Single-neuron correlates of subjective vision in the human medial temporal lobe
- *Computation and Neural Systems Program, California Institute of Technology 139-74, Pasadena, CA 91125; †Division of Neurosurgery, University of California School of Medicine, Los Angeles, CA 90095; and §Department of Behavioral Sciences and Psychiatry, Functional Neurosurgery Unit, Tel-Aviv Medical Center and Sackler School of Medicine, Tel-Aviv University, Tel-Aviv 69978, Israel
-
Communicated by Francis Crick, The Salk Institute for Biological Studies, San Diego, CA (received for review March 15, 2002)
Abstract
Visual information from the environment is transformed into perceptual sensations through several stages of neuronal processing. Flash suppression constitutes a striking example in which the same retinal input can give rise to two different conscious visual percepts. We directly recorded the responses of individual neurons during flash suppression in the human amygdala, entorhinal cortex, hippocampus, and parahippocampal gyrus, allowing us to explore the neuronal responses in untrained subjects at a high spatial and temporal resolution in the medial temporal lobe. Subjects were patients with pharmacologically intractable epilepsy implanted with depth electrodes to localize the seizure onset focus. We observed that the activity of two thirds of all visually selective neurons followed the perceptual alternations rather than the retinal input. None of the selective neurons responded to a perceptually suppressed stimulus. Therefore, the activity of most individual neurons in the medial temporal lobe of naive human subjects directly correlates with the phenomenal visual experience.
Abbreviation
- MTL,
- medial temporal lobe
- Received March 15, 2002.
- Accepted April 2, 2002.
- Copyright © 2002, The National Academy of Sciences
