Classical Conditioning of Skeletal Avoidance Responses in Two Strains of Rats

Abstract

Anticipatory skeletal responses can be directly elicited during classical aversive conditioning in the shuttlebox. Under the classical CS-UCS contingency Long-Evans rats shuttle at moderate rates, while Fischer344 rats display high rates of anticipatory responding, even though the instrumental avoidance contingency is absent. The classical contingency is also exceedingly important in determining the differences between these strains, as well as their initial and terminal rates of anticipatory responding, when the avoidance contingency is present.

Bidirectional avoidance by mice as a function of CS, US, and apparatus variables

“…Specifically, a buzzer was an effective avoidance signal even in conditions producing a marked suppression of intertrial responses. Of course, an understanding of CS modality effects also requires extensive information on unconditioned, pseudoconditioned, and classically conditioned responses to various types of stimuli (see, e.g., Izquierdo & Cavalheiro, 1976;Jacobs & LoLordo, 1980;Katzev & Mills, 1974;Myers, 1960Myers, , 1965Oliverio, 1968;Sigmundi & Bolles, 1983; for the aversive properties of acoustic stimuli on mice, see Baron & Kish, 1962). …”