Age related changes in the effectiveness of name and visual codes in recognition memory

In the first of three studies college, third grade, and kindergarten Ss were able to determine that two stimuli presented 700 msec apart were the same more quickly if they were visually identical than if they shared the same name. If 3000 msec elapsed between stimulus presentations third grade and college Ss responded at the same rate in making both types of matches, whereas kindergarten Ss appeared to continue to respond more quickly in making visual matches. Study II was an unsuccessful attempt to replicate the kindergarten finding. A warning signal, presented 500 msec prior to the second stimulus, reduced RTs at both interstimulus intervals, but no significant differences in making visual and name matches occurred. In Study III first-graders, responding either with or without a warning signal, were found to respond like the older Ss in Study I. The warning signal again reduced RT at both intervals. The results suggest that Ss across a wide age range are able to use the visual properties of a stimulus for only a very brief period as the basis for making matching judgments.     

Retrieval processes in recall

A reaction time (RT) paradigm was developed to study retrieval processes in paired associate (PA) recall. Prior to the experimental session, subjects learned lists of PAs (varying in length from three to 24 pairs); during the experimental session, subjects' RT to say the response word from the onset of a visually presented stimulus word was measured. The implications of several classes of retrieval models were discussed in the context of this paradigm. The shape of the RT-list length function, practice, and sequential effects were all of interest in distinguishing among models. Four experiments were reported which were designed to (1) establish the baseline effects in this paradigm, (2) determine which of these effects should be attributed to the retrieval stage of processing, and (3) investigate the effect of semantic memory in this task. Results suggest that simple serial scanning models are inadequate to handle the data from this task. Strength, direct-access, or parallel processing models, on the other hand, seem to capture the qualitative effects present in our experiments. When a strength model was formalized and fit to the data from Experiment I, it was found that a two-trace version gave good quantitative fits while a one-trace version did not, suggesting that both short- and long-term memory independently contribute in this task.     

Using conjoint-measurement models to investigate a theory about probabilistic information processing

A theory of how opinions are formed and revised on the basis of probabilistic evidence is presented. The decision maker is viewed as a limited information processor who attends to the dimensions of a sample of equivocal information in a sequential fashion, beginning with the most salient dimension and continuing in decreasing order of salience. The contribution of each dimension level to the final opinion depends on the strength of association between that level and each of the two hypotheses under consideration. This theory is represented formally as an additive-difference model, various special cases of which correspond to other algebraic models in the literature. Two of the special cases were empirically investigated under varying levels of experience and payoffs, using the techniques of conjoint-measurement theory and ordinal data from individual subjects. The data provided reasonably good support for the models under all conditions investigated, and in addition showed interesting effects on salience and on processing of the independent variables.     

Motivation concepts and sexual identity

The association dimension of the Picture Identification Test (PIT) was used to investigate the motivation concepts of male and female university students classified as Declared Homosexual, Sexually Uncertain, Clinical Control, and Normal Control. The t test was used to identify Need Association Dyads which discriminated (p < .01) groups. Greater than chance numbers of variables discriminated each of the pairs of groups within each sex except the Sexually Uncertain versus Clinical Control Male groups, the Declared Homosexual versus Clinical Control Female groups, and the Declared Homosexual versus Normal Control Female groups. PIT Need Association Dyads were discussed as a type of implicit personality theory assessment with emphasis on the beliefs subjects hold about the simultaneous expression of needs.     

Handedness and sex differences in hemispheric asymmetry

A study was designed to assess the contributions of the factors of sex and familial history to cerebral dominance, where cerebral dominance was inferred from laterality on a dichotic listening task. The 144 subjects were selected from a larger sample on the basis of handedness, sex, and familial history of sinistrality, and tested on a task involving the dichotic presentation of CV syllables. Analysis of the data indicated that in female subjects, the presence of familial sinistrality increased the likelihood that they present atypical left-ear superiorities, while in males the converse was the case. Moreover, there was a significant sex difference overall, such that males were more clearly lateralized than females. A review of other dichotic listening studies provided support for the reliability of this sex difference for dichotic tasks using verbal material. A review of the clinical literature indicated that the hypothesis of a sex difference is at least tenable and merits further investigation. However, the possibility that there is a sex difference in the cognitive strategy used in dichotic listening cannot be ruled out.     

Evaluating socioeconomic status bias in the WISC-R

The use of intelligence tests in making special education placement decisions for children has come under repeated scrutiny in recent years. Arguments for and against the use of IQs have centered around the issue of test bias. In California a permanent moratorium on the use of intelligence tests in placing minority group children into classes for the educable retarded has been handed down by the court. One defense proposed by advocates of mental testing has been that the tests are biased against socially and economically disadvantaged groups irrespective of race. According to Clarizio (1978), if a test predicts equally well for two groups it can not legitimately be described as biased. The purpose of this investigation was to evaluate the test bias of the Verbal IQ as measured by the Wechsler Intelligence Scale for Children-Revised in relation to predictions of academic achievement in two different socioeconomic status groups. The results indicated that Verbal IQs are not biased with respect to socioeconomic status. Derived regression equations are presented along with an analysis to inspect the statistical power of the original tests.     

Transfer of conditioned appetitive stimuli to conditioned aversive excitatory and inhibitory stimuli

The transfer of Pavlovian appetitive stimuli to Pavlovian aversive stimuli was examined in three experiments. In Experiment 1, rats received appetitive (Ap) conditioning designed to establish a flashing-light stimulus as either a CS+, CSo, or CS? for food, or to maintain it as a novel stimulus for US-alone subjects. Then, the stimulus was employed as a signal for weak shock in conditioned-emotional-response (CER) training. Both acquisition and extinction results showed that the ApCS+ facilitated and the ApCS? retarded aversive excitatory conditioning relative to the ApCSo and US-alone controls. Experiment 2 replicated the findings of Experiment 1 with both a moderate and a severe shock in CER training. In Experiment 3, different groups received the same appetitive conditioning as before, but to a flashing-light stimulus which was then employed as a signal for no shock in CER training. The ApCS? facilitated and the ApCS+ retarded aversive inhibitory conditioning relative to ApCSo and US-alone controls. Collectively, these findings establish that, in Pavlovian conditioning, transfer of an appetitive CS to an aversive excitor or inhibitor is facilitated by maintaining the initial conditioning contingency.