Effects of ontogeny on performance of rats in a novel object-recognition task

The current experiment investigated ontogenetic forgetting on a novel object-recognition task similar to that of Besheer and Bevins. 18-day-old pups (n = 49) and adult (n = 29) rats were tested at two retention intervals (1 min. or 120 min.). By employing exclusion criteria which demanded minimum amounts of object exploration at training and test, the performance of 18-day-old pups but not that of adults was significantly impaired at 120 min. relative to 1 min. Analysis indicated that the ontogeny of the learning and memory measured in novel object recognition follows a developmental trend similar to that of other forms of learning, with older animals remembering more and thus performing better than younger animals. Unfortunately, given the extreme variability inherent to the task and large N necessary to achieve significance, the use of this task in studies of learning, memory, and development is discouraged.     

Marital status and the risk of suicide: experience from England and Wales, 1982-1996

This analysis examined suicide rates by age, sex, and marital status in England and Wales for the period 1982-1996. Never married, widowed, and divorced people had higher rates of suicide than those who were married, for both sexes. Among the widowed ages 20-39 years, both sexes had the highest rate, and the rate decreased with age. The suicide rate for divorced people was similar to those who had never married, except for the younger group ages 20-29 years. The male:female ratios for the relative suicide risk for never married, widowed, and divorced to married for both sexes were statistically significantly different for older adults. The decrease in suicide rates observed for the period 1982-1996 in England and Wales was mainly attributable to the reduction of suicide rates among the widowed and divorced.     

Negative compatibility or object updating? A cautionary tale of mask-dependent priming

The negative compatibility effect (NCE) is the surprising result that visual targets that follow a brief prime stimulus and a mask can be identified more rapidly when they are opposite rather than identical to the prime. In a recent article in this journal, S. T. Klapp and L. B. Hinkley (2002) proposed that this reflected a competition between inhibitory unconscious processes and excitatory conscious processes. The authors of the current article report 7 experiments with results countering this theory and propose an alternative account within the framework of object substitution masking. In this account, the NCE reflects the updating of perceptual objects, including their links to responses closely associated with those objects.     

Temporal coding in conditioned inhibition: analysis of associative structure of inhibition

Two experiments with rats as subjects were conducted to investigate the associative structure of temporal control of conditioned inhibition through posttraining manipulation of the training excitor-unconditioned stimulus (US) temporal relationship. Experiment 1 found that following simultaneous Pavlovian inhibition training (i.e., A --> US/XA-no US) in which a conditioned stimulus (CS A) was established as a delay excitor, maximal inhibition was observed on a summation test when CS X was compounded with a delay transfer CS. Furthermore, posttraining shifts in the A-US temporal relationship from delay to trace resulted in maximal inhibition of a trace transfer CS. Experiment 2 found complementary results to Experiment 1 with an A-US posttraining shift from serial to simultaneous. These results suggest that temporal control of inhibition is mediated by the training excitor-US temporal relationship.     

Form-priming effects in nonword naming

Form-priming effects from sublexical (syllabic or segmental) primes in masked priming can be accounted for in two ways. One is the sublexical pre-activation view according to which segments are pre-activated by the prime, and at the time the form-related target is to be produced, retrieval/assembly of those pre-activated segments is faster compared to an unrelated situation. However, it has also been argued that form-priming effects from sublexical primes might be due to lexical pre-activation. When the sublexical prime is presented, it activates all form-related words (i.e., cohorts) in the lexicon, necessarily including the form-related target, which-as a consequence-is produced faster than in the unrelated case. Note, however, that this lexical pre-activation account makes previous pre-lexical activation of segments necessary. This study reports a nonword naming experiment to investigate whether or not sublexical pre-activation is involved in masked form priming with sublexical primes. The results demonstrated a priming effect suggesting a nonlexical effect. However, this does not exclude an additional lexical component in form priming.     

Neural synergy between kinetic vision and touch

Ambiguous visual information often produces unstable visual perception. In four psychophysical experiments, we found that unambiguous tactile information about the direction of rotation of a globe whose three-dimensional structure is ambiguous significantly influences visual perception of the globe. This disambiguation of vision by touch occurs only when the two modalities are stimulated concurrently, however. Using functional magnetic resonance imaging, we discovered that touching the rotating globe, even when not looking at it, reliably activates the middle temporal visual area (MT+), a brain region commonly thought to be crucially involved in registering structure from motion. Considered together, our results show that the brain draws on somatosensory information to resolve visual conflict.     

Borderline psychopathology in the first-degree relatives of borderline and axis II comparison probands

The purpose of this study was to assess the prevalence of each of the nine DSM criteria for borderline personality disorder and the prevalence of the disorder itself in the first-degree relatives of borderline probands and Axis II comparison subjects. Four hundred and forty-five inpatients were interviewed about familial borderline psychopathology using the Revised Family History Questionnaire--a semistructured interview of demonstrated reliability. Of these 445 subjects, 341 met both DIB-R and DSM-III-R criteria for BPD and 104 met DSM-III-R criteria for another type of personality disorder (and neither criteria set for BPD). The psychopathology of 1,580 first-degree relatives of borderline probands and 472 relatives of Axis II comparison subjects was assessed. Both DSM-III-R and DSM-IV BPD were found to be more common among the relatives of borderline than Axis II comparison probands. However, five of the criteria for BPD (inappropriate anger, affective instability, paranoia/dissociation, general impulsivity, and intense, unstable relationships) and all four sectors of borderline psychopathology (affect, cognition, impulsivity, and interpersonal relationships) were found to be both more common and discriminating than the BPD diagnosis itself. Taken together, the results of this study suggest that the subsyndromal phenomenology of BPD may be more common than the borderline diagnosis itself.     

Project Trust: breaking down barriers between middle school children

This paper analyzes the success of a camp retreat weekend called Project Trust involving middle school students and teachers. The goal of the camp is to break down barriers between cliques identified as active in the school. The camp focuses on building team relationships across clique membership and incorporates elements of peace education and conflict resolution. A treatment group (campers) and comparison group (noncampers) were administered an adaptation of the Bogardus Social Distance Test and the Piers-Harris Children's Self-Concept Scale before and after the camp. Attendance was found to lower social distance scores for nine of the ten groups/cliques. Campers also had higher self-concept scores after the retreat.     

A holistic account of the own-race effect in face recognition: evidence from a cross-cultural study

A robust finding in the cross-cultural research is that people's memories for faces of their own race are superior to their memories for other-race faces. However, the mechanisms underlying the own-race effect have not been well defined. In this study, a holistic explanation was examined in which Caucasian and Asian participants were asked to recognize features of Caucasian and Asian faces presented in isolation and in the whole face. The main finding was that Caucasian participants recognized own-race faces more holistically than Asian faces whereas Asian participants demonstrated holistic recognition for both own-race and other-race faces. The differences in holistic recognition between Caucasian and Asian participants mirrored differences in their relative experience with own-race and other-race faces. These results suggest that the own-race effect may arise from the holistic recognition of faces from a highly familiar racial group.