Biomedical subjects

G G Bernston

Publications and source records attributed to G G Bernston.

2 recordsLinked to original sources

PubMed1996

Quantity-based interference and symbolic representations in chimpanzees (Pan troglodytes).

Five chimpanzees with training in counting and numerical skills selected between 2 arrays of different amounts of candy or 2 Arabic numerals. A reversed reinforcement contingency was in effect, in which the selected array was removed and the subject received the nonselected candies (or the number of candies represented by the nonselected Arabic numeral). Animals were unable to maximize reward by selecting the smaller array when candies were used as array elements. When Arabic numerals were substituted for the candy arrays, all animals showed an immediate shift to a more optimal response strategy of selecting the smaller numeral, thereby receiving the larger reward. Results suggest that a response disposition to the high-incentive candy stimuli introduced a powerful interference effect on performance, which was effectively overridden by the use of symbolic representations.

Animals↗

PubMed1994

Bioelectrical echoes from evaluative categorizations: I. A late positive brain potential that varies as a function of trait negativity and extremity.

Attitudes can be conceptualized in terms of the elementary operations of evaluative categorization and response selection-execution. This article describes a component of the event-related potential that is associated with the first of these operations. Ss were exposed to sequences of 6 traits and performed a dichotomous evaluative categorization task. Evaluative inconsistency was varied by embedding very positive, moderately positive, moderately negative, and very negative traits in sequences containing predominantly very positive traits. Highly and moderately evaluatively inconsistent traits, compared with mildly inconsistent or consistent traits, evoked a larger amplitude late positive potential (LPP) that was maximal over centroparietal regions. Furthermore, extremely evaluatively inconsistent traits evoked a larger amplitude LPP than moderately evaluatively inconsistent traits even though both sets of traits were judged to be negative.

Affect↗