Interneuronal networks mediate cortical inhibition and facilitation.
Clin Neurophysiol
; 131(5): 1000-1010, 2020 05.
Article
en En
| MEDLINE
| ID: mdl-32193161
ABSTRACT
OBJECTIVE:
Recruitment of interneuronal circuits generating later indirect (I) waves seem to be important in short-interval intracortical inhibition (SICI) and facilitation (SICF) development. This study assessed whether individual variations in intracortical inhibition and facilitation could be explained by variation in recruitment of interneuronal networks.METHODS:
Cortical excitability was assessed using a figure of eight coil, with motor evoked responses recorded over the contralateral abductor pollicis brevis (APB) muscle. I-wave recruitment was inferred from the measurement of motor evoked potential (MEP) onset latencies, with coil positioned in posterior-to-anterior (early I waves) and anterior-to-posterior (later I waves) directions.RESULTS:
Subtle variability in the recruitment of later I-waves (I3) was evident across subjects. Importantly, mean SICI (P < 0.05) was significantly greater in subjects recruiting I3 waves, as were the two SICI peaks at interstimulus intervals of 1 ms (P < 0.05) and 3 ms (P < 0.05). In addition, mean SICF was significantly greater in participants exhibiting an AP-to-LM latency differences of <4 ms (P < 0.01). There was no significant correlation between I-wave recruitment and intracortical facilitation, motor evoked potential amplitude or cortical silent period duration.CONCLUSIONS:
Differential recruitment of interneuronal networks appears to underlie the generation and individual variations in intracortical inhibition and facilitation.SIGNIFICANCE:
Investigating cortical interneuronal networks in human diseases may yield novel pathophysiological insights.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Potenciales Evocados Motores
/
Interneuronas
/
Corteza Motora
/
Red Nerviosa
/
Inhibición Neural
Límite:
Adult
/
Aged
/
Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Clin Neurophysiol
Asunto de la revista:
NEUROLOGIA
/
PSICOFISIOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Australia