Conditioned heart-rate change in the pigeon: Analysis and prediction of acquisition patterns

Abstract

A large sample of pigeons (n = 458) was trained in a classical conditioning paradigm where whole-field retinal illumination and foots hock were paired to produce conditioned heart-rate change. Analysis of the acquisition data indicated two distinct learning patterns (denoted C and C), and any given group of animals can be ~haracterized by describing the proportion of animals showing each acquisition pattern (the C:C ratio). It is shown that mean learning curve variability among groups is largely a function of group differences in this ratio, such that accurate prediction of mean learning curves is possible knowing only this parameter. Furthermore, this ratio is itself predictable only from responses to an initial visual stimulus presentation. Consequently, from reactivity (orienting response) to a single presentation of the to-be-conditioned stimulus, it is possible to predict accurately the mean learning curve of any given group.

Modification of the discharge of lateral geniculate neurons during visual learning

“…The results are from a vertebrate model system we have been investigating for some years-visually conditioned heart rate change in the pigeon (Cohen, 1969(Cohen, , 1974. In developing this system, an effective behavioral paradigm has been extensively characterized (Cohen and Goff, 1978) and progress in describing the relevant circuitry (Cohen, 1980) has been sufficient to allow cellular neurophysiological analysis. The first such studies were of the "cardiac motoneurons," both vagal (Gold and Cohen, 198 la, 1984) and sympathetic (Cabot, 1976;Cohen, 1982).…”

Enhancement of heart rate responses during conditioning and sensitization following interruption of raphe-spinal projections

“…The conditioning performance of the 33 sham-operated control birds was equivalent in all respects to that of control animals previously studied in this laboratory (see Cohen, 1974;Cohen and Goff, 1978). Briefly, conditioned heart rate change began developing within the first few light-shock pairings and became stable within 20 such pairings (Fig.…”

“…The initial study was an exploration of the effects of raphe lesions on heart rate conditioning, and it included two experimental groups with corresponding sham-operated control groups. To reduce variability due to such factors as health and seasonal variation, a stratified control procedure was followed in which a sham-operated bird was trained concomitantly with each experimental bird (Cohen and Goff, 1978).…”

“…The apparatus and general procedures were similar to those employed in previous heart rate conditioning studies in this laboratory (e.g., Cohen and Durkovic, 1966;Cohen, 1974;Cohen and Goff, 1978). Briefly, birds were semi-restrained by an elastic bandage and placed in a dark conditioning chamber.…”

Thermoregulation mediated by conditioned heart-rate changes in pigeons

“…Our experiments suggest that it may not be valid to assume that the autonomic thermoregulatory responses of birds are innate and unmodifiable but that rather they may become established and be maintained through conditioning, not unlike what is thought to be the case with some behavioural thermoregulatory reactions. In this context it may be useful to keep in mind that the cardiac activity of birds is easily modified through classical, Pavlovian conditioning (see, for example, Delius and Tarpy 1974;Cohen and Goff 1978), although this has not yet been demonstrated in a thermoregulatory context. Learning processes could be useful in bringing about the optimal integration of behavioural and autonomic thermoregulation mechanisms (Schmidt 1978a;Schmidt and Simon 1979) where other organismic needs than homoeothermy may also have to be considered in as far as they compete for effector control (see Rautenberg et al 1980;Gabrielsen et al 1977; Gabrielsen and Steen 1979).…”