The present study examines changes in a variety of oculomotoric variables as a function of increasing sleepiness in 129 participants, who have been passed through a broad range of subjective alertness. Up to now, spontaneous eye blinks are the most promising biosignal for in-car sleepiness warnings. Reviewing the current literature on eye movements and fatigue, experimental data are provided including additional indicative oculomotoric parameters; inter-individual differences in the experiments were also assessed. Here, self-rated alertness decreased over six steps on average and proved itself a reliable measurement. Regarding oculomotoric parameters, blink duration, delay of lid reopening, blink interval and standardised lid closure speed were identified as the best indicators of subjective as well as objective sleepiness. Saccadic parameters and fixation durations also showed specific changes with increasing sleepiness. Substantial inter-individual differences in all of these variables were illustrated. Oculomotoric parameters were linked to three different components of sleepiness while driving: a) deactivation; b) decreasing attention, resulting in disinhibition of spontaneous blinks and reflexive saccades; c) increasing attempts of self-activation. Finally, implications for the development of drowsiness detection devices were discussed.

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This study investigates the influence of extensive bimanual training in professional musicians on the incidence of handedness in the most basic form of right-handedness (RH) and non-right-handedness (NRH), according to Annett's "right shift theory". The lateralisation coefficients (LCs) of a total sample of 128 bimanually performing music students were calculated for speed, regularity, and fatigue of tapping by using the speed tapping paradigm. Additionally, the accumulated amount of practice was recorded by means of retrospective interviews. The proportion of designated right-handers (dRH) and non-right-handers (dNRH) in hand performance was identified by binary logistic regression from LCs. A proportion of 30.8% designated NRH in the group of musicians was found, while in the control group of non-musicians (matched for age range) a proportion of 21.7% designated NRH was observed. Incidence of dNRH was higher in string players (35.6%) than in pianists (27.1%). As an effect of the extensive training of the left hand, tapping regularity increased and tapping fatigue decreased among those participants who evidenced an increased amount of accumulated practice time on the instrument. However, speed difference between hands (as indicated by LCs) remained uninfluenced by bimanual training. This finding is in contrast to those of Jancke, Schlaug, and Steinmetz (1997). Finally, our study provides a more reliable (statistical) classification as an external criterion for future genetic analyses of handedness.

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Two studies investigate the influence of handedness on a musical performance. In Experiment 1 we compared designated non-right-handed (dNRH) and designated right-handed (dRH) string and piano players performing in the (non-inverted) standard playing position with respect to (1) performancerelated variables (e.g., musical expression) and (2) health-related variables (e.g., discomfort). The 47 professional instrumentalists (pianists: n = 23, string players: n = 24) were classified for handedness (performance handedness) and participated in a survey study on sensorimotor skills and their sense of well-being at the instrument. In Experiment 2, we tested for differences in sensorimotor performance of both hands in right-and left-handed pianists: 19 professional pianists (music students) were classified for handedness (preference handedness). Participants performed scale playing. In Experiment 1 no evidence was found for a performance-related or well-being-related disadvantage in dNRH instrumentalists playing in the standard position. In Experiment 2 temporal sensorimotor precision in the right hand was superior to that of the left hand in both right-and lefthanded pianists. We conclude that professional musicians adapt to the standard playing position regardless of their objective handedness. However, it cannot be ruled out that a subgroup of dNRH instrumentalists subjectively feel constricted when playing in the standard position.