Investigating the Efficacy of the Hand Selection Complexity Task Across the Lifespan

Abstract

There is inconsistent evidence demonstrating a relationship between task complexity and hand preference. However, analyzing the point at which task complexity overrides the decision to demonstrate a biomechanically efficient movement can enable complexity to be quantified. Young children (ages 3–7), adolescents (ages 8–12), young adults (ages 18–25), and older adults (ages 65+) performed a newly developed Hand Selection Complexity Task (HSCT) and completed the Waterloo Handedness Questionnaire (WHQ). The HSCT included a reciprocal Fitts’ tapping task performed in the contralateral space (i.e., same side as preferred hand), followed by ipsilateral space (i.e., opposite side of preferred hand). An alternating contralateral-ipsilateral pattern enabled the participant to progress through six levels of difficulty in three conditions (manipulating target amplitude, width, and combined factors). As participants were free to perform with whichever hand (i.e., preferred, non-preferred) they deemed most appropriate, the level of difficulty where a hand switch occurred was identified. HSCT completion time and error scores were also computed. Findings revealed age to be a significant predictor of dependent measures when considering significant effects and interactions. Combined with the covariate WHQ score as a significant predictor of HSCT time and errors (in some, but not all cases), it can be argued that age-related effects reflect the development of handedness, and changes in strength of handedness across the lifespan. Together, findings suggest that task complexity plays an important role in hand selection when performing a task of increasing difficulty. It appears that task complexity will take precedent over object proximity and biomechanical efficiency, at a certain point, in order to complete the movement with the preferred hand. This point ultimately changes throughout the lifespan.

How far will you go before switching hands? Handedness on the long pegboard across the lifespan

“…As displayed in Table 2 and Figure 3, young children demonstrated marked variability and performed generally slower on the long pegboard compared to young adults, and to a lesser extent, older children and older adults who performed the task with a similar speed. The performance of young children is consistent with results of the Hand Selection Complexity Task (Williams et al, 2019).…”

“…The current research included the same 80 participants (Male [M] = 31, Female [F] = 49) as Williams et al (2019). Typically developing children ages 4‐ to 7‐years‐old ( n = 17, mean age = 5.46, M = 12, F = 5, 12 right‐handed and 5 left‐handed), and ages 8‐ to 12‐years‐old ( n = 31, mean age = 10.03 years, M = 10, F = 21, 28 right‐handed and 3 left‐handed) were recruited from a summer camp at a university in southern Ontario and a local childhood development centre.…”

“…First, descriptive statistics were computed for the WHQ (Table 1) and long pegboard (Table 2). Consistent with previous work (Williams et al, 2019), Generalized Estimating Equations (GEE; Liang & Zeger, 1986) were performed to examine average time per hole, average switch point, and average number of errors. Start hand (i.e., start with left hand and switch to right hand; start with right hand and switch to left hand) was included as a factor.…”

“…Studies have also compared handedness across the lifespan, to identify similarities and differences in children, young adults, and older adults. Recently, Williams et al (2019) had young children (ages 4–7 years), older children (ages 8–12 years), young adults (ages 18–25 years), and older adults (ages 70+ years) complete a hand selection complexity task, which involves a reciprocal Fitts’ tapping task performed by alternating between contralateral and ipsilateral space. Six levels of difficulty were incorporated through manipulations of target amplitude, target width, and both factors combined.…”

“…To garner a more comprehensive perspective of hand switching and handedness across the lifespan, the current research implemented the long pegboard task with the same group of participants. Unlike the Fitts‐based (Fitts, 1954) hand selection complexity task (Williams et al, 2019), the long pegboard asks participants to make awkward unimanual movements with one hand. The nature of the hand switch is inherently different (i.e., speed‐accuracy trade‐off vs. degree of comfort in object manipulation); therefore, offering unique insights to complement existing literature on the developmental progression of handedness.…”