Biopsychology Flashcards

Question

Lateralisation in the left hemisphere

Answer 1

* Receives info from right visual field * Controls right side of the body * Performs tasks like logic, language and reasoning

Answer 2

* Recieves info from left visual field * Controls left side of the body * Performs spatial tasks, art, music

Answer 3

11 patients, quasi experiment, screen, flashing image Task- name what you see (language test) or draw what you see (visuo-spatial test)

Answer 4

Left hemisphere- analytic and verbal tasks Right hemisphere- Spatial tasks and music However the fact all ptts had severe epilepsy may suggest they became more lateralised than the general population

Answer 5

-Age: we become less lateralised as we age (Szaflarski et al 2006)- Lang becomes more lateralised to LH w increasing age when we are children & adolescents but when we reach 25 yrs lateralisation decreases w every decade of life. Raises Qs about whether everyone has a hem that's more dominant. +/- Sperry's work: Well controlled standardised procedures, impressive findings, however he used a small sample size of 11 patients who all had severe epilepsy so may make difficult to generalise. -Case studies such as JW (who learned to speak out of his right hemisphere) shows that language can be processed in right hem which contradicts the idea that language is processed in left hem. -Duality theory (idea of 2 seperate brains) is oversimplified: in reality the differences between right and left hem are more intricate than lateralisation suggests.

Answer 6

Circadian rhythm- 24 hrs (e.g. sleep/wake cycle) Infradian rhythm- period longer than 24hrs (e.g. menstrual cycle, SAD) Ultradian rhythm- occurs more than once in 24hrs (e.g. sleep cycle)

Answer 7

Stage 1- theta waves appear,feel as if falling breathing and HR and temp fall slows. Stage 2- sleep spindles (sudden bursts activity) and K-Complexes (suppressing outside stimuli). Stage 3 & 4- deep sleep, delta waves, gradually become unresponsive,confused if woken, sleep walk & talk, bedwetting, no eye movement, the lowest point for HR, BP and temp. Stage 5- REM (rapid eye mov), sleep paralysis,beta waves resembeling awake state, HR & BP fluctuate, dreaming occurs.

Answer 8

* Typically 28 days * Controlled by Pituitary gland receiving info from hypothalamus * Ovulation occurs as oestrogen rises * Progesterone helps womb lining grow thicker * If pregnancy doesn't occur egg is absorbed and womb lining leaves body

Answer 9

* Seasonal affective disorder 'winter blues' * Pineal gland secretes melatonin until dawn (there is more light) * Lack of morning light in Winter means melatonin secretion lasts longer making us more tired. * Has knock on effect of melatonin production in the brain

Answer 10

* Time makers * Synchronised by the master clock: Suprachiasmatic nuclei (SCN) found in hypothalamus. * SCN constantly reset by light levels and tells pineal gland to produce melatonin to induce sleep.

Answer 11

* External factors (time givers) * Help rest endogenous pacemakers * Light primary input into system- setting body clock to correct time * Entrainment can occur when we move across zones * Other EZs (e.g. regular meal/bath times

Answer 12

* He spent extended periods underground to study effects on his own bio rhythm * He had no exposure to natural light and was sound deprived * He had access to adequate food and drink * Did 2 months underground in a cave in the alps and 6 months in a Texan cave * He discovered that his biological clock settled down to a **25hr clock**

Answer 13

* Convinced group of ptts to spend 4 weeks in WW2 bunker * All ptts kept a circadian rhythm between 24-25 hrs apart from 1 ptt (29hrs) * Suggests natural sleep/wake cycle is slightly longer than 24hrs but is entrained by exogonous zeitgebers.

Answer 14

* Ptts lived in a cave and apparant 24hrs turned into 22hrs * Only 1 ptt was able to adjust * Represents we have internal mechanisms that can't be easily overriden

Answer 15

* Collected sweat from one woman (donor) * Wiped under noses of female ptts * In 68% of cases changes seen in womens menstural cycle as they became closer to donor * This occurs as pheromone molecules dissolve inside the nose, stimulate neurones, affecting hypothalamus which alters pattern of hormone production.

Answer 16

* looked at EEG readings * Made sure exp controlled for effects of caffine and alchol * Found REM sleep to be highly correlated with dreaming * the more vivid the dream, the more active the brain * If woken during REM stage ppl could easily recall their dreams

Answer 17

+RWA: shift work (lose concentration at 6am), jet lag (Burgess=exposure to light). +Research support: Sifffre's cave study that our sleep/wake cycle settles down between 24-25 hours and that exogenous zeitgebers help keed it to a 24hr rhythm. -Individual differences:

Answer 18

Following injury/trauma (e.g.stroke) unaffected areas of brain compensate and adapt.

Answer 19

*** Synaptic reweighting**- If activity increases more neurotransmitters released and stronger signal. *** Creation of new synapses**- If axon of one nerve cell passes close to dendrite of another then a new synapse is formed. *** Synaptic pruning**- deleting synapses that are not used, 'use it or lose it'.

Answer 20

*** Neuronal unmasking**- Dormant neurones unmasked that are close to area of damage. *** Axonal sprouting**- Undamaged axons physically grow new nerve endings and hook onto dendrites of other neurones and form new synapses. *** Recruitment of homologous areas**- Mirror neurones on opposite side of brain gradually take over lost functions.

Answer 21

**Maguire research on taxi drivers:** Changes in brain detected as a result of extensive experience of spatial navigation. MRI discovered had greater posterior hippocampi. **Boyke et al study on 60yr olds learning to juggle:** Increase in grey matter (neurones) in visual cortex, however changes reversed when practise stopped.

Answer 22

**Danielli et al, case study of EB**- 2 and half yr old Italian boy. Virtually all of LH removed meaning his linguistic abilities disappeared. At 5 after rehab there were no major problems in his linguistic ability, by 17 his RH had fully compensated. **Takatsuru et al**- If undamaged area stimulated soon after stroke then recovery can be improved.