Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1212/wnl.41.6.869 | DOI Listing |
Acetylcholine modulates the network physiology of the hippocampus, a crucial brain structure that supports cognition and memory formation in mammals . In this and adjacent regions, synchronized neuronal activity within theta-band oscillations (4-10Hz) is correlated with attentive processing that leads to successful memory encoding . Acetylcholine facilitates the hippocampus entering a theta oscillatory regime and modulates the temporal organization of activity within theta oscillations .
View Article and Find Full Text PDFPLoS Biol
January 2025
Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America.
Worrying about perceived threats is a hallmark of multiple psychological disorders including anxiety. This concern about future events is particularly important when an individual is faced with an approach-avoidance conflict. Potential goals to approach are known to be represented in the dorsal hippocampus during theta cycles.
View Article and Find Full Text PDFBehav Brain Res
January 2025
Department of Neurology, Changzhi People's Hospital, Changzhi, Shanxi Province 046000, China. Electronic address:
Memory is the ability to acquire and store information following an experience, which can be retrieved by related context exposure. Pioneering studies have demonstrated that sparsely distributed neuronal ensembles or engram cells can serve as neural substrates for storing and recalling memory traces. Many studies of neuronal ensembles have focused on the hippocampus, and increasing evidence has indicated that the neuronal oscillation is closely associated with hippocampal memory functions, including both encoding and retrieval processes.
View Article and Find Full Text PDFStem Cell Reports
December 2024
Laboratorio di Biologia, Scuola Normale Superiore, 56126 Pisa, Italy; Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 56124 Pisa, Italy. Electronic address:
The mechanisms that determine distinct embryonic pallial identities remain elusive. The central role of Wnt signaling in directing dorsal telencephalic progenitors to the isocortex or hippocampus has been elucidated. Here, we show that timely inhibition of MAPK/ERK and BMP signaling in neuralized mouse embryonic stem cells (ESCs) specifies a cell identity characteristic of the allocortex.
View Article and Find Full Text PDFNat Neurosci
January 2025
Department of Neuroscience, University of California, Berkeley, Berkeley, CA, USA.
What is good in one scenario may be bad in another. Despite the ubiquity of such contextual reasoning in everyday choice, how the brain flexibly uses different valuation schemes across contexts remains unknown. We addressed this question by monitoring neural activity from the hippocampus (HPC) and orbitofrontal cortex (OFC) of two monkeys performing a state-dependent choice task.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!