Auditory cortex hyperconnectivity before rTMS is correlated with tinnitus improvement.

INTRODUCTION: Repetitive transcranial magnetic stimulation (rTMS) has been used as a potential treatment for tinnitus; however, its effectiveness is variable and unpredictable. We hypothesized that resting-state functional connectivity before rTMS may be correlated with rTMS treatment effectiveness. METHODS: We applied 1-Hz rTMS to the left primary auditory (A1) and dorsolateral prefrontal cortices (DLPFC) of 10 individuals with tinnitus and 10 age-matched controls. Resting-state functional magnetic resonance imaging (fMRI) studies were performed approximately one week before rTMS. Seed-based connectivity analyses were conducted for each individual, with seed regions as rTMS target areas. RESULTS: Compared to controls, the left superior temporal areas showed significantly increased positive connectivity with the left A1 and negative connectivity with the left DLPFC in the tinnitus group. The left frontoparietal and right cerebellar areas showed significantly increased negative connectivity with the left A1 and positive connectivity with the left DLPFC. Seed-based hyperconnectivity was correlated with tinnitus improvement (pre-rTMS vs. 2-week post-rTMS Tinnitus Handicap Inventory scores). Tinnitus improvement was significantly correlated with left A1 hyperconnectivity; however, no correlation was observed with left DLPFC connectivity. Positive rTMS outcomes were associated with significantly increased positive connectivity in bilateral superior temporal areas and significantly increased negative connectivity in bilateral frontal areas. CONCLUSIONS: Our results suggest that oversynchronisation of left A1 connectivity before rTMS of the left A1 and DLPFC is associated with treatment effectiveness.

Auditory cortex hyperconnectivity before rTMS is correlated with tinnitus improvement / Correlación entre hiperconectividad de la corteza auditiva antes del tratamiento con estimulación magnética transcraneal repetitiva y mejoría de los acúfenos

Introduction: Repetitive transcranial magnetic stimulation (rTMS) has been used as a potential treatment for tinnitus; however, its effectiveness is variable and unpredictable. We hypothesized that resting-state functional connectivity before rTMS may be correlated with rTMS treatment effectiveness. Methods: We applied 1-Hz rTMS to the left primary auditory (A1) and dorsolateral prefrontal cortices (DLPFC) of 10 individuals with tinnitus and 10 age-matched controls. Resting-state functional magnetic resonance imaging (fMRI) studies were performed approximately one week before rTMS. Seed-based connectivity analyses were conducted for each individual, with seed regions as rTMS target areas. Results: Compared to controls, the left superior temporal areas showed significantly increased positive connectivity with the left A1 and negative connectivity with the left DLPFC in the tinnitus group. The left frontoparietal and right cerebellar areas showed significantly increased negative connectivity with the left A1 and positive connectivity with the left DLPFC. Seed-based hyperconnectivity was correlated with tinnitus improvement (pre-rTMS vs. 2-week post-rTMS Tinnitus Handicap Inventory scores). Tinnitus improvement was significantly correlated with left A1 hyperconnectivity; however, no correlation was observed with left DLPFC connectivity. Positive rTMS outcomes were associated with significantly increased positive connectivity in bilateral superior temporal areas and significantly increased negative connectivity in bilateral frontal areas. Conclusions: Our results suggest that oversynchronisation of left A1 connectivity before rTMS of the left A1 and DLPFC is associated with treatment effectiveness.(AU)

Introducción: La estimulación magnética transcraneal repetitiva (EMTr) se ha utilizado como posible tratamiento para los acúfenos, aunque su efectividad es variable e impredecible. Planteamos la hipótesis de que existe una correlación entre la conectividad funcional en estado de reposo antes de aplicar EMTr y la efectividad de dicho tratamiento. Métodos: Aplicamos EMTr a 1 Hz sobre la corteza auditiva primaria (A1) y la corteza prefrontal dorsolateral (CPFDL) izquierdas de 10 pacientes con acúfenos y 10 controles del mismo rango de edad. Se realizaron estudios de resonancia magnética funcional (RMF) en estado de reposo de todos los pacientes aproximadamente una semana antes de la EMTr. En cada caso, se construyó un mapa de conectividad basado en las ROIs, en el que las ROIs eran las áreas que se tratarían con la EMTr. Resultados: La región temporal superior izquierda mostró una conectividad positiva significativamente mayor con el área A1 izquierda y mayor conectividad negativa con la CPFDL izquierda en los pacientes con acúfenos que en los controles. Además, las áreas frontoparietal izquierda y cerebelar derecha mostraron una conectividad negativa significativamente superior con el área A1 izquierda y mayor conectividad positiva con la CPFDL izquierda. La hiperconectividad de las ROIs se correlacionó con mejoría de los acúfenos según las puntuaciones pre-EMTr y 2 semanas post-EMTr en la escala Tinnitus Handicap Inventory. La mejoría de los acúfenos se correlacionó de manera significativa con la hiperconectividad del área A1 izquierda; sin embargo, no se encontró correlación con la conectividad de la CPFDL izquierda. El resultado favorable del tratamiento con EMTr se asocia con una mayor conectividad positiva en áreas temporales superiores de ambos hemisferios y con mayor conectividad negativa en áreas frontales bilaterales...(AU)

Auditory cortex hyperconnectivity before rTMS is correlated with tinnitus improvement.

INTRODUCTION: Repetitive transcranial magnetic stimulation (rTMS) has been used as a potential treatment for tinnitus; however, its effectiveness is variable and unpredictable. We hypothesized that resting-state functional connectivity before rTMS may be correlated with rTMS treatment effectiveness. METHODS: We applied 1-Hz rTMS to the left primary auditory (A1) and dorsolateral prefrontal cortices (DLPFC) of 10 individuals with tinnitus and 10 age-matched controls. Resting-state functional magnetic resonance imaging (fMRI) studies were performed approximately one week before rTMS. Seed-based connectivity analyses were conducted for each individual, with seed regions as rTMS target areas. RESULTS: Compared to controls, the left superior temporal areas showed significantly increased positive connectivity with the left A1 and negative connectivity with the left DLPFC in the tinnitus group. The left frontoparietal and right cerebellar areas showed significantly increased negative connectivity with the left A1 and positive connectivity with the left DLPFC. Seed-based hyperconnectivity was correlated with tinnitus improvement (pre-rTMS vs. 2-week post-rTMS Tinnitus Handicap Inventory scores). Tinnitus improvement was significantly correlated with left A1 hyperconnectivity; however, no correlation was observed with left DLPFC connectivity. Positive rTMS outcomes were associated with significantly increased positive connectivity in bilateral superior temporal areas and significantly increased negative connectivity in bilateral frontal areas. CONCLUSIONS: Our results suggest that oversynchronisation of left A1 connectivity before rTMS of the left A1 and DLPFC is associated with treatment effectiveness.