Neuroscience
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Randomized Controlled Trial
Stimulus-driven attention modulates the release of anticipatory postural adjustments during step initiation.
Step initiation can be modified by environmental stimulations, suggesting the involvement of stimulus-driven attention. Therefore, we assessed the influence of attentional status during step preparation. ⋯ The cortical integration of an auditory stimulus (as evidenced by the P300 component) in a subject conditioned to initiate gait appears to release postural adjustments via two different attentional mechanisms: an "alerting effect" and an "orienting effect".
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Randomized Controlled Trial
Correlation between audio-visual enhancement of speech in different noise environments and SNR: a combined behavioral and electrophysiological study.
In the present study, we investigated the multisensory gain as the difference of speech recognition accuracies between the audio-visual (AV) and auditory-only (A) conditions, and the multisensory gain as the difference between the event-related potentials (ERPs) evoked under the AV condition and the sum of the ERPs evoked under the A and visual-only (V) conditions in different noise environments. Videos of a female speaker articulating the Chinese monosyllable words accompanied with different levels of pink noise were used as the stimulus materials. The selected signal-to-noise ratios (SNRs) were -16, -12, -8, -4 and 0 dB. ⋯ The behavioral results showed that the maximum gain as the difference of speech recognition accuracies between the AV and A conditions was at the -12 dB SNR. The ERP results showed that the multisensory gain as the difference between the ERPs evoked under the AV condition and the sum of ERPs evoked under the A and V conditions at the -12 dB SNR was significantly higher than those at the other SNRs in the time window of 130-200 ms in the area from frontal to central region. The multisensory gains in audio-visual speech recognition at different SNRs were not completely accordant with the principle of inverse effectiveness, but confirmed to cross-modal stochastic resonance.
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The article reviews evidence for sensitive periods in the sensory systems and considers their neuronal mechanisms from the viewpoint of the system's neuroscience. It reviews the essential cortical developmental steps and shows its dependence on experience. It differentiates feature representation and object representation and their neuronal mechanisms. ⋯ Additional to developmental molecular effects on synaptic plasticity, a combination of several integrative effects of deprivation on brain functions, including feature representation (affecting the starting point for learning), categorization function, top-down interactions and cross-modal reorganization close the sensitive periods and may contribute to their critical nature. Further, non-auditory effects of auditory deprivation are discussed. To reopen critical periods, removal of molecular breaks in synaptic plasticity and focused training therapy on the integrative effects are required.
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Randomized Controlled Trial
Illumination influences working memory: an EEG study.
Illumination conditions appear to influence working efficacy in everyday life. In the present study, we obtained electroencephalogram (EEG) correlates of working-memory load, and investigated how these waveforms are modulated by illumination conditions. We hypothesized that illumination conditions may affect cognitive performance. ⋯ The fact that the illumination condition affects brain activity but not behavioral performance suggests that the lighting conditions used in the present study did not influence the performance stage of behavioral processing. Nevertheless, our findings provide objective evidence that illumination conditions modulate brain activity. Further studies are necessary to refine the optimal lighting parameters for facilitating working memory.
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Randomized Controlled Trial
Finger-specific loss of independent control of movements in musicians with focal dystonia.
The loss of independent control of finger movements impairs the dexterous use of the hand. Focal hand dystonia is characterised by abnormal structural and functional changes at the cortical and subcortical regions responsible for individuated finger movements and by the loss of surround inhibition in the finger muscles. However, little is known about the pathophysiological impact of focal dystonia on the independent control of finger movements. ⋯ Interestingly, the movement features that contributed to successful classification differed across fingers. Compared to healthy pianists, pianists with an affected index finger were characterised predominantly by stronger keystrokes, whereas pianists with affected middle or ring fingers exhibited abnormal temporal control of the keystrokes, such as slowness and rhythmic inconsistency. The selective alternation of the movement features indicates a finger-specific loss of the independent control of finger movements in focal dystonia of musicians.