphasises and oversimplifies the functional distinction between LH and RH 'verbal' and non-verbal' labels are contended by modern neuroscientists who argue the distinction is far too clear cut in the connected brain, the two hemispheres are in constant communication and behaviours typically associated in one hemisphere can often be performed in the other hemisphere.

Answer 6

a circadian rhythm is a biological rhythm that has a cycle length of roughly 24 hours. The sleep-wake cycle is an example of a circadian rhythm. It dictates when we should be awake/asleep, with light and darkness helping determine when the cycle occurs. The internal 'clock' is 'free running', and it will maintain a cycle of 24-25 hours even in the ABSENCE OF EXTERNAL CUES. the sleep wake cycle can be represented on a graph of alertness. You are the most alert around 6pm-9pm, closely followed by 9am. The body experiences dips after midday and around 6am. Siffre did a field experiment by staying in caves and studying his own circadian rhythms. no external cues, only thing influencing his behaviour was internal body clock. study 1 ------ 61 days in Alps in 1962. study 2------ 6 months, established body clock was 24 hrs study 3------ body clock ticked more slowly to when he was younger, sometimes stretching his circadian rhythm to 48 hours.

Answer 7

+support from other research Aschoff and Wever (1976)- group of participants spent a week in WW2 bunker, deprived of natural light. all but one had a circadian rhythm of 24-25 hours. +shift work provides an understanding of the consequences that occur when circadian rhythm is disrupted- desynchronisation. e.g: night workers experience decreased concentration at 6 in the morning, meaning accidents more likely- Boirin (1996) Knuttson (2003), relationship between poor health and shift work- 3x more likely to develop heart disease -individual differences genralisations difficult to make studies based on small samples sleep-wake cycle varies from person to person Czeisler (1999)- cycles vary from 16-65 hours difficult to use data to discuss anything other than averages, which may be meaningless

Answer 8

voluntary movements, connects the CNS and the senses

Answer 9

towards the brain

Answer 10

endogenous pacemaker: -internal body clocks -main one is SCN which is group of cells found in hypothalamus, linked via neural pathway to pineal gland (melatonin production) low light>optic chasm in eye>stimulates SCN>stimulates pineal gland>produces melatonin>brain activity falls (sleep) exogenous zeitgebers: -outside time givers -biological clock needs to be reset to allow organisms to adjust to changing daylight in seasons- this is done via environmental cues light cues- sunrise/sunset- affects hormones and blood circulation social cues- research on jet lag shows adjusting to local time (not following body cues) on when to eat/sleep is an effective way of entraining circadian rhythm. entrainment is- alignment of our internal body clocks with the external environment.

Answer 11

+animal studies demonstrated the importance of SCN Morgan (1995) bred hamsters with abnormal circadian rhythms of 24 hours. Transferred their SCN neurons to healthy hamsters, which they displayed the same abnormal circadian rhythm. +power of light light is a powerful exogenous zeitgeber Campbell and Murphy- light may be detected by receptors on skin 25 participants were woken at various times and a light was shone on back of their knees. In some cases, managed to shift circadian rhythm by 3 hours. Supports importance of light, even suggesting it need not necessarily rely on eyes to exert influence over the brain. -other exogenous zeitgebers overexaggerated Miles (1977)- recount story of blind man who had an abnormal circadian rhythm of 24.9 hours. Despite exposure to social cues (regular mealtimes) his sleep wake cycle could not be adjusted to 24 hours. Suggests there may be occasions certain exogenous zeitgebers have little bearing on our internal rhythm.

Answer 12

INFRADIAN *menstrual cycle* oestrogen rises>ovary develops egg and releases it (ovulation) > progesterone rises> womb lining grows thicker> if no pregnancy, comes away from body and egg absorbed by body. cycle typically 28 days endogenous cycle , but Stern and McClintock demonstrated it may be affected by exogenous factors. had 29 women , took samples of pheromones from 9 women. 20 had this cotton pad rubbed on their lip. 68% experienced cycle change which brought them closer to the cycle of their 'odour donor' * seasonal affective disorder (SAD) * depressive disorder which has a seasonal pattern, triggered by fewer daylight hours which disrupts sleep/wake cycle- melatonin continues to be produced, which causes serotonin to be produced too (this is associated with depressive symptoms) circannual rhythm- subject to yearly cycle. ULTRADIAN *sleep stages* stage 1 - alpha waves/high frequency/short amplitude/easily woken stage 2- alpha waves and occasional sleep spindles stage 3+4 - delta waves/slow wave sleep (SWS)/lower frequency/higher amplitude stage 5- body paralysed/brain activity as though awake/ theta waves/REM (dreams likely)

Answer 13

EVOLUTIONARY VALUE if menstruate at same time, fall pregnant at same time, raise babies collectively. EXTRA: However, would also mean more competition for highest quality males so may be advantageous to avoid synchrony. SLEEP STAGES Dement and Kleitmen (1957)- studied 9 adults in sleep lab using EEGs to measure brainwaves. Caffeine and alcohol effects controlled REM activity correlated with dreaming participants were woken during dreaming and could report dreams vividly. practical application light therapy> resets body's internal clock Sanassi (2014)- helped 80% with SAD symptoms preferred to antidepressants as it's deemed safe EXTRA: Rohen (2009)- relapse rate of light therapy is 46% compared to 27% of those receiving CBT

biopsychology Flashcards

(37 cards)