title: Neural coding and perceptual detection in the primate somatosensory thalamus.
abstract: The contribution of the sensory thalamus to perception and decision making is not well understood. We addressed this problem by recording single neurons in the ventral posterior lateral (VPL) nucleus of the somatosensory thalamus while trained monkeys judged the presence or absence of a vibrotactile stimulus of variable amplitude applied to the skin of a fingertip. We found that neurons in the VPL nucleus modulated their firing rate as a function of stimulus amplitude, and that such modulations accounted for the monkeys' overall psychophysical performance. These neural responses did not predict the animals' decision reports in individual trials, however. Moreover, the sensitivity to changes in stimulus amplitude was similar when the monkeys' performed the detection task and when they were not required to report stimulus detection. These results suggest that the primate somatosensory thalamus likely provides a reliable neural representation of the sensory input to the cerebral cortex, where sensory information is transformed and combined with other cognitive components associated with behavioral performance.
authors.affiliation: Instituto de Fisiología Celular-Neurociencias, Universidad Nacional Autónoma de México, 04510 Mexico DF, Mexico.
authors.forename: Yuriria
authors.initials: Y
authors.lastname: Vázquez
authors.forename: Antonio
authors.initials: A
authors.lastname: Zainos
authors.forename: Manuel
authors.initials: M
authors.lastname: Alvarez
authors.forename: Emilio
authors.initials: E
authors.lastname: Salinas
authors.forename: Ranulfo
authors.initials: R
authors.lastname: Romo
mesh_terms: D000818:Animals; D003657:Decision Making / Q000502:physiology*; D008253:Macaca mulatta; D008839:Microelectrodes; D009474:Neurons; D010812:Physical Stimulation; D011597:Psychomotor Performance; D011601:Psychophysics; D012372:ROC Curve; D013788:Thalamus / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*; D020651:Ventral Thalamic Nuclei / Q000166:cytology*