We have investigated the impact of stochastic transmission on the input-output relations of neurons in hippocampal slices. A synaptic input that fires a cell has a significant trial-to-trial variability in amplitude, reflecting the probabilistic release of transmitter. By measuring miniature excitatory postsynaptic currents, we estimate that synchronous release of a few vesicles can fire a CA1 cell. The firing threshold and variability can be physiologically modulated. Different cell types have distinct firing thresholds and variabilities. Long-term potentiation (LTP) decreases trial-to-trial variability. If after LTP, the stimulus is reduced to produce a threshold response, the variability returns to that observed before LTP. Thus, for a threshold input, the trial-to-trial variability is maintained with LTP. This may be important for the proper functioning of a plastic nervous system.
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http://dx.doi.org/10.1016/0896-6273(93)90058-y | DOI Listing |
Neural Comput
January 2025
Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, 200437, China
Spiking neural networks (SNNs) have attracted significant interest in the development of brain-inspired computing systems due to their energy efficiency and similarities to biological information processing. In contrast to continuous-valued artificial neural networks, which produce results in a single step, SNNs require multiple steps during inference to achieve a desired accuracy level, resulting in a burden in real-time response and energy efficiency. Inspired by the tradeoff between speed and accuracy in human and animal decision-making processes, which exhibit correlations among reaction times, task complexity, and decision confidence, an inquiry emerges regarding how an SNN model can benefit by implementing these attributes.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, USA.
The vestibular system is vital for maintaining stable vision during daily activities. When peripheral vestibular input is lost, patients initially experience impaired gaze stability due to reduced effectiveness of the vestibular-ocular-reflex pathway. To aid rehabilitation, patients are often prescribed gaze-stabilization exercises during which they make self-initiated active head movements.
View Article and Find Full Text PDFCogn Neurodyn
December 2024
Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China.
Unlabelled: Data-driven strategies have been widely used to distinguish experimental effects on single-trial EEG signals. However, how latency variability, such as within-condition jitter or latency shifts between conditions, affects the performance of EEG classifiers has not been well investigated. Without explicitly considering and disentangling such attributes of single trials, neural network-based classifiers have limitations in measuring their contributions.
View Article and Find Full Text PDFHum Mov Sci
December 2024
Program in Physical Therapy, Washington University School of Medicine, CB 8502, 4444 Forest Park Ave., Suite 1101, St. Louis, MO 63108-2212, United States; Program in Occupational Therapy, Washington University School of Medicine, MSC 8505-66-1, 4444 Forest Park Avenue, St. Louis, MO 63108-2212, United States; Department of Neurology, Washington University School of Medicine, MSC 8111-29-9000, 660 S. Euclid Ave., St. Louis, MO 63110, United States. Electronic address:
Introduction: During practice, learners use available feedback from one trial to develop and implement motor commands for the next trial. Unsuccessful trials (i.e.
View Article and Find Full Text PDFExp Brain Res
December 2024
Department of Biomedical Engineering, 9500 Euclid Avenue, ND-20, Cleveland, OH, 44195, USA.
The controlled release of grasping forces underlies skilled dexterous interactions with objects. While declines in force generation and maintenance are well documented in people with Parkinson's disease (PwPD), limited data exist related to how PD impacts the motor control of grasping force release. The aim of this project was to determine how PD impacts grip force release relative to the generation and maintenance of force.
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