This suggests little effect on the feedforward settings of the nervous system responsible for coupling pure vestibular input to functional motor output. The much stronger,
later effect can be attributed to an integration of balance-relevant sensory feedback once the body was in motion. These results demonstrate that the feedforward and feedback components of a vestibular-evoked balance response are differently affected by Bleomycin mouse postural threat. Although a fear of falling has previously been linked with instability and even falling itself, our findings suggest that this relationship is not attributable to changes in the feedforward vestibular control of balance. “
“The role of induced gamma-band responses (iGBRs) in the human electroencephalogram
(EEG) is a controversial topic. On selleck chemical the one hand, iGBRs have been associated with neuronal activity reflecting the (re-)activation of cortical object representations. On the other hand, it was shown that miniature saccades (MSs) lead to high-frequency artifacts in the EEG that can mimic cortical iGBRs. We recorded EEG and eye movements simultaneously while participants were engaged in a combined repetition priming and object recognition experiment. MS rates were mainly modulated by object familiarity in a time window from 100 to 300 ms after stimulus onset. In contrast, artifact-corrected iGBRs were sensitive to object repetition and object familiarity in a prolonged time window. EEG source analyses revealed that stimulus repetitions modulated iGBRs in temporal and occipital cortex regions while familiarity was associated with activity in parieto-occipital regions. These results are in line with neuroimaging studies employing functional
magnetic resonance imaging Pazopanib in vivo or magnetoencephalography. We conclude that MSs reflect early mechanisms of visual perception while iGBRs mirror the activation of cortical networks representing a perceived object. “
“Visuomotor adaptation is often driven by error-based (EB) learning in which signed errors update motor commands. There are, however, visuomotor tasks where signed errors are unavailable or cannot be mapped onto appropriate motor command changes, rendering EB learning ineffective; and yet, healthy subjects can learn in these EB learning-free conditions. While EB learning depends on cerebellar integrity, the neural bases of EB-independent learning are poorly understood. As basal ganglia are involved in learning mechanisms that are independent of signed error feedback, here we tested whether patients with basal ganglia lesions, including those with Huntington’s disease and Parkinson’s disease, would show impairments in a visuomotor learning task that prevents the use of EB learning. We employed two visuomotor throwing tasks that were similar, but were profoundly different in the resulting visual feedback.