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Kuc, A.

Publications and source records attributed to Kuc, A..

3 recordsLinked to original sources

Transcranial Magnetic Stimulation Reduces Non-Decision Time in Perceptual Decisions

Perceptual decision-making enables humans to process sensory information and translate it into goal-directed actions. A critical component of this process is response time, which declines with age due to the slowing of both non-decision processes and evidence accumulation. While perceptual learning has been shown to counteract these declines, it remains unclear whether non-decision processes can be accelerated through direct neural stimulation, bypassing the need for long training sessions. Here, we propose that Transcranial Magnetic Stimulation (TMS) can enhance perceptual decision-making by specifically reducing non-decision time. To test this hypothesis, we tracked response times during a perceptual learning task while recording brain activity. Using the Drift Diffusion Model, we quantified the effects of TMS on mental speed and non-decision time. Our findings reveal that perceptual learning decreases response time by simultaneously increasing mental speed and reducing non-decision time. Crucially, TMS application to brain regions associated with perceptual learning further shortened non-decision time without altering mental speed. These results demonstrate that TMS can selectively accelerate non-decision processes, offering a promising intervention for mitigating age-related cognitive slowing and enhancing decision efficiency. Significance StatementPerceptual decision-making is a fundamental cognitive process that slows with age due to declines in both non-decision processes and mental speed. While perceptual learning can mitigate these declines through practice, we propose that non-decision time can also be reduced by directly stimulating neural ensembles using Transcranial Magnetic Stimulation (TMS). Our study demonstrates that TMS applied to task-relevant brain areas decreases non-decision time, thereby accelerating response speed without affecting mental speed. These findings reveal a novel mechanism for enhancing perceptual decision-making efficiency and highlight TMS as a potential tool for counteracting age-related cognitive slowing.

neuroscience↗

High-level stimulus template modulates neuronal response at the earlier processing stages

There is ample evidence that the brain matches sensory information with internal templates, but the details of this mechanism remain unknown. Here we consider the processing of repeatedly presented ambiguous stimuli with high ambiguity (HA) and low ambiguity (LA) and analyze how the processing depends on the ambiguity of the previous stimulus. On the behavioral level, we report a faster response to the HA stimulus after HA stimuli and a faster response to the LA stimulus after LA stimuli. The EEG analysis reveals that when HA stimulus follows LA stimuli, the neuronal activity in the sensory areas attenuates at the early processing stage but enhances during the latter stages. It evidences the hierarchical processing organization where low levels process the stimulus details, and high levels represent its interpretation. It also confirms that on low levels, HA and LA stimuli processing is similar due to their similar morphology. Therefore, the brain uses the LA stimulus template on the low levels to reduce the demands when processing the HA stimulus details. When LA stimulus follows HA stimuli, the attenuated response in the sensory regions accompanies high response in the frontal cortex. Namely, we observe high{theta} power in the medial frontal cortex and high {beta} power in the right inferior frontal cortex. It shows activation of the top-down cognitive control functions detecting the mismatch between the LA stimulus and the HA stimulus template and transfer this template to the low processing levels. Significance statementThe brain attenuates its response to repeatedly presented similar stimuli. When an ambiguous visual stimulus follows unambiguous stimuli with the same morphology, the neuronal response in sensory areas decreases at the early processing stage but enhances during the latter stages. It evidences hierarchical processing organization where low levels process the details, and high levels represent the interpretation. It also confirms that the brain uses templates on different levels to reduce the processing demands. When an unambiguous stimulus follows ambiguous stimuli, a low response in the sensory regions accompanies high response in the frontal cortex. It manifests activation of the top-down mechanisms to detect the mismatch between an unambiguous stimulus and an ambiguous template and transfer this template to low levels.

neuroscience↗

Neuronal adaptation during the prolonged cognitive task improves visual stimulus processing

Brain optimally utilizes resources to resist mental fatigue during the prolonged period of cognitive activity. Neural mechanisms underlying long-term cognitive performance remain unknown. We show that during the 40-minutes visual stimuli classification task, subjects improve behavioral performance in terms of response time and correctness. We observe that the prestimulus{theta} and power grows during the experiment manifesting the mental fatigue. The prestimulus {beta} power, in its turn, increases locally in the region, engaged in the ongoing stimulus processing, that may reflect the neuronal adaptation. Our results evidence that the neuronal adaptation is enhanced in the course of the experiment reducing the cognitive demands required to activate the stimulus-related brain regions.

neuroscience↗