CER

My Response to Assignment 2:


The goal of in my first and second classical conditioning experiments was to have Sniffy acquire classically condition response, therefore, I did not reward Sniffy for anything; instead I used the tone as an unconditioned stimuli (US) or neutral stimuli that does not result in overt behavior. I used a shock as a conditioned stimuli (CS). I know the shock is the US because it has the intrinsic ability to elicit an obvious behavior in nearly any subject. Pairing the sound of a tone with an electric shock, fear conditioning establishes a CER quickly. After one or two pairings, the sound of the tone will send a wave of apprehension through amygdalar circuits of any organism capable of processing fear.



The tone CS and the shock US were paired in differing intervals so that the rat, Sniffy, would acquire a conditioned emotional response (CER) of fear (unobservable brain activity) and movement responses based on learning that the tone would be followed by a shock. Tone;ShockMovement/Fear (movement is recorded as lack of movement too).



In the basic acquisition (Exercise 1),Sniffy receives 10 pairings of medium-intensity tone (CS) with the medium-intensity shock (US). Sniffy’s movement increases from zero to about 7. Bar pressing slows to an eventual stop, and CS response strength mind increases. Sniffy’s psychological state is producing observer able behavior. Sniffy now has a CER to a medium-intensity tone CS. This fear/pain based CER is a [mind] response, outwardly characterized by jumping, freezing, and failing to push the lever. (lever pushing will only display in rats previously conditioned to do so.)



Extinction is the goal of Exercise 2, where 30 extinction trials are executed using a stimuli of medium-intensity tone CS and no shock US. (note; a CER takes longer to extinguish than it takes to acquire thus more extinction than acquisition trials). The CS Response Strength mind window indicates the mind is settling compared to the trails in Ex1. By the end of Ex2 the mind has settled. The movement window mirrors the mind window and shows the body settling (for a rat this settling could be uncharacteristic or like freezing and may indicate some nervousness brought about by the tone CS.



Exercise three is set up so that Sniffy will experience spontaneous recovery. First, Sniffy has a time out, later, returning to the experiment cage where only a medium-intensity tone CS is set as stimuli (with no shock US). Sniffy’s movement spike (from .1 in Ex2 to .5 in the first trial of Ex3). Again the Movement and the CS Response Strength mind windows are mirrors of one another, displaying results of a settling mind and body.