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D L Hoats

Publications and source records attributed to D L Hoats.

8 recordsLinked to original sources

Effect of typicality level on proactive inhibition in adults with mental retardation.

Adults with mental retardation heard four triads of highly typical, atypical, or unrelated words (Experiment 1, proactive inhibition buildup) and three triads of typical, atypical, or unrelated words, shifting to either typical or atypical words (Experiment 2, inhibition release). Our purpose was to examine the structure of their semantic system and determine whether they encode information in semantic memory on the dimensions of item prototypicality and list organization. No list differences occurred in Experiment 1. Apparently, interference effects inhibited encoding by organization and typicality. Amount of release varied as a function of item typicality and list organization (Experiment 2), demonstrating multidimensional encoding in semantic memory.

Adult

Comparison of mentally retarded and nonretarded persons' organization of semantic memory.

The production frequency of exemplars for 16 categories was obtained from institutionalized mentally retarded adults and compared with those of nonretarded children, adolescents, and adults and with typicality ratings given by the same retarded subjects previously. The production frequency of exemplars by retarded and nonretarded persons was remarkably similar and varied more as a function of specific category than of mental development. Production frequency and typicality ratings of the retarded persons were less reliable. There is a striking similarity in the structure of the semantic memory of retarded and nonretarded persons.

Adult

Comparison of verbal typicality judgments of mentally retarded and nonretarded persons.

In Phase I of this study, mentally retarded adults judged whether exemplars were members of their respective categories. In Phase II they judged how representative the exemplars were of their categories. Comparisons were made between this group and the nonretarded groups of Bjorklund, Thompson, and Ornstein (1983) and Uyeda and Mandler (1980). There was little evidence of a developmental relationship between typicality ratings given by retarded and nonretarded persons, but there were significant relationships among the groups for specific categories. Relationships were more category-than mental age-dependent. Other analyses indicated that Rosch's (1975) finding that typical exemplars are incorporated into category structures prior to atypical exemplars was replicated with retarded persons.

Adult

Effects of isolation by color on mentally retarded and nonretarded persons' recall of printed words.

Mentally retarded and nonretarded persons of equal mental age read lists of nine nouns presented simultaneously in a horizontal format. In the control condition all words were colored blue; in the experimental condition the fifth word was colored red (isolated). Recall of items when isolated was reliably higher than when not isolated for both groups. The proportion of fifth-position items recalled compared with total recall was almost identical for both groups whether or not the items were isolated. Results were discussed in terms of interference theory and the pedagogical implications of superior recall of words isolated by color.

Adolescent