Overtraining and optional shift behavior in rats and children.

Abstract

Following training to respond to 1 dimension of a 2-dimensional discrimination, rats and 3-and 4-yr.-old children had the option of learning a second discrimination by executing either a reversal or an extradimensional shift, or by responding nonselectively. Rats received 0, 200, or 300 overtraining (OT) trials in the initial discrimination, and children 0 or 100 OT trials. OT increased the proportion of optional reversal shifts (RS) in children but tended to decrease it in rats. Optional RS was relatively infrequent in rats as compared to children. In both species preference for RS varied with the dimension relevant in the initial discrimination.

Dimensional Preference and Discrimination Shift Learning in Children

“…From this viewpoint it is somewhat surprising that prior preference testing in the present experiment did not also influence selection of optional shift, since earlier studies employing prior preference tests have reported a relation between dimension preference and both learning speed and shift performance (Heal et al 1966;Smiley & Weir 1966). It seems unlikely that the failure to find an effect on shift selection is due to a "ceiling effect" in frequency of RS selection, since considerably higher percentages of optional RS have been observed in other studies with Ss of comparable age (e.g., Smiley & Weir 1966;Tighe & Tighe 1966). One possibility is that the preference test procedures of the Heal et al and the Smiley and Weir studies were likely to have had a greater strengthening effect on S's selective response than those of the present experiment.…”

“…Such control has been clearly demonstrated elsewhere (Tighe & Tighe 1966). Nor does it maintain that dimension preference tests necessarily bias our view of the contribution of a given dimension preference to discriminative performance.…”

The effects of dimensional naming upon children’s performance in a modified optional shift problem

“…The larger difference for nonreversal shifts is, of course, due to the fact that, although verbal labeling produced high levels of both types of shifts in this experiment, uninstructed 7-year-olds have astronger tendency to make reversal shifts (60%) than nonreversal shifts (28%). In the more general context of other optional shift studies, the tendency to make optional reversal shifts as opposed to nonreversal shifts has been shown to be a function not only of age, but also of several experimental variables in addition to verbal labeling, including dimensional salience (Smiley & Weir, 1966;Tighe & Tighe, 1966b, 1970, perceptual pretraining (Tighe & Tighe, 1970), and novelty of the nonreversal dimension during shift learning (Eimas, 1967). In this context, the present study not only replicates the earlier findings regarding labeling on the reversal dimension, but also goes a step further in showing that labeling of values on the nonreversal dimension produces a high percentage of nonreversal shifts.…”

The effects of fading procedures on discrimination shifts.

“…Specific aspects of the training conditions also affect the acquisition of the covert response. For example, under a number of conditions, overtraining on the original discrimination facilitates reversals in young children (e.g., Eimas, 1966;Tighe & Tighe, 1969;Youniss & Furth, 1964), presumably by enhancing weak covert responses. College students, however, seem not to be subject to the overtraining reversal effect even when given substantial amounts of overtraining (e.g., Nolan & Anderson, 1973).…”