Integration of features in comparing multifeature stimuli

For a series of trials, the subject indicated whether or not two face-like stimuli were identical with respect to the features they contained (a positive or negative response, respectively); reaction time (RT) was recorded. The stimuli were separated by .5 or 4.0 sec, and each contained either two or three features. On some trials, the features of the first stimulus were represented within a single head outline; on others, they were distributed over several spatially separated outlines (components). Positive-response RT increased with the number of stimulus features and with the number of first-stimulus components (c); these two factors were additive. Negative-response RT increased with c, decreased with the number of differing features, and these two factors interacted. These effects did not vary with interstimulus interval. The results indicate that the subject did not integrate the first-stimulus components, but instead compared the second stimulus to each component, holistically (for positive responses) or analytically (for negative responses).     

Using visual codes for comparisons of pictures

In two experiments, Ss indicated for a series of trials whether or not two pictures of common objects had the same name (a positive or negative response, respectively). The pictures were separated by one of three interstimulus intervals (ISis), and reaction time (RT) was recorded. In Experiment I, positive trials involved pictures that were identical (identity match), mirror images (mirror match), or physically different but had the same name (name match). The stimuli came from either an S set, in which name-match pairs were physically similar, or a D set, in which name-match pairs were physically dissimilar. The mean RTs for mirror and identity matches were virtually the same but faster than name-match RTs, an advantage that decreased with increasing ISI. It was expected that name-match RT for the S set would be less than for the D set, indicating a facilitative effect of physical similarity; however, the identity-match RTs showed the expected difference. These results were extended in Experiment II, which involved only the identity and name matches, in pure sessions (which included positive trials of just one type) or mixed sessions (which included both types of positive trials). For mixed sessions, name- as well as identity-match RTs differed between the S and D sets. These results provide evidence for the use of visual codes in comparing nonidentical pictures, codes that apparently vary with experimental context and task demands.     

Bilateral tachistoscopic perception,handedness, and laterality: II. Nonverbal stimuli

Thirty-two Subjects were assigned to four groups on the basis of handedness (left or right) and familial sinistrality (absent or present). Their laterality patterns were investigated with a cued order-of-report paradigm. On each trial, Subjects saw a tachistoscopic presentation of two outline drawings of common objects, one drawing on the left of a central fixation point, one on the right. A centered arrowhead appeared with the pictures; the arrowhead pointed either left or right, and its direction indicated the order of report. The results for each group were discussed in terms of asymmetry for rate of processing and rate of decay, and in comparison with our earlier study of word recognition.     

Memory scans based on alternative test stimulus representations

In a search task similar to that used by Sternberg (1966), Ss were presented with one of three alternative representations of a given stimulus and were required to state whether or not that stimulus was present in a previously memorized list. For each type of stimulus representation and each response (positive or negative), reaction time was recorded. Functions relating reaction time to the size of the memorized list were both qualitatively and quantitatively different from those usually obtained with the Sternberg paradigm. In particular, the form of the functions did not correspond to predictions based on an exhaustive scanning process.     

An on site stress workshop for teachers: The creation of a therapeutic group environment

This paper describes an ongoing stress workshop conducted for 5 years in an elementary school. The school was located in an economically deprived area in the Bronx, New York. Similarities and differences between on-site workshops and therapy groups are discussed. The developmental stages of the group and its corresponding issues are analyzed in terms of group process, transference, and resistance. Illustrative vignettes are presented. The positive effects of group dynamic and group therapy interventions on the participating group as well as on nongroup personnel is demonstrated. Suggestions for adapting group therapy methods in school settings are also presented.This paper was presented as a poster at the Annual Conference of the American Group Psychotherapy Association held in Atlanta, Georgia, February 1995.     

Gender differences in patterns of emotional distress following heart transplantation

The study provides the first empirical evaluation of gender differences in psychological symptomatology and DSM-III-R major depressive disorder (MDD) across the first year following heart transplantation. An important goal was to identify physical health-related and psychosocial factors that could account for, or mediate, any association between gender and psychological distress. The sample for the present analyses was drawn from a larger cohort of 172 heart recipients and included all 28 women in the cohort plus 118 men who were matched demographically with the group of women. Detailed patient assessments were completed at 2, 7, and 12 months posttransplant. As expected, women's symptom levels were consistently higher than men's. However, while men's symptom levels in all areas declined with time posttransplant, women's distress in the area of depression initially improved but then worsened by the 12-month assessment. The distribution of episodes of MDD showed a temporal pattern of gender differences similar to that of depressive symptoms. The most important mediators of the gender-depression relationship were factors related to early posttransplant daily functional limitations: women reported more impairments in daily activities. Higher levels of such impairments, in turn, predicted subsequently higher depression levels by 12 months posttransplant. Several additional variables pertaining to transplant-related concerns and a low sense of personal mastery—while not serving as mediators—exerted their own independent effects on 12-month depression levels. The findings are relevant to the tailoring of educational and clinical interventions to the individual needs of women and men who receive heart transplants.Roberta G. Simmons, Ph.D., died on February 15, 1993, during data collection for this paper.     

Cognitive representations of functional interactions with objects

Two studies addressed people’s knowledge about the movements underlying functional interactions with objects, when the interactions were described by simple verbal labels expressing environmental goals. In Experiment 1, subjects rated each action with respect to six dimensions: which portion of the limb moved, distance moved, forcefulness, effectors involved, size of the contact surface, and resemblance to grasp. Ratings were systematic and fell on two distinct underlying factors related to limb movement and effector (usually the hand) configuration. In Experiment 2, subjects sorted a subset of the actions by similarity of movement. Clustering and multidimensional scaling solutions indicated that the six initial dimensions contributed to similarity judgments, along with additional parameters. The results support the existence of cognitively accessible, but still relatively specific, representations of functional actions, with potential implications for motor and memory performance.     

Haptic identification of objects and their depictions

Haptic identification of real objects is superior to that of raised two-dimensional (2-D) depictions. Three explanations of real-object superiority were investigated: contribution of material information, contribution of 3-D shape and size, and greater potential for integration across the fingers. In Experiment 1, subjects, while wearing gloves that gently attenuated material information, haptically identified real objects that provided reduced cues to compliance, mass, and part motion. The gloves permitted exploration with free hand movement, a single outstretched finger, or five outstretched fingers. Performance decreased over these three conditions but was superior to identification of pictures of the same objects in all cases, indicating the contribution of 3-D structure and integration across the fingers. Picture performance was also better with five fingers than with one. In Experiment 2, the subjects wore open-fingered gloves, which provided them with material information. Consequently, the effect of type of exploration was substantially reduced but not eliminated. Material compensates somewhat for limited access to object structure but is not the primary basis for haptic object identification.     

Identifying objects by touch: An “expert system”

How good are we at recognizing objects by touch? Intuition may suggest that the haptic system is a poor recognition device, and previous research with nonsense shapes and tangible-graphics displays supports this opinion. We argue that the recognition capabilities of touch are best assessed with three-dimensional, familiar objects. The present study provides a baseline measure of recognition under those circumstances, and it indicates that haptic object recognition can be both rapid and accurate.     

The attribute priming effect in patients with Alzheimer's disease

Experiments with semantic priming (SP) paradigms have documented early hypopriming in patients with AD when concepts are used as primes and attribute concept features as targets, suggesting that concept attributes are vulnerable to damage very early in the disease course. The aims of this study were to confirm early priming reduction in the attribute condition in patients with AD and to determine which of several semantic indexes (such as the level of distinctiveness, correlation or feature dominance of concept features) best predicts the priming effect size in AD. We administered an SP attribute condition paradigm to 20 mildly demented patients with AD and to 10 NCs. We used concept–attribute pairs for which normative data of semantic indexes relative to both concept primes (i.e., number, type, mean level of dominance, distinctiveness and correlation of features constituting the concepts) and target features (i.e., level of feature dominance, correlation and distinctiveness) were available. Results showed that compared to NCs, the AD group obtained very reduced priming facilitation. Furthermore, the item regression analyses showed that the priming decrement in the AD group was predicted by the feature dominance of the target in the related pairs; that is, the lower the target feature dominance, the lower the priming effect elicited. These results confirmed hypopriming in the attribute condition from the very early phase of AD and support the view that attributes which are more salient for the identification of a given concept are also those most resistant to semantic memory degradation in AD pathology.