Bloa Flashcards

Aim: to investigate whether genetics had an effect of bulimia nervosa in families

Method: over 2K sets of female twins identified a number of risk factors in bulimia (birth after 1960, history of wide weight fluctuations, low paternal care, external locus of control)

Results: concordance rates of 23% in MZ twins, 9% in DZ; in all studies, concordance rates in MZ>DZ, but varied 23-83%

Conclusion: genetics may have an effect on people getting bulimia, self-reporting data not reliable

Aim: to prove that learned helplessness can lead to depression

Method: a dog was trapped in an enclosed area where the floor was lined w/ electrodes; experimenter would activate electrode once in a while & dog would jump over low wall to other side of enclosed area where no electrodes were. experimenter raised wall slowly until too high for dog to jump over; after a few trials, the experimenter lowered the wall again

Results: dog gave high wall a few attempts, but after knowing it was too high gave up & let self get electrocuted; when lowered, didn't attempt to jump across

Conclusion: dog learned incapable of jumping across; learned helplessness=lowered self esteem

Aim: to investigate how sensory deprivation affects the brain

Method: group of monks taking 72-hr pilgrimage to a mountain who weren't allowed to speak, eat, or drink; exposed to cold late autumn weather. after 48 hrs, started seeing hallucinations of ancestors & feeling their presence

Results: blood samples taken before/after pilgrimage; found increased levels of serotonin in brains (hypothalamus/frontal cortex), resulting in hallucination

Conclusion: sensory deprivation triggered the release of serotonin (sleep/arousal/emotion)

Aim: to investigate behavioral, psychological, neurological consequences when the R/L hemisphere of the brain is disconnected

Method: subjects were patients who had disconnection surgery to stop epileptic seizure; given series of tests:

1. visual info presented to L/R side of brain

2. present tactile stimulus to L/R side, screen used to cover/remove visual identification

Results: object shown on L side will only be recog'd when shown on L side; only objects shown to R visual field can be named verbally/written down; if felt by L hand, only recog'd by L hand again

Conclusion: brain function is localized; speech/writing comprehension happens in L hemisphere; processing of image/visuals happen in RH; different visual perception/memory storage in each hemisphere

Description: HM was involved in a traumatic bike accident at age 7 which caused brain damage and at age 10 began experiencing seizures. By age 27, they were so incapacitating he couldn't function normally and meds were ineffective. In 1953, he underwent an experimental procedure to alleviate severe epilepsy; decision made to surgically remove medial temporal lobe structures (hippocampus). Surgery succeeded in alleviating seizures, recovered w/out complications; only side effect was development of anterograde amnesia (loss of ability to form new memories)

Method: researchers described results of testing HM/9 other patients who had been treated for psychosis using similar neurological methods

Results: anterograde amnesia, still had motor/procedural memory; connection between cognition/biology

Description: Famous British pianist/conductor, Clive Wearing, contracted virus that caused him to experience anter/retrograde amnesia, meaning memory only lasts 7-30 secs before it 'resets'. MRI scans of brain show damage to hippocampus/frontal regions; has semantic/procedural memory, not episodic. Remembers things like: speech, wife, walk, eat, children, read, piano but NOT: past, what food tastes like

Conclusion: case studies are helpful/used; connections between physical rain & mental/biological processes

Aim: to study the role of oxytocin following breaches of trust

Method: 49 participants placed in fMRI scanner, receiving either OT/placebo via nasal spray; told to act as investors in several rounds of a trust game w/ different trustees; also to engage in risk game against a computer. received feedback from experimenters- divided into pre/post-FB phase, FB in between, indicated that 50% of decisions resulted in poor investment b/c trust broken

Results: placebo more likely to decrease rate of trust after trust broken; OT cont'd to invest at similar rates (didn't matter); different brain areas active in 2 groups (amygdala, caudate nucleus)

Conclusion: OT may have role in lowering fear reactions, facilitating expression of trust, ignoring negative FB

Aim: to investigate whether high levels of stress hormone cortisol interfere w/ verbal declarative memory

Method: students @ WashU Med. Center given clinical interview w/ physician; designed experiment w/ 3 conditions:

C1: high cortisol-- tablet w/ 160 mg cortisol for each of 4 days

C2: low cortisol-- tablet w/ 40 mg cortisol per day

C3: control/placebo group-- placebo tablets

All asked to listen/recall parts of prose paragraph, testing verbal declarative memory, often affected during long-term stress; assigned in match-pair design, under double-blind control

Results: high cortisol levels impaired performance in memory task, though effect not permanent (back to normal after tablets stopped)

Conclusion: results demonstrate clear link b/n levels of cortisol & remembering; errors tended to be of omission not commission (impairment of recall)

Aim: to determine the role of acetylcholine on memory

Method: rats trained to go through a maze to get to food at end; once familiar w/ route, injected:

1. w/ scopolamine (less ACH)

2. w/ physostigmine (more ACH)

3. control (normal ACH)

Results: 1st group slowest at finding way w/out errors; 2nd fastest w/ least mistakes; 3rd group average

Conclusion: ACH plays role in creating memory of maze; cells=Alzheimer's?

Aim: to investigate whether environmental factors (rich/impoverish environment) would affect development of neurons in cerebral cortex

Method: rats placed in EC/IC;

EC-- placed 10-12 rats in cage w/ different stimuli to explore/play, received maze training

IC-- each rat in individual cage, lacking toys/maze (+SC w/ food/water)

spent 30-60 days in respective environment, killed to study changes in brain's anatomy

Results: anatomy of brain was DIFFERENT! increased thickness/higher weight of EC cortex; rats in EC had developed significantly greater activity in neurons of cerebral cortex (ACH transmission)

Conclusion: human brain should be affected by environmental factors (i.e. intellectual/social stimulation, poverty)

Aim: to investigate the function of the hippocampus in spacial memory

Method: 16 mentally/physically healthy, R-handed male taxi drivers ages 32-62 + 50 healthy R-handed control males scanned w/ same MRI machine; amount/density of grey matter in hippocampus counted

Results: taxi drivers have significantly larger hippocampus; volume of hippocampus correlates w/ amount of time as TD

Conclusion: MRI can be used to detect active areas of brain; environment's effects on enuroplasticity

Aim: to investigate the role of genetics on sexual orientation

Method: recruited MZ/DZ twins + adoptive brothers through gay publications; all of sample voluntary/male, raised together (environment similar); sexual orientation of relative assessed by asking directly/asking participant; used questionnaire to assess level of childhood gender non-conformity

Results: 52% of MZ twins both self-ID'd homosexuals; 22% DZ; 11% non-related; 9.2% non-twin; the more closely genetically linked a pair is, the more likely they are to exhibit gay/straight tendencies; participants' self-reported history didn't predict homosexuality

Conclusion: support for a genetic link for homosexual behavior

Aim: to determine how much of intelligence is attributed to genetics/the environment

Method: longitudinal study on over 100 sets of MZ/DZ twins from around the world who were raised together & reared apart; researchers administered approx. 50 hrs of psychological/physiological testing

Results: similarity rates b/n MZ reared apart=76%; determined heritability estimate of 70% of intelligence to genetics, 30% to other factors

Conclusion: concordance rate b/n twins shows behavior mostly affected by genetics, 30% by environment

Background: in first trimester of pregnancy, hormones lower women's immune systems so that don't fight foreign new genetic material in womb; emotion of disgust allowed our ancestors to survive long enough to produce offspring/pass sensitivities to us

Aim: to investigate whether disgust helps to compensate for the suppressed immune system

Method: 496 healthy pregnant women ages 18-50 asked to rank 32 potentially disgusting scenarios (asked if experiencing morning sickness also)

Results: women in 1st trimester scored higher in disgust sensitivity than women in 2nd/3rd trimesters; when controlled for morning sickness, response only applied to scenes w/ food

Conclusion: explained in terms of large extent of dangerous food-borne diseases; natural selection may have helped human ancestors be pickier w/ food to compensate for higher susceptibility to disease

Aim: to see if simply looking at the emotion expressed on someone's face would cause the brain of the observer to be stimulated

Method: asked participants to look at various human faces (pictures) while undergoing an fMRI; participants had to imitate the faces shown and then they watched as the faces were shown again

Results: not only were the same areas of the brain activated in both cases, but it became clear that the limbic system was also stimulated - observing a happy face activated pleasure centers in the brain

Aim: to discover (using PET scans) if murderers who pleaded not guilty by reason of insanity (NGRI) show evidence of brain abnormalities.

Method: 41 participants (39M, 2F) and 41 controls, selected based on sex, age and matched to a NGRI participant; each participant injected with glucose tracer (bonds to glucose) (for PET scans) that tracks brain activity as the brain absorbs glucose; radioactive glucose tracer emits positively charged particles called positrons, which are picked up by the scan; they had to perform tasks requiring them to detect target signals for 32 minutes

Results: NGRIs had less activity in pre-frontal cortex; linked to self-control and emotion; NGRIs had lower activity in the amygdala and medial temporal hippocampusLack of inhibition of violent behaviour; Fearlessness - Inappropriate emotional expression, failure to learn consequences for violence