An apparatus and procedure for effective instrumental training of neonatal and infant rats

Abstract

Following introductory remarks on the necessity of being able to detect learning disabilities and other behavioral impairments in animals at an early age, an apparatus and procedure for the escape training of neonatal rats are described. In this apparatus, both 5-and 7-day-old rats were shown to have improved their performance, in terms of a speed increase, over a 25-trial training session. A procedure for active avoidance training in the same apparatus is also described and its effectiveness is demonstrated in the behavior of trained lO-day-old rats relative to that of yoked controls. The appropriateness of the described app.aratus for the instrumental training of neonatal and infant rats is discussed in relation to that of other apparatuses that have been used for this purpose.

The effect of home cage stimuli on acquisition and retention of an active avoidance response in previsual rats

“…The multidirectional shock well used for training and retraining has been previously described (Misanin et al, 1974). The grid floor was 10.5 cm square and consisted of 1-mm diameter rods spaced 4 mm apart (center to center).…”

“…A change in stimuli immediately after training, during the 30-min retention interval, was found to have a greater impact on retention performance than stimulus change introduced at the time of the retention test. The implications of these findings are discussed in relation to ontogenetic differences in retention performance and theories of forgetting.While previsual rats as young as 10 days of age have little difficulty acquiring an active avoidance response (AR) (Misanin, Chubb, Quinn, & Schweikert, 1974; Misanin, Turns, & Hinderliter, 1985), they do have difficulty retaining the response over even very short retention intervals. Misanin et al (1985) found retention deficits as soon as 5 min after training and retention loss seemed complete 30 min after training.…”

Long-term retention of a conditioned taste aversion in preweanling and adult rats

“…These studies employed cyclophosphamide as the US and used both single-bottle and preference tests. Further complications arise from the fact that none of the above studies included all control conditions necessary to determine the nonassociative influence of early experience with poisons or tastes on subsequent adult taste preference.In view of the bulk of data substantiating the phenomenon of infantile amnesia in a variety of aversive (Campbell & Campbell, 1962;Feigley & Spear, 1970; Kirby, 1963;Misanin, Chubb, Quinn, & Schweikert, 1974;Smith, 1968) and appetitive paradigms (Campbell, Jaynes, & Misanin, 1968), it is of theoretical importance to investigate the generalizability of infantile amnesia with respect to taste aversion learning. The present experiment was, therefore, designed to compare the retention of taste aversions by mature and immature organisms, employing the necessary control conditions.…”

Alleviation of forgetting in preweanling rats

“…Tasks employed previously to study instrumental learning and retention by preweanlings have most often required simple escape or discriminated escape from electrical shock (although preparations for appetitive instrumental conditioning of neonatal rats have begun to appear, e.g., Anisel, Letz, & Burdette, 1976; Kenny & Blass, in press). The present experiments employed an avoidance task based on the nondircctional escape task devised by Misanin, Chubb, Quinn, and Schweikert (1974). These experiments followed a long series of pilot studies in which a number of control conditions were determined to be necessary to allow conclusions about retention.…”