PSYC 340 1st Edition Lecture 18Learned Helplessness What you missed last class (04.02)I. Optogenetics A. Channelrhopdopsin – illumination allows Na+ ions to ender the cellB. Halorhodopsin – illumination allows Cl- flux C. Placed under the control of tTA promotorII. Response-Outcome Learning A. Criteria 1. The behavioral modification depends on a form of neural plasticity. 2. The modification depends on the organism’s experiential history. 3. The modification outlasts the environmental contingencies used to induceit; the experience has a lasting effect on performance 4. Imposing a temporal relationship between a response and an outcome alters the response III. Ways of studying instrumental behavior A. Reward training B. Omission training C. Punishment D. Escape IV. Appetitive Reinforcers A. Reward training (positive reinforcement) 1. Performing the response produces an appetitive stimulus 2. Increase behaviorB. Omission (negative punishment) 1. Performing the response prevents/eliminates the occurrence of an appetitive stimulus 2. Decrease behaviorV. Aversive Reinforcers A. Punishment (Positive punishment) 1. Performing a response leads to an aversive stimulus 2. Hitting a dog with a newspaper 3. Decreases behaviorB. Escape (Negative reinforcement) 1. Response contingent shock 2. Increases behavior VI. Common behavioral principles A. Preparedness – already prepared to make connections between taste and sickness These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.B. Adding extra (free) reinforcers degrades performance C. Learned helplessness 1. Overmeir, Seligman, and Maier 2. Much like US pre-exposure effect 3. Triadic design 4. Motivation – cognition of no control 5. Associative – knowledge of the lack of association between behavior and shock undermines new learning VII. Therapy A. If cognition is critical, we should be able to reverse it/prevent it by showing the animals they have control 1. Can we reverse it if we show you that you have control? 2. Yes, yes we can reverse learned helplessness! a. You do have to show/train them though VIII. Immunization A. Opposite order of therapy 1. Having known that shock is controllable beforehand works 2. Protect against a deficit IX. Role of Endogenous Opiods X. Learned helplessness and disease Learned Helplessness (Continued) I. Role of the dorsal raphe nucleus and the vmPFC A. DRN = dorsal raphe nucleus 1. Induction of helplessness 2. Serotonin = 5HTa. Learned Helplessness – depression-like state 3. If you lesion this area, they will not show helplessness4. Essential for learned helplessnessB. vmPFC = ventral medial prefrontal cortex1. Beneficial effects of controlled stimulation 2. Can still learn to perform an instrumental response3. If you lesion this area, they will later show learned helplessness 4. Essential for blocking the effects of shock a. Controllable stimulation only prevents helplessness if you have a vmPFCII. Mechanisms A. Instrumental learning within the spinal cord 1. Can lower level systems in the spinal cord learn? 2. Spinal cord as the highway – only part a. Outer white matter ring cord – part of it that we discuss as a conduit i. Paralysis comes from a disruption of the white matterb. Central gray – millions of neuronsi. Spinal cord can learn by itself! 3. How can we study this?a. Under anesthesia, you sever the connection between the lower spinal cord and the braini. Sever the thoracic region; cervical region still works ii. Brain does not directly control the lumbar region (steps) - Brain just says “step,” and the lumbar has more central control iii. The rat wouldn’t really cognitively notice paralysis b. Since the brain does not control it, you can teach the lumbar part of the spinal cord can learn to step on its own without being connected to the brain! i. SO COOL!!! c. Can even teach it to step over obstaclesB. Triadic design1. Controllable stimulation fosters learning 2. Uncontrollable stimulation undermines learning 3. Is this just a change in the reflexive circuit? a. Because of the triadic design, you can see that the spinal cord is actually learning! b. It’s like learned helplessnessC. Immunization and therapy effects 1. You can do the same thing with all of this as you can with learned helplessness. D. Uncontrollable stimulation disrupts recovery after spinal cord injury 1. Doesn’t know what to do with all the pain signals 2. Literally destroys any remaining neurons after a severe injury 3. Same effect with peripheral inflammation 4. Quiet the spinal cord down – can help to preserve the neural tissue a. Don’t use morphine – can really mess stuff up b. Hypothermia really helps though Theories of Reinforcement I. Hull II. Reinforcers satisfy the biological needs of the organism A. Drive reduction B. Problems with Hull’s approach by itself 1. Implausible drives a. Will the animal work for it?b. Monkey hits a lever to open a window to see a toy train moving around i. Monkey will work for it!ii. Suggests that it is a drive—but is it really? - Get a long list of drives – curiosity, entertainment, etc. c. Are all of these drives plausible? 2. Circularity a. The only way we can tell that it is a drive is the reinforcement i. Sight of moving train increases responding b. Endless cycle c. Hullians talk about transituationality i. Drive can explain behavior over a variety of different situations3. Drive reduction is not necessary a. Hullians say you have to meet the biological need; if you don’t, then you won’t learn b. Rats will run in a t-maze for saccharine, though it does not help with a biological need c. Rat
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