Pamela J. Bryden

A new method of administering the Grooved Pegboard Test: performance as a function of handedness and sex.

The purpose of the present study was twofold: first to examine the influences of sex and handedness on manual performance on the Grooved Pegboard Test; and secondly to provide normative data for two versions (Place and Remove tasks) of the Grooved Pegboard Test, as previous work (Bryden & Roy, 1999) had suggested that the Remove task of the Grooved pegboard may provide a purer measure of motor speed of the two hands than the standard administration of the Grooved Pegboard Test. One hundred and fifty-three (47 males and 106 females) participants completed the Grooved Pegboard Test. Individuals performed the standard version of the Grooved Pegboard Test (Place task) and a novel version of the test (Remove task). In the standard version, participants were timed on their speed for placing the pegs, while in the novel version they were timed on their speed for removing the pegs. Results confirmed previously noted hand and sex differences in the Place task of the Grooved Pegboard Test, as well as the lack of effect of handedness on performance (Bornstein, 1995; Ruff & Parker, 1993). Significant performance differences between the hands were also noted for the Remove task. Findings also indicated that the Remove task was sensitive to sex and handedness effects.

Using hand performance measures to predict handedness.

Handedness is defined by the individuals preference to use one hand predominately for unimanual tasks and the ability to perform these tasks more efficiently with one hand (Corey, Hurley, & Foundas, 2001). It is important to use performance variables to measure handedness because they are more objective than traditional hand preference questionnaires (Bryden, Pryde, & Roy, 2000a). The current study develops a predictive model of handedness as measured by the Waterloo Handedness Questionnaire (WHQ) using several performance indicators of handedness. A total of 120 individuals (60 right-handers and 60 left-handers) were asked to complete four performance-based tasks: the Grooved Pegboard (GP), the Annett pegboard (AP), finger tapping (FT), and grip strength (GS) as well as an observational measure of preference, the Wathand Box Test (WBT). Backward linear regression analysis showed that the Wathand Box measure and the laterality quotients for several performance measures (GP place, AP, and FT) combined to act as the most accurate predictors of hand preference. The predictive model of handedness developed is as follows: WHQ = -2.760- – 0.667(GP place) + 0.809(FT) + 0.234(WBT) – 0.748(AP) with an explained variance of 0.836. These results illustrate, as Corey et al. (2001) suggested, that the best predictive model of handedness combines preference measures and several performance measures that tap into different elements of motor performance. By developing this model, it is possible to get an accurate measure of handedness using objective measures.

Hand preference, performance abilities, and hand selection in children

It is widely know that the pattern of human handedness is such that approximately 90% of the population is right handed with the remainder being left handed, at least in the adult population. What is less well understood is how handedness develops and at what age adult-like handedness patterns emerge. Quantified in terms of both preference and performance, a plethora of different behavioral assessments are currently in use with both children and adults. Handedness questionnaires are commonly used; however, these possess inherent limitations, considering their subjective nature. Hand performance measures have also been implemented; however, such tasks appear to measure different components of handedness. In addition to these traditional measures, handedness has been successfully assessed through observation of hand selection in reaching, which has proven to be a unique and effective manner in understanding the development of handedness in children. Research over the past several decades has demonstrated that young children display weak, inconsistent hand preference tendencies and are slower with both hands. Performance differences between the hands are larger for young children, and consistency improves with age. However, there remains some controversy surrounding the age at which hand preference and hand performance abilities can be considered fully developed. The following paper will provide a review of the literature pertaining to hand preference, performance abilities and hand selection in children in an attempt to ascertain the age at which adult-like patterns of hand preference and performance emerge.

Handedness and health: An examination of the association between different handedness classifications and health disorders

The current study investigated the incidence of various health disorders in a sample population of undergraduate students, using a 25-item hand preference questionnaire. Analysis revealed significant differences existed in the incidence of several health disorders as a function of handedness: however, these differences depended on how hand preference was defined. Overall, the results showed that non-right-handed participants (i.e., those individuals with left-handed, ambidextrous, or inconsistent hand preferences) were significantly more likely to report specific health disorders (such as high blood pressure and epilepsy) than right-handed participants. The findings provide support for the argument that left-handedness, or non-right-handedness, is associated with various health disorders. The results are discussed in light of the Geschwind-Behan-Galaburda model of cerebral lateralisation.

Examining gender differences in the health behaviors of Canadian university students

The relationship between lifestyle choices and health outcomes has been an area of interest for many health professionals. Gender differences in these choices have also been an area of scrutiny. Aims: The purpose of the present investigation was to examine gender differences in the health and lifestyle behavioral choices of Canadian university students. Methods: A total of 638 (472 female and 166 male) undergraduate students were evaluated. Results: Males and females differed significantly in their responses to appraisals of general state of health, hours/day engaged in social activities, frequency of drinking alcohol, amount of alcohol consumed per session, total number of sexual partners, number of meals eaten per day, participation in physical activity, completion of annual check-ups with doctor, screening for sexually transmitted diseases (STDs), and hypertension screening. Generally, men engaged in more risky health behaviors than females (e.g. alcohol use). Conclsion: Results are discussed in terms of cultural comparisons to previous research studies evaluating college health behaviors. Suggestions are made for health professionals to incorporate gender differences in behavioral change programmes geared towards improving awareness of the consequences of lifestyle choices.

Reaching patterns across working space: the effects of handedness, task demands, and comfort levels.

Two experiments are reported which examine skill demands, location, and perceived comfort levels for a preferential reaching test with left- and right-handed participants. In Experiment 1, the effect of task demands was examined by having participants perform tasks of varying difficulty with tools (Lift, Pantomime, and Use) that were placed in an array in working space. Preferred hand reaches predominated at the midline and ipsilateral positions, and decreased significantly for contralateral positions, where the frequency of preferred hand reaches increased with task difficulty. In Experiment 2 we developed a new measure (the Comfort Rating Scale) to rate the subjective feeling of comfort for reaching movements. Using the same array of tools and tasks, participants were instructed which hand to use to perform reaching movements, and then rated how the movement felt. The preferred hand was always rated as being comfortable, whereas the non-preferred hand was sensitive to the effects of task demands and tool position. The ratings showed that it was the level of comfort with the non-preferred hand, rather than with the preferred hand, that contributed to the patterns seen on the first study. The Comfort Rating Scale provides new insight into the distribution of reaching movements within working space.

Influences of task complexity, object location, and object type on hand selection in reaching in left and right-handed children and adults.

The effects of task complexity, object location, and object type on reaching behavior were examined. Two hundred ninety-two right-handed and 38 left-handed participants (grouped into five age groups) were asked to pick up or pick up and use objects in different regions of peripersonal space. It was found that individuals used their nonpreferred-hand more often in contralateral space than at the midline position. Using an object resulted in significantly more preferred-hand reaches than picking up an object. Furthermore, task complexity, object location, and object type interacted with each other depending upon age group and hand preference.

Preliminary examination of oral contraceptive use among university-aged females.

The etymology and use of oral contraceptives (OCs) has greatly influenced the sexual practices and social lives (e.g., decisions concerning childbearing, careers) of adolescent and adult women. In addition, OCs have the potential to benefit or harm its users depending upon the utilization practices and characteristics/lifestyle habits of the women consuming them. A 28-item questionnaire was distributed to female students at a university in Central Ontario and examined: (1) socio-demographic information; (2) background information concerning oral contraceptive use (e.g., length of time taking the pill, concerns about pill use, side effects while on the pill); and (3) procedure for taking the pill (e.g. maximizing effectiveness and safety). Preliminary analysis indicated that females may not be equipped with adequate knowledge or receiving the necessary support to practice the most efficacious behaviours surrounding pill use.

Unimanual performance across the age span

The purpose of the current investigation was to examine the age-related changes in the performance of the two hands on the Annett pegboard (Annett, 1970). The current study was part of a large-scale study investigating the development of unimanual and bimanual performance. Three hundred and two right-handed individuals participated in the present study, comprising five different age groups (3-5 year olds, 6 and 7 year olds, 8 and 9 year olds, 10-12 year olds, and 19-24 year olds). All participants completed the Waterloo Handedness Questionnaire and the standard Annett pegboard. Analyses revealed significant overall performance differences between the hands, as expected, where the right hand was significantly faster than the left hand. Additionally, significant performance differences between the hands were noted as a function of age. More specifically, the adults showed a much smaller performance difference between the hands than the other age groups. The results are discussed in light of current theories of the development of hand preference and manual asymmetry.

The Costs of Caring for a Child with an Autism Spectrum Disorder

Background: The primary purpose of this exploratory autism research was to examine the lived experiences of female primary caregivers of children with an autism spectrum disorder (ASD). Methods: Specifically the costs and benefits of the primary caregivers’ experiences were examined through semi-structured one-one-one interviews. The specific focus of this paper was to examine the costs of caring for a child with an ASD, whereby costs did not refer solely to monetary costs, but were related to all aspects of the caregivers’ lives. Interviews were completed with 8 mothers of children that had been formally diagnosed with an ASD. Results: Undoubtedly all family members within the family unit were affected by a child’s diagnosis with ASD as evidenced by the costs revealed by mothers. The subthemes derived from the theme of costs included the following: financial and work costs, costs to the health of family, social costs, and costs to overall family life. The results from this research provide evidence of the challenges associated with caring for a child with an ASD. Conclusions: It is anticipated that the insights provided by these mothers can act as a source of support for others faced with a similar situation. Additionally health care professionals may be able to use the knowledge gained from such qualitative endeavors in order to help parents cope more effectively with their caregiving responsibilities associated with children with ASDs. The mothers within this study are remarkable women that, for the most part, were able to rise above the negatives/costs associated with caring for a child with an ASD and find the silver linings amidst the turmoil. As remarkable as these women are in the daily struggles they face with their children, it is evident that more resources and support are required to assist these women and their families.