Body Sway Increases After Functional Inactivation of the Cerebellar Vermis by cTBS

Abstract

Balance stability correlates with cerebellar vermis volume. Furthermore, the cerebellum is involved in precise timing of motor processes by fine-tuning the sensorimotor integration. We tested the hypothesis that any cerebellar action in stance control and in timing of visuomotor integration for balance is impaired by continuous theta-burst stimulation (cTBS) of the vermis. Ten subjects stood quietly and underwent six sequences of 10-min acquisition of center of foot pressure (CoP) data after cTBS, sham stimulation, and no stimulation. Visual shifts from eyes closed (EC) to eyes open (EO) and vice versa were presented via electronic goggles. Mean anteroposterior and mediolateral CoP position and oscillation, and the time delay at which body sway changed after visual shift were calculated. CoP position under both EC and EO condition was not modified after cTBS. Sway path length was greater with EC than EO and increased in both visual conditions after cTBS. CoP oscillation was also larger with EC and increased under both visual conditions after cTBS. The delay at which body oscillation changed after visual shift was longer after EC to EO than EO to EC, but unaffected by cTBS. The time constant of decrease or increase of oscillation was longer in EC to EO shifts, but unaffected by cTBS. Functional inactivation of the cerebellar vermis is associated with increased sway. Despite this, cTBS does not detectably modify onset and time course of the sensorimotor integration process of adaptation to visual shifts. Cerebellar vermis normally controls oscillation, but not timing of adaptation to abrupt changes in stabilizing information.

The cerebellum after trauma: Resting‐state functional connectivity of the cerebellum in posttraumatic stress disorder and its dissociative subtype

“…The anterior vermis also contains a complete somatosensory map of the body (Kandel, Schwartz, Jessell, Siegelbaum, & Hudspeth, ). Furthermore, it plays a key role in maintaining balance through somatosensory integration of visual and proprioceptive inputs and facilitates execution of body movements (Colnaghi, Honeine, Sozzi, & Schieppati, ) using sensory feedback to control muscle tone and movements (Kandel et al, ). At the same time, the vermis is considered part of the limbic cerebellum, crucial for motivation and emotion processing (O'Halloran, Kinsella, & Storey, ; Schmahmann, ; Schutter & van Honk, ).…”

“…The anterior vermis also contains a complete somatosensory map of the body (Kandel, Schwartz, Jessell, Siegelbaum, & Hudspeth, 2012). Furthermore, it plays a key role in maintaining balance through somatosensory integration of visual and proprioceptive inputs and facilitates execution of body movements (Colnaghi, Honeine, Sozzi, & Schieppati, 2017) using sensory feedback to control muscle tone and movements (Kandel et al, 2012 2005). Depression and anxiety disorders have been linked to abnormalities in the anterior vermis structure and functionality (Schutter, 2013 Moreover, increased levels of state anxiety correlated positively with increased functional connectivity of the anterior vermis with the fusiform gyrus.…”

Gap junction plasticity as a mechanism to regulate network-wide oscillations

“…Firstly, FS interneurons selectively amplify gamma frequencies through subthreshold resonance [ 33 ]. Secondly, gap junctions between inhibitory interneurons [ 27 ] have been shown to enhance synchrony [ 24 , 26 , 35 – 41 ].…”

Chloride Homeostasis in Neurons With Special Emphasis on the Olivocerebellar System: Differential Roles for Transporters and Channels

“…Zhang et al ( 2017 ) investigated the behavioral consequences of Ano2 absence and found that Ano2 knockout mice had significant deficits in their motor learning performance during classical eyeblink conditioning, a cerebellar dependent task where a conditioned stimulus (light/sound) predicts the arrival of an unconditioned stimulus (air puff). However, the idea that a cerebellar related dysfunction in behavior can solely be due to IO expression of Ano2 has recently been put to question (Neureither et al, 2017 ). In this study, Neureither et al ( 2017 ) proposed the previously mentioned depolarization-induced depression of inhibition in PCs to be the main cause for the motor deficits found in their Ano2 knockout model.…”

“…However, the idea that a cerebellar related dysfunction in behavior can solely be due to IO expression of Ano2 has recently been put to question (Neureither et al, 2017 ). In this study, Neureither et al ( 2017 ) proposed the previously mentioned depolarization-induced depression of inhibition in PCs to be the main cause for the motor deficits found in their Ano2 knockout model. In this respect, it is important to emphasize that even though the Ano2 protein is abundantly expressed in the IO, there is also evidence for its expression in other brain areas involved in motor function, including the thalamus (Table 2 ).…”