Publications by authors named "T Uka"
Mismatch negativity (MMN) has gained attention as a biomarker for psychosis and a translational intermediate phenotype in animal models of psychosis, including rodents and non-human primates. MMN has been linked to global functioning (Global Assessment of Functioning [GAF] score) and prognosis (psychosis onset or remission), suggesting that MMN reflects activities beyond auditory processing alone. This review examines the 45-year history of MMN from the perspective of psychiatric researchers and discusses current advances in computational and translational research on MMN, summarizing the current understanding of the MMN generation mechanism.
View Article and Find Full Text PDFHumans can selectively process information and make decisions by directing their attention to desired locations in their daily lives. Numerous studies have shown that attention increases the rate of correct responses and shortens reaction time, and it has been hypothesized that this phenomenon is caused by an increase in sensitivity of the sensory signals to which attention is directed. The present study employed psychophysical methods and electroencephalography (EEG) to test the hypothesis that attention accelerates the onset of information accumulation.
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- Sound frequency and duration play crucial roles in how our brain detects prediction errors, helping us respond swiftly to changing auditory environments.
- An electrocorticography study with 13 participants revealed significant activation in certain brain regions during frequency and duration tasks, highlighting their connection to prediction errors.
- Differences in the brain's response patterns between duration and frequency tasks suggest distinct processing mechanisms, which may help explain certain auditory processing challenges in psychiatric disorders.
Article Synopsis
- Auditory sensory processing occurs in a hierarchical manner involving key brain areas like the primary auditory cortex and the superior temporal gyrus, which help create predictions about sounds.
- A new auditory paradigm called "cascade roving" was developed to study how these brain regions respond to unexpected sounds, analyzing data from epilepsy patients.
- Results showed that while the superior temporal gyrus responded to these unexpected sounds, the inferior frontal gyrus had longer and broader responses, revealing distinct characteristics in auditory processing compared to typical testing methods.
To make flexible decisions in dynamic environments, the brain must integrate behaviorally relevant information while simultaneously discarding irrelevant information. This study aimed to investigate the mechanisms responsible for discarding irrelevant information during context-dependent decision-making. We trained two macaque monkeys to switch between direction and depth discrimination tasks in successive trials.
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