TY - JOUR
T1 - Cerebellar direct current stimulation modulates hand blink reflex
T2 - implications for defensive behavior in humans
AU - Bocci, Tommaso
AU - Ferrucci, Roberta
AU - Barloscio, Davide
AU - Parenti, Laura
AU - Cortese, Francesca
AU - Priori, Alberto
AU - Sartucci, Ferdinando
PY - 2018/5/1
Y1 - 2018/5/1
N2 - The cerebellum is involved in a wide number of integrative functions. We evaluated the role of cerebellum in peripersonal defensive behavior, as assessed by the so-called hand blink reflex (HBR), modulating cerebellar activity with transcranial direct current stimulation (tDCS). Healthy subjects underwent cerebellar (sham, anodal, and cathodal tcDCS) and motor cortex tDCS (anodal or cathodal; 20′, 2 mA). For the recording of HBR, electrical stimuli were delivered using a surface bipolar electrode placed on the median nerve at the wrist and EMG activity recorded from the orbicularis oculi muscle bilaterally. Depending on the hand position respective to the face, HBR was assessed in four different conditions: “hand-far,” “hand-near” (eyes open), “side hand,” and “hand-patched” (eyes closed). While sham and cathodal cerebellar stimulation had no significant effect, anodal tcDCS dramatically dampened the magnitude of the HBR, as measured by the area under the curve (AUC), in the “hand-patched” and “side hand” conditions only, for ipsilateral (F(4,171) = 15.08, P < 0.0001; F(4,171) = 8.95, P < 0.0001) as well as contralateral recordings (F(4,171) = 17.96, P < 0.0001); F4,171) = 5.35, P = 0.0004). Cerebellar polarization did not modify AUC in the “hand-far” and “hand-near” sessions. tDCS applied over the motor area did not affect HBR. These results seem to support a role of the cerebellum in the defensive responses within the peripersonal space surrounding the face, thus suggesting a possible cerebellar involvement in visual-independent defensive behavior.
AB - The cerebellum is involved in a wide number of integrative functions. We evaluated the role of cerebellum in peripersonal defensive behavior, as assessed by the so-called hand blink reflex (HBR), modulating cerebellar activity with transcranial direct current stimulation (tDCS). Healthy subjects underwent cerebellar (sham, anodal, and cathodal tcDCS) and motor cortex tDCS (anodal or cathodal; 20′, 2 mA). For the recording of HBR, electrical stimuli were delivered using a surface bipolar electrode placed on the median nerve at the wrist and EMG activity recorded from the orbicularis oculi muscle bilaterally. Depending on the hand position respective to the face, HBR was assessed in four different conditions: “hand-far,” “hand-near” (eyes open), “side hand,” and “hand-patched” (eyes closed). While sham and cathodal cerebellar stimulation had no significant effect, anodal tcDCS dramatically dampened the magnitude of the HBR, as measured by the area under the curve (AUC), in the “hand-patched” and “side hand” conditions only, for ipsilateral (F(4,171) = 15.08, P < 0.0001; F(4,171) = 8.95, P < 0.0001) as well as contralateral recordings (F(4,171) = 17.96, P < 0.0001); F4,171) = 5.35, P = 0.0004). Cerebellar polarization did not modify AUC in the “hand-far” and “hand-near” sessions. tDCS applied over the motor area did not affect HBR. These results seem to support a role of the cerebellum in the defensive responses within the peripersonal space surrounding the face, thus suggesting a possible cerebellar involvement in visual-independent defensive behavior.
KW - Cerebellar direct current stimulation
KW - cerebellum
KW - defensive behavior
KW - hand blink reflex
KW - peripersonal space
KW - tDCS
UR - http://www.scopus.com/inward/record.url?scp=85047567182&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85047567182&partnerID=8YFLogxK
U2 - 10.14814/phy2.13471
DO - 10.14814/phy2.13471
M3 - Article
AN - SCOPUS:85047567182
VL - 6
JO - Physiological Reports
JF - Physiological Reports
SN - 2051-817X
IS - 10
M1 - e13471
ER -