Meral E Kiziltan1, Aysegul Gunduz2, Hulya Apaydın1, Sibel Ertan1, Gunes Kiziltan1. 1. Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey. 2. Department of Neurology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey. Electronic address: draysegulgunduz@yahoo.com.
Abstract
OBJECTIVE: Startle reflex is a generalized defense reaction after unexpected auditory, visual, or tactile stimuli. Auditory startle reflex (ASR) and startle reflex to somatosensory inputs (SSS) have never been studied in generalized dystonia. Here, we aimed to study the characteristics and changes of ASR and SSS in this group. METHODS: We have examined ASR and SSS in patients with generalized dystonia (n=11) and healthy subjects (n=25) under the same conditions. ASRs and SSSs were recorded over the orbicularis oculi (O.oc), sternocleidomastoid, biceps brachii (BB), and abductor pollicis brevis (APB) muscles after bilateral auditory stimulation and unilateral median nerve electrical stimulation at the wrist, respectively. RESULTS: Both ASR and SSS showed the same sequence of muscle activation in both groups. However, the presence rates over the APB and BB muscles after both modalities of stimuli were significantly higher in the generalized dystonia group. ASR did not habituate in the dystonia group. CONCLUSIONS: Both ASR and SSS are disinhibited, and both show a similar sequence of muscle recruitment in generalized dystonia. SIGNIFICANCE: Higher probabilities over caudal muscles probably depend on the higher excitability of motor neurons secondary to central modulation.
OBJECTIVE:Startle reflex is a generalized defense reaction after unexpected auditory, visual, or tactile stimuli. Auditory startle reflex (ASR) and startle reflex to somatosensory inputs (SSS) have never been studied in generalized dystonia. Here, we aimed to study the characteristics and changes of ASR and SSS in this group. METHODS: We have examined ASR and SSS in patients with generalized dystonia (n=11) and healthy subjects (n=25) under the same conditions. ASRs and SSSs were recorded over the orbicularis oculi (O.oc), sternocleidomastoid, biceps brachii (BB), and abductor pollicis brevis (APB) muscles after bilateral auditory stimulation and unilateral median nerve electrical stimulation at the wrist, respectively. RESULTS: Both ASR and SSS showed the same sequence of muscle activation in both groups. However, the presence rates over the APB and BB muscles after both modalities of stimuli were significantly higher in the generalized dystonia group. ASR did not habituate in the dystonia group. CONCLUSIONS: Both ASR and SSS are disinhibited, and both show a similar sequence of muscle recruitment in generalized dystonia. SIGNIFICANCE: Higher probabilities over caudal muscles probably depend on the higher excitability of motor neurons secondary to central modulation.
Authors: Jacek Polechoński; Grzegorz Juras; Kajetan Słomka; Janusz Błaszczyk; Andrzej Małecki; Agnieszka Nawrocka Journal: Biomed Res Int Date: 2016-05-22 Impact factor: 3.411