International journal of psychophysiology : official journal of the International Organization of Psychophysiology
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Recollection of events from one's own life is referred to as autobiographical memory. Autobiographical memory is an important part of our self. Neuroimaging findings link self-referential processes with the default mode network (DMN). ⋯ In line with data linking delta oscillations with aversive states, decrease of delta power was more pronounced in episodes associated with positive emotions, whereas episodes associated with negative emotions were accompanied by an increase of delta power. Vividness of recollection correlated positively with theta oscillations. These results highlight the leading role of alpha oscillations and the DMN in the processes accompanying autobiographical remembering.
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Int J Psychophysiol · Oct 2014
Frontal EEG delta/alpha ratio and screening for post-stroke cognitive deficits: the power of four electrodes.
This study analysed correlations between post-stroke, quantitative electroencephalographic (QEEG) indices, and cognition-specific, functional outcome measures. Results were compared between QEEG indices calculated from the standard 19 versus 4 frontal (or 4 posterior) electrodes to assess the feasibility and efficacy of employing a reduced electrode montage. Resting-state EEG was recorded at the bedside within 62-101 h after onset of symptoms of middle cerebral artery, ischaemic stroke (confirmed radiologically). ⋯ Alpha activity - particularly frontally - may index post-stroke attentional capacity, which appears to be a key determinant of functional and cognitive outcomes. Likewise frontal delta pathophysiology influences such outcomes. Pending further studies, DAR from 4 frontal electrodes may inform early screening for post-MCA stroke cognitive deficits, and thereby, clinical decisions.
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Int J Psychophysiol · Sep 2014
Age-related spatiotemporal reorganization during response inhibition.
As a key high-level cognitive function in human beings, response inhibition is crucial for adaptive behavior. Previous neuroimaging studies have shown that older individuals exhibit greater neural activation than younger individuals during response inhibition tasks. This finding has been interpreted within a neural compensation framework, in which additional neural resources are recruited in response to age-related cognitive decline. ⋯ Further, such age-related differences in neural activation were successfully separated between the N2 and P3 periods by source localization analysis. Interestingly, the increased activations in older adults were primarily localized to the right precentral and postcentral gyri during the N2 period, which shifted to the right dorsolateral prefrontal cortex and the right inferior frontal gyrus during the P3 period. Taken together, our results clearly illustrate the spatiotemporal dynamics of age-related functional brain reorganization, and further specify the exact temporal course at the millisecond scale by which age-related compensatory neural responses occur during response inhibition.
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Int J Psychophysiol · Aug 2014
Different strategies in solving series completion inductive reasoning problems: an fMRI and computational study.
Neural correlate of human inductive reasoning process is still unclear. Number series and letter series completion are two typical inductive reasoning tasks, and with a common core component of rule induction. Previous studies have demonstrated that different strategies are adopted in number series and letter series completion tasks; even the underlying rules are identical. ⋯ The procedural strategy produced significant greater activity in areas involved in memory retrieval (dorsolateral prefrontal cortex, DLPFC) and mental representation/maintenance (posterior parietal cortex, PPC). An ACT-R model of the tasks successfully predicted behavioral performance and BOLD responses. The present findings support a general-purpose dual-process theory of inductive reasoning regarding the cognitive architecture.
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Studies on the potential benefits of conveying biofeedback stimulus using a musical signal have appeared in recent years with the intent of harnessing the strong effects that music listening may have on subjects. While results are encouraging, the fundamental question has yet to be addressed, of how combined music and biofeedback compares to the already established use of either of these elements separately. This experiment, involving young adults (N = 24), compared the effectiveness at modulating participants' states of physiological arousal of each of the following conditions: A) listening to pre-recorded music, B) sonification biofeedback of the heart rate, and C) an algorithmically modulated musical feedback signal conveying the subject's heart rate. ⋯ Several physiological measures and qualitative responses were recorded and analyzed. Results show that using musical biofeedback allowed participants to modulate their state of physiological arousal at least equally well as sonification biofeedback, and much better than just listening to music, as reflected in their heart rate measurements, controlling for respiration-rate. Our findings indicate that the known effects of music in modulating arousal can therefore be beneficially harnessed when designing a biofeedback protocol.