PSYC 3F40 Lecture Notes - Metabolic Disorder, Eating Disorder, Triglyceride
33 views3 pages
Published on 4 Feb 2013
School
Department
Course
Professor
Learned Helplessness:
•a response to exposure to an inescapable aversive stimulus, characterized by
reduced ability to learn a solvable avoidance task; thought to play a role in
the development of some psychological disturbances
•organisms can learn that they have no control over their destiny
Maier and Seligmen(1976)
•Experiments demonstrating that animals can learn that behaviour doesn’t
affect environmental events
•Dog placed in apparatus where it received electric shocks that could not be
avoided, then placed the dog in an apparatus where electric shock was
preceded by warning (shock could be avoided by stepping over barrier to
other side)
•Dogs in control group learned to avoid the shock, but if dog previously
received inescapable shocks it failed to learnlearned to be helpless
•Implications: when people have experiences leading to helplessness
lowered expectation that trying will lead to success
•Learned helplessness has characteristics of personality traitpeople with
history of learned helplessness will stop trying in other aspects of life
Eating
•Need to eat shaped evolutionary development of our species
Causes of hunger
Physiological factors body needs nourishment
•Canon and Washburn(1912)
ohunger results from empty stomach, thirst from dry mouth (spit and
rumble theory), but people without stomachs still feel hunger
•Depletion of nutrients is more likely cause glucose and fatty acids
•Short-term reservoirin liver and muscles
•When glucose is eaten, some is used for fuel, and rest is converted to
glycogen and stored in liver
•glycogen: an insoluble carbohydrate that can be synthesized from glucose
or converted to it, used to store nutrients
•long-term reservoir consists of adipose (fat) tissue, under skin and in
abdomen
•when glycogen level is low, body goes to long-term supply (during prolonged
fast)
•glucose feeds the brain
•Mayer(1955)
oGlucostatic hypothesis: hunger is caused by low level/availability of
glucose, condition monitored by specialized sensory
neurons(glucostats)
oLed to discovery of 2 detectors in the livermeausure glucose and
fatty acids
oThis detector system only occurs when blood is severely depleted of
nutrients
Social and Cultural Factors