Is object texture a constraint on human prehension?: kinematic evidence

The present experiment determined whether object texture influenced the transport and grasp components of human prehension. Infrared markers placed on the index finger, thumb, and wrist were recorded using a WATSMART system. The test objects were cylindrical dowels (103 mm high, 25 mm diameter, and 150 g in weight) of various surface materials (plain metal, coated with Vaseline, and covered with coarse sandpaper). Only temporal kinematic measures were affected by texture: Movement time (ms), time after peak deceleration (ms), percentages of movement time following maximum aperture, velocity, and deceleration were all significantly greater for the slippery dowel than the normal and rough dowels. Results indicated that the increased time associated with the slippery dowel could be explained entirely by increased time between contact with the dowel and dowel lift. Thus, these results are like those of Weir, MacKenzie, Marteniuk, Cargoe, and Frazer (1991), in which object weight was shown not to affect the free-motion phase, which includes the transport and grasp components of prehension. It appears that intrinsic object properties like weight and texture affect only the finger-object interaction phase of prehension; subsequent research is needed to dissociate inertial and surface friction effects while in contact with objects     

The Effects of Measurement Strategy on Attributions for Marital Problems and Behaviors1

The present study examined the relation of attributions for spouse behaviors, attributions for global conjugal conflict, and marital adjustment. The sample consisted of 74 French-Canadian couples who completed the Marital Attribution Style Questionnaire, the Conflict Rating Scale, and the Dyadic Adjustment Scale. Results showed that the relation between attribution and marital satisfaction is stable across culture. In addition, specific and general attribution measures were low to moderately correlated. However, multiple regression analyses demonstrated that attributions for global conjugal conflict entered the regression equations more often than attributions for hypothetical spouse behaviors. These findings suggest that the comparability of marital attribution measures should not be taken for granted. The need to develop standardized measures is underlined.     

Dynamic role of social support in the link between chronic stress and psychological distress.

How a chronic environmental stressor can interfere with the buffering effects of social support by eroding social support was analyzed in this prospective, longitudinal study. A classic buffering effect of support was found after 2 months of exposure to the stressor, household crowding. Crowded residents with low perceived support had greater increases in psychological distress than did crowded residents with high perceived support. However, after 8 months exposure the buffering effect disappeared. Moreover, greater crowding had become directly associated with lower support, which in turn was associated with greater increases in psychological distress. All analyses controlled for prior distress. Under some types of chronic stress, the buffering effects of social support may be short-lived because the stressor eventually erodes social support.     

Test of structural relationships within a proposed exercise and self-esteem model

This study tested structural relationships within a model proposed to explain the manner in which self-esteem changes are associated with exercise experiences. As initially assessed by self-efficacies (EFFs) specific to physical tasks within a training program, we postulated that competence can generalize to feelings of global self-esteem (SE) through an intervening construct of perceived physical competence (PC). Three measures of EFF and two each of PC and SE were administered to 145 people in their mid- to late adulthood. Confirmatory factor analysis examined orthogonal and oblique versions of three measurement models and identified three distinct but correlated factors, each assessed by its hypothesized indicators. Alternative structural equation models were specified and tested using both normal and nonnormal estimation procedures. The proposed model provided the most parsimonious fit and explained 29% of the variance in SE. Confirmation of its structural relationships provides preliminary validity for model use in examining the manner in which exercise experiences influence levels of self-perception.     

Courtesy stigma: the social implications of associating with a gay person

We investigated the operation of courtesy stigma with American male college students who reacted to a fictitious male student described as gay, rooming by choice with a gay male student, involuntarily assigned to room with a gay, or rooming with a male heterosexual. Among respondents who expressed strong intolerance of gays, the voluntary associate of a gay was perceived as having homosexual tendencies and as possessing the same stereotyped personality traits attributed to a gay. No such courtesy stigma was attached to the involuntary associate of a gay by these respondents. Relatively tolerant respondents engaged in no courtesy stigmatization at all. Thus, courtesy stigmatization occurred only under circumscribed conditions and appeared to depend more on the tendency of highly intolerant individuals to infer that a male student who apparently liked a gay individual was himself gay than on a motivation to maintain cognitive consistency.     

The MCMI-II depression scales: do they assist in the differential prediction of depressive disorders?

This study examined the diagnostic efficiency of the Millon Clinical Multiaxial Inventory-II (MCMI-II) Major Depression (CC) and Dysthymia (D) scales for the differential prediction of unipolar depressive disorders. The MCMI-II was administered to 109 inpatients at a large private psychiatric hospital in the Midwest. All patients had a primary Axis I diagnosis of a depressive disorder, given at discharge by the attending psychiatrists. When CC scores were compared to clinician diagnoses, results indicated that the sensitivity of the CC scale was improved over what had previously been reported for studies involving the MCMI-I CC scale. However, overall, the D scale functioned slightly better as a predictor of major depression than did the CC scale. One likely factor in explaining this finding is that the CC scale contains very few items assessing vegetative/somatic symptomatology, which are the critical factors in distinguishing major depression from other unipolar depressive disorders.     

Equivalence of Peabody Picture Vocabulary Test--Revised, forms L and M for children with acquired immune deficiency syndrome (AIDS)

The purpose of this preliminary investigation was to assess the equivalence of Forms L and M of the Peabody Picture Vocabulary Test--Revised for a sample of 15 Hispanic and 12 black children diagnosed as having Acquired Immune Deficiency Syndrome (AIDS). The children (15 boys, 12 girls) were administered PPVT-R Forms L and M in counterbalanced order and in immediate succession. The coefficient of equivalence, r, was .77 and significant. Influential factors, such as the behavioral manifestations of AIDS, are discussed. Limitations of the study are included. Research should focus on the long- and short-term stability of the test for these children as they are evaluated repetitively.     

Formant frequency characteristics of children, young adult, and aged female speakers

Previous literature indicates that a difference may exist between formant frequencies (F1 and F2) of children, young adult, and elderly speakers. The purpose of this study was to compare F1 and F2 of 3 young, 6 young adult, and 3 elderly female speakers for the /i/, /ae/, /u/, and /a/ vowels. Analysis indicates a trend towards vowel reduction across the life span. These findings support previous research regarding age-associated acoustic changes as well as support for the possible anatomical and physiological alterations which may influence such changes.     

Developmental perspectives on the localization and detection of auditory signals

Responsiveness of 1-, 3-, and 5-year-old children and adults to octave-band noises at .4 and 10 kHz was assessed with a go/no-go version of visual reinforcement audiometry (VRA) (Moore, Thompson, & Thompson, 1975) and a two-alternative, forced-choice version (Suzuki & Ogiba, 1961; Trehub, Schneider, & Endman, 1980). Infants performed better on the two-alternative, forced-choice version in quiet and in noisy backgrounds, and adults performed better on the two-alternative, forced-choice version in quiet but not in noisy backgrounds. Performance on the two tasks was essentially equivalent for 3- and 5-year-old children. Superior performance on two-alternative VRA over go/no-go may be due to lesser cognitive demands in the case of infants and to the engagement of superior decision strategies in the case of adults.