The early release of actions by loud sounds in muscles with distinct connectivity

• Published in: Experimental brain research 2014-12, Vol.232 (12), p.3797-3802
• Main Authors: Marinovic, Welber, de Rugy, Aymar, Riek, Stephan, Tresilian, James R.
• Format: Article
• Language: English
• Subjects: Acoustic Stimulation; Adult; Auditory perception; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Brain research; Electromyography; Feedback; Female; Fundamental and applied biological sciences. Psychology; Human mechanics; Humans; Male; Motion perception (Vision); Movement - physiology; Muscle Contraction - physiology; Muscle, Skeletal - physiology; Neurology; Neurosciences; Physiological aspects; Psychomotor Performance - physiology; Reaction Time - physiology; Reflex, Startle - physiology; Research Article; Sound; Vertebrates: nervous system and sense organs
• ISSN: 0014-4819; 1432-1106
• DOI: 10.1007/s00221-014-4074-y

The presentation of an unexpected and loud auditory stimulus (LAS) during action preparation can trigger movement onset much sooner than normal. Recent research has attributed this effect to the activation of reticulospinal connections to the target muscles. To our knowledge, no studies have investigated the effects of LAS presentation in tasks requiring the simultaneous activation of muscles with different connectivity to motor areas of the brain. Here, we sought to establish the importance of muscle connectivity by asking participants to contract the orbicularis oris and abductor pollicis brevis muscles simultaneously. A LAS was randomly presented at 200 ms prior to the expected time of movement onset in an anticipatory timing task. We show that muscles controlled via bulbar connections to reticular formation can be triggered early by sound as much as muscles with spinal connections to the reticular formation.