Differential Effects of Startle on Reaction Time for Finger and Arm Movements
- 1 January 2009
- journal article
- research article
- Published by American Physiological Society in Journal of Neurophysiology
- Vol. 101 (1), 306-314
- https://doi.org/10.1152/jn.00878.2007
Abstract
Recent studies using a reaction time (RT) task have reported that a preprogrammed response could be triggered directly by a startling acoustic stimulus (115–124 dB) presented along with the usual “go” signal. It has been suggested that details of the upcoming response could be stored subcortically and are accessible by the startle volley, directly eliciting the correct movement. However, certain muscles (e.g., intrinsic hand) are heavily dependent on cortico-motoneuronal connections and thus would not be directly subject to the subcortical startle volley in a similar way to muscles whose innervations include extensive reticular connections. In this study, 14 participants performed 75 trials in each of two tasks within a RT paradigm: an arm extension task and an index finger abduction task. In 12 trials within each task, the regular go stimulus (82 dB) was replaced with a 115-dB startling stimulus. Results showed that, in the arm task, the presence of a startle reaction led to significantly shorter latency arm movements compared with the effect of the increased stimulus intensity alone. In contrast, for the finger task, no additional decrease in RT caused by startle was observed. Taken together, these results suggest that only movements that involve muscles more strongly innervated by subcortical pathways are susceptible to response advancement by startle.Keywords
This publication has 47 references indexed in Scilit:
- Choice reaction times for human head rotations are shortened by startling acoustic stimuli, irrespective of stimulus directionThe Journal of Physiology, 2007
- Fast visuomotor processing made faster by soundThe Journal of Physiology, 2007
- The neural correlates of habituation of response to startling tactile stimuli presented in a functional magnetic resonance imaging environmentPsychiatry Research: Neuroimaging, 2006
- Descending Signals From the Pontomedullary Reticular Formation Are Bilateral, Asymmetric, and Gated During Reaching Movements in the CatJournal of Neurophysiology, 2006
- Excitability of subcortical motor circuits in Go/noGo and forced choice reaction time tasksNeuroscience Letters, 2006
- Altered Triggering of a Prepared Movement by a Startling StimulusJournal of Neurophysiology, 2003
- Role of brainstem-spinal projections in voluntary movementMovement Disorders, 2002
- Startle response of human neck muscles sculpted by readiness to perform ballistic head movementsThe Journal of Physiology, 2001
- Effects of the intensity of auditory and visual ready signals on simple reaction time.Journal of Experimental Psychology, 1969
- Hand function in hemiplegiaJournal of Chronic Diseases, 1965