Discrimination Shifts as a Function of Degree of Original Learning and Materials in the Original and Shifted Discrimination Tasks

Concept-shift and discrimination-reversal learning in humans.

“…The above-reported failures to obtain any significant effect from changing the cues of + D during TL stand in contrast to Sugimura's (1960) finding that 2ED shifting is markedly facilitated by eliminating +D altogether (i.e., by holding +D cues constant in TL). This result, taken with those of Heal and Bedrosian above, strongly suggests that it is through perseveration to +D rather than through perseveration to +c that PR% (Di-) interferes with ED shift.…”

“…Ten studies found no significant difference between criterion-trained and SOT groups: Youniss and Furth (1965); Heal (1966), with normals; Marsh (1964); Tighe and Tighe (196S); Sugimura (I960), for 2ED, +D held constant; Iwahara and Sugimura (1962), normal and retarded adults; Zach (1964); Viney (1964); Hochman (1966); and Furth and Youniss (1964). All studies but those of Iwahara and Sugimura (1962) and Sugimura (1960) involved normal children (CA < 13 years) and used either ED S , ED C -, or ED n . Iwahara and Sugimura (1962) used both normal and retarded adults and 2ED C , and Sugimura (1960) used older teenagers and two unique paradigms.…”

“…According to a simple S-R analysis (such as that of Buss, 1953) it would be expected that instrumentalresponse perseveration should play the greater part in the effect; a mediational analysis, on the other hand, might favor the alternate explanation. Several studies (Bedrosian, 1966;Heal, 1966;Milgram & Furth, 1964;Sugimura, 1960;Uhl, 1966) bear on this issue. Milgram and Furth (1964) trained 6-and 9year-olds on a three-choice OL discrimination in which the positive cue from the relevant visual dimension was always found in the same position.…”

“…Third, unless the intent of the study was to investigate ease of shift as a function of several degrees of training (e.g., Sugimura, 1960), studies in which Ss were shifted prior to solution of the original problem (Bower & Trabasso, 1963;Walk, 1952) are not included. These studies, being motivated by theoretical concerns other than those of interest here (i.e., the continuity-noncontinuity issue; the question of one-trial learning), are better considered in these other contexts (e.g., Blum & Blum, 1949).…”

Overtraining and stimulus change in extra-dimensional shifts

“…(2) Consonant with the hypothesis that shift arrangement is an effective variable in the above studies, Walther (1962) and Sugimura (1960), in the only experiments which compared the effects of overtraining on different EDS arrangements, found that the magnitude of overtraining facilitation in adults was inversely related to the degree of stimulus change occurring between original learning and shift. This effect, however, was not statistically significant in either study.…”