Qualitative differences in tactuo-spatial motor learning by left-handers.

Tactuo-spatial performance was studied as a function of subject handedness and hand employed in learning and transfer. Seventy-eight dextral and 75 sinistral blindfolded subjects learned a finger-maze with either dominant or nondominant hand. Transfer to the untrained hand was assessed with either an identical or a mirror-image version of the maze. Left hand acquisition required fewer trials; latencies were shorter when the dominant hand was used. All dextrals and those sinistral subjects who used the right hand in acquisition showed superior transfer to the identical maze. Sinistral subjects who used the left hand in acquisition demonstrated facilitated transfer to the mirror image maze. Results are suggested to provide evidence of two qualitatively different hemispheric strategies for encoding tactuo-spatial information.

Patterns of self-reported drinking and driving in Michigan.

We analyzed a statewide telephone survey of Michigan adults to determine patterns of self-reported drinking and driving. The estimated prevalence of drinking and driving was 13.5 percent for men and 2.9 percent for women; the highest prevalence was among 18- to 24-year-old men (32 percent). Based on these estimates, over half a million Michigan adults drank and drove on over one million occasions during the month preceding the survey. Most drinking drivers (93 percent) reported binge drinking, yet 70 percent of them otherwise reported only moderate routine alcohol consumption, that is, they consumed fewer than 14 drinks a week on average. Because we were concerned about the validity of self-reports, we compared the patterns of self-reported alcohol use with the patterns of alcohol-related motor vehicle crashes. The pattern of self-reported drinking and driving (using age-, sex-, and region-specific estimates) was highly correlated with the pattern of injury in alcohol-related crashes (r = .96; p less than .0001). Self-reported patterns of alcohol use may be used to identify persons at highest risk for being injured or dying in a motor vehicle crash.

Analyses of feeding lateralization in the small-eared bushbaby (Otolemur garnettii): a comparison with the ring-tailed lemur (Lemur catta).

Feeding related lateralization was examined in a population of 23 small-eared bushbabies (Otolemur garnettii). The three measures used to determine lateralization were food reaching, holding, and manipulation. Sex and age differences were found, with adult females showing a strong right bias and adult males a left bias. Juvenile males were weakly lateralized and less consistent across measures than adult animals. The use of standard scores to assess lateralization allowed species comparisons to be made. The results of this study were compared with results from a previous study on lateralization in the ring-tailed lemur (Lemur catta). Species comparisons found sex differences to be a stronger factor in lateralization than species differences.

Handedness as a function of sex and age in a large population of Lemur.

A population of 194 lemurs (Lemur spp.), 116 males and 78 females, from 1 to 30 years of age, was assessed for lateralized hand use in simple food reaching with a minimum of 100 reaches per animal. A hand preference was present in 80% of the population with a bias for use of the left hand that was most characteristic of male lemurs and young lemurs. The results confirm the presence of lateralization in prosimians, and we interpret the sex and age differences in relation to current theories of neural lateralization.

Scopolamine suppresses both locomotion and object contact in a free-exploration situation.

It was recently reported by Buhot et al. that presession cholinergic disruption with scopolamine decreases time spent in proximity to novel objects while increasing locomotor behavior. Male Long-Evans rats (Rattus norvegicus, 80 days old) were given low-light access to an arena containing objects but were not forced to remain in the arena. On day 1, each subject was injected with saline (SAL). This session was used for familiarization with the apparatus and procedure. On days 2 and 3, four groups were given saline (SAL) or scopolamine (SCO, 1 mg/kg or 0.25 mg/kg), resulting in SAL-SAL, SAL-SCO, SCO-SAL, and SCO-SCO groups. Videotapes of these sessions were scored according to a standard protocol that allows separate quantification of locomotion, general activity, and object interaction behaviors. Scopolamine suppressed object investigation (both gross contact measures and indices of interaction character) whenever present. In contrast to Buhot et al. (using a forced-exploration situation), in this free-exploration context SCO also suppressed locomotor behavior. This study supports the conclusion that anticholinergics impair information gathering instead of affecting memory directly, which calls into question memory-related explanations of cholinergic treatments.

Health promotion data for state health departments: telephone versus in-person survey estimates of smoking and alcohol use.

Abstract During 1988, more than 40 state health departments conducted telephone surveys to obtain state-specific population estimates of the prevalence of adult health behaviors and health practices. However, the comparability of estimates obtained from these telephone surveys with more expensive in-person surveys has not been assessed in an applied setting. This study compared the prevalence estimates of smoking and binge drinking obtained from a telephone survey (N = 1,492) with an in-person survey (N = 2,802) which were conducted by the state of Michigan during 1982-1983. Although the standard errors for the differences in the estimates for the two surveys were relatively large, the actual differences were consistently small within most age-, sex-, and education-specific groups. Despite certain limitations, telephone surveys provide a reasonable alternative to in-person surveys for estimating the prevalence of health behaviors. The data obtained from these surveys are being used to set state health objectives, to plan state-wide health promotion programs, and to support public health legislation.

Hand preferences and whole (Galago senegalensis).

The hand preferences in prey capture and whole-body turning biases after prey capture were assessed in 10 lesser bushbabies (Galago senegalensis) in 8 conditions designed to manipulate posture, visibility of prey and angle of reaching. Each subject received 60 trials in each test condition for a total of 480 trials. Seven subjects had a left-hand preference in food reaching, three right and none were ambipreferent. Eight subjects had a left whole-body turning bias, one right and one had no bias. No correlation was found between reach preference and turning bias. Bipedal posture facilitated the use of the dominant hand, whereas other manipulated conditions did not have a significant effect on hand use. A neuraxial arousal system is postulated as mediator of the bipedal effect on hand use.