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Caffeine withdrawal
Published in B.S. Gupta, Uma Gupta, Caffeine and Behavior, 2020
Rizzo et al.42 measured the effects of caffeine status on reaction time. Users and nonusers were compared, defined as consumers of five-or-more and one-or-less caffeine-containing beverages per day. Subjects were tested twice per week. Users maintained normal intake for 5 days then 2 days abstinence before testing; nonusers continued unchanged throughout. There were no performance differences between the groups while on caffeine, but users abstaining from caffeine had slowed reaction times. In the Bruce et al.28 study, tapping rate was impaired in the subjects 24 hours into withdrawal, but not 7 days after withdrawal. Caffeine restored the slowed performance. White and associates43 obtained similar results for reaction time. Caffeine improved performance, but the period of abstinence (3 hours) was too short for withdrawal to have set in.
Motor Aspects of Lateralization: Evidence for Evaluation of the Hypotheses of Chapter 8
Published in Robert Miller, Axonal Conduction Time and Human Cerebral Laterality, 2019
A similar study was carried out in deaf persons fluent in American sign language (Corina et al., 1992a). Subjects were asked to tap with one hand and copy in sign language with the other hand the words presented to them visually or auditorily. Tapping in the right hand was more severely impaired by concurrent signing than that in the left hand. No asymmetry in tapping rate was found when the concurrent task involved production of other symbolic or arbitrary gestures of complexity similar to the sign-language signs. The authors conclude that the left hemisphere is truly specialised for language. This conclusion can be questioned, because the sign-language signs may have been subject to far greater practice, with development of more fluent time-structured models than the other gestures. If this is the case, it is an aspect of motor specialisation, rather than language per se which determined the asymmetry in producing ASL.
Caffeine, Mood, and Performance: A Selective Review
Published in Barry D. Smith, Uma Gupta, B.S. Gupta, Caffeine and Activation Theory, 2006
Lorenzo D. Stafford, Jennifer Rusted, Martin R. Yeomans
More recently, several studies have reported an increase in tapping rate with caffeine (Fagan et al., 1988; Riedel et al., 1995; Kaplan et al., 1997; Rees, 1999; Rogers et al., 2005); however, a large number of studies have found no effect (Bruce, Scott, Lader, & Marks, 1986; Lieberman et al., 1987a; Rogers & Derncourt, 1998; Robelin & Rogers, 1998). Thus, it appears that caffeine can enhance motor response rate, but that the effect is small and therefore hard to detect. A number of factors could explain some of these differences in results and these are explored later.
Effect of Tapping Bout Duration During Freely Chosen and Passive Finger Tapping on Rate Enhancement
Published in Journal of Motor Behavior, 2021
Anders Emanuelsen, Michael Voigt, Pascal Madeleine, Ernst Albin Hansen
We have previously investigated the within-bout change (first 30 s compared to last 30 s in 3 min bouts) in freely chosen tapping rate and found it to amount to on average 3%-6% (Hansen et al., 2015). Moreover, we have previously investigated the within-bout change in 3 min tapping bouts (using three 8-s epochs from the start (0-8 s), mid (86-94 s), and end of the bout (172-180 s)). We found that the tapping rate increased from start to mid (on average 4.6%), from start to end (on average 6.7%), and from mid to end (on average 2.2%) (Emanuelsen et al., 2019). To additionally scrutinize the inter-session effects on rate enhancement, an additional analysis on freely chosen tapping rate restricted to the first 20 s of the tapping bouts was performed. Similar results to the analysis of the 180 s tapping bouts were found. These findings suggest that rate enhancement is present early in the 180 s tapping bouts. Moreover, RBRE was documented to occur within sessions for the selected participants who performed active tapping as priming (i.e. A20, A60, A120, and A180). The magnitude of RBRE as a result of active priming ranged from 2.9% to 8.0%. Of note is that these results were calculated for the initial 20 s of the tapping bouts investigated. And this can explain the lower values than the rate enhancement calculated across the entire 180 s of the bouts.
Methylphenidate-mediated motor control network enhancement in patients with traumatic brain injury
Published in Brain Injury, 2018
Charlie L. Dorer, Anne E. Manktelow, Judith Allanson, Barbara J. Sahakian, John D. Pickard, Andrew Bateman, David K. Menon, Emmanuel A. Stamatakis
Evaluation of tapping rate during scanning would allow for a more reliable assessment of motor output and differences that may exist between healthy controls and patients. Unfortunately MRI compatible hardware to collect tapping rate data was not available during this experiment. Data collected in this manner would provide a precise assessment of potential changes which may be due to alteration in the MCN of patients with later-stage TBI.