1 LEARNED HELPLESSNESS Seligman, Maier, & Overmier’ s [late 1960’s] boss dog studies. Stage 1: Boss dog in hammock can control shock to foot with head swing while deputy dog cannot. Yoked control= Ncell= 8; 6 milliamps for 30 sec’s each X 64. Note nisbett and S = 350-1450 milliaamps. Stage 2 – 24 hrs later: Dogs in shuttle box with one side electrified on floor [foot shock for 60 sec’s over ten trials] but escape possible-jump low wall. Boss dog learns fast. Deputy dog does not escape [6 of 8 dogs 75% tolerate 9 –10 shocks. If tested 7 days later a new batch of deputies also escapes poorly= 60 % tolerate all ten. Generality and variations: many species [rats, dogs, cats, people]; many stressors-noise, crowding, cold, defeat, restraint, pain. True when stage 1 done under curare for helpless animal. Target behaviors: escape, shock elicited aggression, competition for food, immune function and health. 2 e.g. Cohen et. al. 1992 Inescapable changes in social structure drops immunity in chimps. Sklar & Anderson 91 more tumors in cancer prone rats after L.H. Why?: Seligman and Maier’s preferred answer: A) Yoked animal has learned an idea = “I cannot prevent pain [or at least foot shock] . My actions have no impact [here?].” or Outcomes are not CONTINGENT on my behaviors. This represents a cognitive deficit = a mental block to seeing that escape IS possible in new setting. The animal has LEARNED HE/SHE IS HELPLESS. B) Animal is so bummed that he/she is not motivated to try new behaviors. Lost hope>no behavioral juice a la drive theory. Note: animals have ideas. The ideas are not tied to specific settings [new stim are eliciting helpless r]. It’s not S(1) > R(1). Opposing views: L.H.> analgesia. Escape less cause it hurts less. Tested with tail flick to shock. Yes. Release of endorphins??? But rat work mainly and doesn’t disprove that L.H. idea> analgesia. 3 Weiss and friends: a two “flavors” view. Most rat studies test for Lh 30 min later. No Lh in dogs 48 hours later in O & S 67 but in another [S & M 67] Lh 7 days later. Learning is supposed to be permanent so why not 48 hours later?? And whats with the inconsistancy?? Flavor # 1: Rat work and Overmier & Seligman 67 used short, intense shock. Might this deplete nt’s such as Epin and nor ep so much that action stops?? If so, it would be only temporary until nt’s bounce back-like an hour later and certainly by 48 hours later. So most rat Lh of this type could be due to shortage of nt juice. Flavor #2: Long, moderate [1 milliamp] shock > initial stuggle and action then waiting and then shock offset = neg Sr. for what??? Inaction. This form of LH should last. 4 Data: Flavor #1- Weiss, Stone and Harrell 1970. Rats given Lh. Trt over 14 days of one trial with strong, short shock. Control rats get no days. Then on day 15, all get one strong short unavoidable shock, and then given a second avoidable shuttle box shock. Who escapes?? Rats should adapt to stress with less nt loss over time. If so, 14 day rats should show LESS LH than controls if Weiss is correct. If its learned H. if anything 14 day rats should show MORE LH than controls. Only Naïve Controls show poor escape and also less brain noreph. Flavor #2-Glazer and Weiss 1976 The Nosing study. Rats receive long weak shock Day 1: Rats-60 inescapable tail shocks of 1 milliamp for 6 sec . Controls get no shock 72 hours later given chance to escape in one of several settings. Some require high activity such as FR 3 Bar Press; FR 2 shuttle box. While one required stillness = nosing a target. Lh helped nosing and hurt high activity escape beh. [repl with yoked design]. 5 Other data: Weiss, Stone and Harrell 1970 Autopsies of rat brains show less noreph in Lh. Animals. Glazer, Weiss, Poherecky and Miller 1975 Admin tetrabenzamine to naïve rats. This depletes noreph chemically. These drugged animals do worse at high activity escape but are ok on nosing escape. Then give rats MAO inhibitor that elevates noreph in brain. They are immune to Lh manip. This manipulative work shows that in rats, nt depletion plays a key role in “Lh” triggered by intense sudden stressors and suggests that some forms of freezing under stress could be due to same type of mech. But in human research a good deal of belief that Lh is a cog/motiv problem as orig. stated by Seligman. Extended as one explanation for depression Lynn Abrahamson, Seligman and Teasdale. Neg events attributed to Global, Stable & internal causes= depressive attributional style. Stable/External>Anger; [note: orig uncontrollable pos events also>Lh.} 6 Optional: Strategy 1: does Lh manip create bad mood and or depressed feelings in normals. Sort of but is it the same intensity?? Strategy 2. Compare depressed to normals after Lh. Manip on such things as expected future success; task persistance; escape beh. [correl strategy] Strategy 3. Compare attrib made by depressed and normals following Lh Strategy 4 compare attrib for real bummers for Dep and normals and does it correl with meas of attrib style...Data confused Strategy 5 Manip attrib style among depressives and look for depr change. Style manips not so powerful but manipulation of specific depressive thoughts is more effective [Beck]. Cognitions and attrib clearly do play a role in maintaining depression and can be used to control it but in many cases the core cause is physiological. Nevertheless, Lh has become a core perspective in thinking about human responses to stress. Generally accepted that in stressful settings it is beneficial to decrease helplessness by upping perceived control and self efficacy. Seen more in following sections.
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