Intrahemispheric response competition between vocal and unimanual performance in normal adult human males.

Conducted 4 experiments, using a total of 150 right-handed male undergraduates. Ss balanced a dowel rod vertically on the left and right index finger singly and while simultaneously repeating phrases. With right-handed Ss who had no left-handed relatives, concurrent verbalization shortened right- but not left-handed balancing. Increased phonetic difficulty of the phrases produced an increased decrement on right-handed balancing, but left-handed balancing was unchanged; it also produced more verbalization errors on trials with the right hand, but not with the left. Concurrent verbalization shortened balancing duration with both hands of left handers. Right-handers with left-handed relatives produced variable results. Concurrent humming also selectively interfered with right-handed balancing. It is concluded that the results conform to an interpretation based on intrahemispheric interference between incompatible, simultaneously produced sets of responses. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cerebral lateralization for the processing of spatial coordinates and categories in left-and right-handers

Subjects judged whether a tachistoscopially lateralized drawing was identical or different to a drawing seen immediately before in free vision. The drawings depicted natural objects (e.g. animals). On half of the trials the tachistoscopic drawing presented the same objects but either the categorical or the coordinate spatial relations (according to Kosslyn's definitions [23]) between the objects were transformed. In the first experiment 38 right-handed subjects (half males and half females) were tested. Categorical judgements were faster when the match drawing appeared in the right visual field, whereas coordinate judgements were faster when the match drawing appeared in the left visual field. In the second experiment 26 right-handed and 40 left-handed subjects participated. Almost all the subjects were female. Right-handed subjects replicated the findings of the subjects in the first experiment. However, the LHs did not show any difference in response times between spatial conditions and visual fields. These findings support Kosslyn's hypothesis that the left and right hemispheres are specialized respectively for processing categorical and coordinate spatial relations. Moreover, they also suggest that this lateralization pattern is not typical of left-handers.     

Classroom seating and hypnotic susceptibility.

Conducted 2 experiments to investigate the relations among hypnotic susceptibility (Stanford Hypnotic Susceptibility Scale), lateralization of actual seating behavior, and seating preference. In Exp I, it was found that females who sat on the right side of a classroom were more hypnotically susceptible than females who sat on the left. Males who preferred right-side seating were more susceptible than males with left-side preferences. In Exp II, 55 Ss were randomly assigned to seats to determine whether seating location itself affected responsiveness to hypnosis. No association between lateralization of actual seating and hypnotic susceptibility was found. Replicating Exp I, males who preferred right-side seating were more hypnotically susceptible than males with left-side preferences. Lateralization of seating behavior has been found previously to be a function of hemisphericity. The results of both experiments indicate that lateralization of seating behavior may be used to investigate the relation between hemisphericity and hypnotic susceptibility. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Handedness and approach-avoidance behavior in chipanzees (Pan).

The relationship between hand preference and approach–avoidance behavior was examined in 49 chimpanzees (Pan). Ss were presented with 2 sets of novel objects on 4 consecutive days. The objects were presented for 2 hrs during each session, and latency to touch any object was recorded for each S. Latency scores were then compared for chimpanzees that had been determined to be non-right- or right-handed. Right-handed Ss approached and touched the objects significantly faster than non-right-handed Ss did. In addition, males touched the objects significantly faster than did females. Correlations in approach–avoidance behavior were significant across stimulus sets and days of testing. The overall results support recent theoretical models linking hemispheric specialization with the expression of positive and negative affective behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Uterine position and conditioned taste aversion.

Three experiments investigated the influence of uterine position on the performance of female offspring of female Sprague-Dawley and male Long-Evans rats in a conditioned taste aversion paradigm. 49 females that had males caudal to them in the same uterine horn (MF), 48 females with no caudal males (FF), and 24 males that had occupied a variety of different positions in the uterine horn were examined. Exps I and II confirmed a differential behavioral response by males and females during acquisition and extinction of the conditioned taste aversion. However, no differences were found between MF and FF Ss. In Exp III, in which testosterone was administered to females throughout testing, MF females showed an increased sensitivity to testosterone and a more prolonged rate of extinction than FF females. Exposure to testosterone during prenatal development heightened postnatal responsiveness to testosterone in female Ss. Results are discussed in terms of the organizational and activational effects of testosterone on behavior in a conditioned taste aversion situation. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding of geometric and landmark information in the left and right hemispheres of the avian brain.

Chicks were trained binocularly to find food buried under sawdust in the center of a square enclosure. When tested in an enclosure made larger or smaller in size, binocular and left-eyed chicks searched mainly on the basis of relative distance of the food from the enclosure walls, whereas right-eyed chicks searched on the basis of absolute distance. Moreover, binocular and left-eyed chicks relied mainly on global spatial information (i.e., distances from the walls), whereas right-eyed chicks also used information provided by visual landmarks. These results suggest that the right hemisphere of the avian brain (fed mostly by the left eye) is primarily concerned with encoding of relational spatial information, whereas the left hemisphere (fed mainly by the right eye) is concerned with absolute metric information, possibly as part of an encoding strategy based primarily on local (both spatial and nonspatial) cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental rotation of facial profiles: Age-, sex-, and ability-related differences.

48 adults (mean age 28 yrs 4 mo), 48 8th graders, and 48 4th graders determined what the left–right orientations of rotated facial profiles would be were the profiles upright. There were 24 males and 24 females in each group. Ss were all administered the Raven Standard Progressive Matrices and the Picture Vocabulary and Spatial Ability subtests of the Woodcock-Johnson Psycho-Educational Battery. Results indicate that rate of mental rotation and combined rate of encoding, comparison, and response increased with age. Findings are consistent with a speed–accuracy tradeoff explanation of previous discrepancies in developmental studies of mental rotation. Female Ss' rates of mental rotation were slower on average and more variable than male Ss. Within the entire sample, there was a modest correlation between the ability test scores and both latency and error parameters derived from the rotation task. Only error rate was discriminantly related to spatial ability, however. Patterns of correlations between processing parameters and test scores differed between age groups and, within age groups, between sexes. Mental rotation showed a significant relation to spatial ability only in 4th graders. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in cerebral organization for speech and praxic functions.

A retrospective study on incidence of aphasia and apraxia was done on 143 male (mean age 50.4 yrs) and 73 female (mean age 45.7 yrs) right-handed patients with unilateral lesions of the left cerebral hemisphere and on a subgroup of 81 patients with damage restricted to anterior or posterior regions. Aphasia was proportionally more frequent in males than in females, but this difference was significant only in the larger sample. Moreover, the pattern of speech representation differed between the sexes: Speech disorders and manual apraxia occurred in females more often from damage to the anterior part of the left hemisphere than from posterior damage. This was not true for males. In the 169 Ss with unilateral right-hemisphere damage, the incidence of aphasia was extremely low and did not differentiate the sexes. It is concluded that there are sex differences in the organization of speech and praxis within the left hemisphere and that speech is not simply more bilaterally organized in females than males. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of experimenter modeling, demands for honesty, and initial level of suggestibility on response to "hypnotic" suggestions.

Pretested 180 college students on behavioral (objective) and experiential (subjective) responses to the test suggestions of the Barber Suggestibility Scale. After being exposed to 1 of 3 treatments--E modeling, hypnotic induction, or control--each S was retested on the same scale. Strong demands to give honest experiential reports were administered to 1/2 of the Ss under each treatment. Ss who were exposed to E modeling manifested a greater enhancement in objective responsiveness to test suggestions than control Ss and as much enhancement as Ss who were exposed to hypnotic induction. E modeling was as effective as hypnotic induction in enhancing sujective responsiveness to test suggestions with and without demands for honest reports. Under both the E modeling and hypnotic induction treatments, Ss who had initially manifested a high level of suggestibility (pretest) showed as much enhancement in subjective responsiveness to test suggestions as medium- or low-suggestible Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attitudes towards homosexuality and male and female reactions to homosexual and heterosexual slides.

Investigated the relationship between attitudes toward male and female homosexuality and Ss' reactions to slides of various explicit sexual activities (including homosexuality, lesbianism, heterosexual activity, and group sex). Attitudes toward homosexuality and lesbianism were highly correlated. Saskatchewan males were more antihomosexual than an Ontario sample, supporting the suggestion that there is greater concern with "machismo" among males on the Prairies. 34 male and 31 female undergraduates were divided into those opposed to homosexuality (anti-H) and those not opposed (H-neutral) on the basis of attitude scale scores. While the 4 groups substantially agreed in the relative rating of the slides, anti-H Ss of both sexes rated the slides as more pornographic and evaluated them more negatively than H-neutral Ss. Females rated them more negatively than males, while males rated all but the male themes (male nude, masturbation, homosexual) more sexually arousing than did females. Males reacted more negatively to the male themes than to the comparable female themes. Female Ss showed no such difference. (French summary) (1 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Odor modulation of ventral scent gland marking in the Mongolian gerbil.

In an experiment with 18 male and 18 female Mongolian gerbils, gerbil odors were allowed to accumulate in individual home cages for several months to provide stable olfactory stimuli that might modulate the number of ventral scent gland marks produced by the Ss. Male marking levels for most test conditions were 2–3 times larger than those in females, although, the relative patterns of responsiveness to particular odors were similar in both sexes. The number of scent marks in home cages was significantly smaller than the number obtained in clean cages. Marking levels in the home cages of other Ss were substantially higher than those seen in the test S's own cage and were maximal in the home cages of other males. Behaviorally receptive females marked at significantly higher levels in home, clean, and conspecific cages than did nonreceptive females. Conspecific urine odors, especially those from females, increased marking levels significantly over those obtained in home cages. In males, home cage marking was significantly enhanced by the presence of a female. Both sexes showed significant reductions in marking levels in another's cage if the resident was present. Results suggest that scent-marking like other olfactory guided behaviors and odor preferences, is context-specific. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of 3- to 4-year-olds assessed at home and their interactions in preschool.

Assessed the characteristics of 24 male and 21 female 42-mo-olds in the UK using a semistructured maternal interview concerning behavior at home. Behavior in preschool was recorded by direct observation. The procedures were repeated for 21 of the males and 16 of the females 8 mo later. Results show that many of the characteristics assessed at home were related in a predictable way to behavior in preschool. For example, shy Ss interacted less with peers at 42 mo of age. At 50 mo of age they initiated fewer interactions with adults, but shy males played interactively with peers. Assertive Ss were involved in more interactions and controlled others at 42 mo of age. These Ss showed more interactive play, hostile interactions, and crying at age 50 mo. The characteristics Active, Moody, and Assertive produced at least twice as many significant correlations at 50 mo as at 42 mo of age. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sexual Experiences Survey: Reliability and validity.

Explored the veracity of self-reported sexual experiences as relayed by university students (242 females and 144 males) on a sexual experience survey that was completed once privately and a 2nd time in the presence of an interviewer. The Ss were selected from a group of 4,000 students to represent all degrees of exposure to sexual aggression and sexual victimization. Of the female Ss (mean age 21.3 yrs), 86% were single, 92% were White, and 25% were in each year of college study. Of the male Ss (mean age 21.7 yrs), 89% were single, 87% were White, and 25% were in each year of college study. Female Ss were classified as nonvictimized, sexually coerced, sexually abused, or sexually assaulted. Male Ss were classified as nonsexually aggressive, sexually aggressive, sexually abusive, or sexually assaultive. The Pearson correlation between female Ss' level of victimization (LOV) based on self-report and her LOV based on responses as related to the interviewer was .73. Among the 62 females whose self-reports suggested that they were rape victims, only 2 changed their responses. The LOV correlation between male Ss' responses was .61. Results reveal a tendency for males to deny behaviors during interviews that had been revealed on self-reports. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

P300, handedness, and corpus callosal size: gender, modality, and task

The P300 event-related potential (ERP) was elicited in left- and right-handed young adult male and female subjects (n = 20/group), with auditory and visual stimulus modalities from single-stimulus and oddball tasks. P300 amplitude was larger across all conditions for left- compared to right-handed subjects at anterior and central electrode sites. P300 latency was shorter across all conditions for left- compared to right-handers. Task type did not affect the ERP handedness differences. Male and female subjects demonstrated comparable ERP handedness effects, although smaller P300 components were obtained for males compared to females. When considered in the context of previously reported corpus callosal size differences for left- vs. right-handed and male vs. female participants, the findings suggest that the P300 reflects callosal size and inter-hemispheric transmission efficacy.     

The grammar of action and reversal errors in children's printing.

36 left-handed and 36 right-handed kindergarten children were asked to print after seeing a series of reversible letters and numbers presented individually on slides or flash cards. Regardless of handedness, both groups of Ss found the left–right orientation cues of the same letters and numbers difficult to recall. This challenges a proposal expressed in the "grammar of action" that claims that certain reversal errors in children's printing result from the inappropriate application of the horizontal motor rule, because although left- and right-handed children use this rule, they do so in different ways and therefore should have produced different errors. Another sample of 86 right-handed children from nursery school through Grade 1 was given the same printing task. Findings from this 2nd sample provide an additional challenge to the grammar of action by showing that reversals of the letter N, which are also thought to result from a misapplication of motor rules, decrease in frequency along with reversals of other letters and numbers, instead of increasing as predicted, during the developmental period when the motor rules that are said to be responsible for reversals of this particular letter become more strongly established. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic susceptibility as related to gestalt closure tasks.

Studied the relationship of gestalt closure tasks to hypnotizability (Harvard Group Scale of Hypnotic Susceptibility and Stanford Hypnotic Susceptibility Scale) as a test of the hypothesis that the more highly hypnotizable do better on a task of holistic visuospatial functioning than those less responsive to hypnosis. Several other cognitive tasks were included. Four studies were conducted with 125 male and 106 female high school and college students. In Study I, high hypnotizables scored significantly higher than low hypnotizables on the gestalt closure tasks, but there were no significant correlations between hypnotizability and the other cognitive tasks. In Studies II and III, females showed significant correlations between hypnotic susceptibility and gestalt closure scores. In Study IV, a significant correlation between hypnotic susceptibility and gestalt closure was found for males. Results are consistent with studies of different types of cognitive functioning (hemispheric preference, creativity, attentional distribution, imaginative involvement, and absorption), all indicating differences in cognitive abilities associated with high hypnotizability. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotizability, daydreaming styles, imagery vividness, and absorption: A multidimensional study.

Examined the interrelationships between the following measures: hypnotic susceptibility (Stanford Hypnotic Susceptibility Scale, Forms A and C), imagery vividness (Vividness of Visual Imagery Questionnaire; VVIQ), involvement in everyday imaginative activities (Tellegen Absorption Scale; TAS), and daydreaming styles (28 scales of the Imaginal Processes Inventory). Ss were 56 university students and staff members. Factor analysis produced a factor characterized as a positively vivid and absorptive imagination style. Hypnotic susceptibility, VVIQ, TAS, and positive-affect daydreaming styles all loaded on this factor. Two other factors were a dysphoric daydreaming style and a lack-of-attentional-control style. Stepwise multiple regressions suggested that males and females exhibit different relationships between hypnotic susceptibility and predictor variables. Similar differences were found for the VVIQ and the TAS and their daydreaming-scale predictor variables. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Examiner sex, subject sex, and Rorschach productivity.

Investigated the number of Rorschach responses given by 64 male and female clients to 41 male and female graduate students serving as Es. 2 tests were made of the hypothesis that more responses would be given in the female S-male E situation than in any other sex combination. The hypothesis was supported. When a male E tested both a male and female S, the female gave more responses (p = .02); when the sample included male Es who tested either a male S or female S, female Ss again gave more responses than males (p = .05). No such differential effects were found for female Es with male and female Ss. Results are consistent with R. Rosenthal's (see 41:7, 41:8) findings that the male E-female S situation produces unique results. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in cognitive abilities and brain organization: I. Sex and handedness differences in ability.

Analyzed data on cognitive abilities from 3 samples of normal Ss: (1) 195 undergraduates, (2) 215 18–30 yr old newly married couples, and (3) 122 pairs of monozygotic and dizygotic twins (aged 12–38 yrs). Findings reveal a common Sex by Handedness by Reasoning-Ability interaction: For Ss with above-median reasoning ability, spatial scores of left-handed males were reduced but those of left-handed females were raised, relative to their right-handed counterparts; the opposite pattern was found for Ss with below-median reasoning ability. The dependence of handedness effects on reasoning ability level appears to explain some of the inconsistent findings in the literature. Verbal fluency, perceptual speed, and visual memory also showed sex and handedness effects, which often interacted with level of reasoning ability or other cognitive variables. Results strongly suggest that sex and handedness differences in cognitive ability are partly neurological in origin. Variations in the effects of handedness across levels of reasoning ability (or other abilities) may indicate that different trade-offs among structural, and thus cognitive, characteristics will be found in different subsamples: There may be many kinds of normal brain organization. (French abstract) (98 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ego identity, intimacy, sex role orientation, and gender.

Assessed identity and intimacy in 40 male and 40 female university students, using a semistructured interview and a rating manual. Ss were also administered the Bem Sex-Role Inventory. Results show that for males, identity was related to masculinity and intimacy was related to femininity. For females, identity was also related to masculinity; there were more high-intimacy females than males. While high identity/high intimacy was not contingent on androgyny (as hypothesized), proportionately more androgynous than nonandrogynous Ss were in this category. Results lend support to the hypothesis that it is desirable and beneficial for each sex to integrate aspects of the other gender's sex type. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)