The results show that the SMAp stimulation evokes reproducible muscle responses with similar latencies and amplitudes as M1 stimulation, and with a clear and significant shorter silent period. These results suggest that (i) CS projections from human SMAp are

as rapid and efficient as those from M1, (ii) CS projections from SMAp are directly involved in control of the excitability of spinal motoneurons and (iii) SMAp has a different intracortical inhibitory circuitry. selleck chemicals We conclude that human SMAp and M1 both have direct influence on force production during fine manual motor tasks. “
“Brain responses evoked by transcranial magnetic stimulation (TMS) in task-free experimental contexts are known to depend on psychophysiological states such as sleep, vegetative state and caffeine-induced arousal. Much less is known about how TMS-evoked responses depend on task-irrelevant steady perceptual input. Here, we examined ongoing alpha activity and the mean amplitude of EEG potentials in response to occipitally applied TMS as a function of task-irrelevant visual backgrounds. Responses to TMS were robustly

modulated by photographs of natural scenes and man-made environments. These effects began as early as during the N100 and continued for several hundred milliseconds after the stimulation. There was also a more general effect of background along with other stimuli, such as blank backgrounds, sinusoidal gratings and moving Tyrosine Kinase Inhibitor Library in vivo dot-patterns. This effect

was observable from ongoing alpha activity as well. Based on these results we conclude that different types of steady perceptual input modulate visual cortex reactivity and/or connectivity and it is possible to measure these modulations by combining TMS with electroencephalography. “
“Auditory metre perception refers to the ability to extract a temporally regular pulse and an underlying hierarchical structure of perceptual accents from a sequence of tones. Pulse perception is widely present in humans, and can be measured by the temporal expectancy for prospective tones, which listeners generate when presented with a metrical rhythm. We tested whether musical expertise leads to an increased perception and representation of the hierarchical structure of a metrical rhythm. Musicians and musical novices were tested in a mismatch negativity (MMN) paradigm for their sensitivity Carnitine dehydrogenase to perceptual accents on tones of the same pulse level (metre-congruent deviant) and on tones of a lower hierarchical level (metre-incongruent deviant). The difference between these two perceptual accents was more pronounced in the MMNs of the musicians than in those of the non-musicians. That is, musical expertise includes increased sensitivity to metre, specifically to its hierarchical structure. This enhanced higher-order temporal pattern perception makes musicians ideal models for investigating neural correlates of metre perception and, potentially, of related abstract pattern perception.