Publications by authors named "Xavier Celaya"

Words represent a uniquely human information channel-humans use words to express thoughts and feelings and to assign emotional valence to experience. Work from model organisms suggests that valence assignments are carried out in part by the neuromodulators dopamine, serotonin, and norepinephrine. Here, we ask whether valence signaling by these neuromodulators extends to word semantics in humans by measuring sub-second neuromodulator dynamics in the thalamus (N = 13) and anterior cingulate cortex (N = 6) of individuals evaluating positive, negative, and neutrally valenced words.

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The noradrenaline (NA) system is one of the brain's major neuromodulatory systems; it originates in a small midbrain nucleus, the locus coeruleus (LC), and projects widely throughout the brain. The LC-NA system is believed to regulate arousal and attention and is a pharmacological target in multiple clinical conditions. Yet our understanding of its role in health and disease has been impeded by a lack of direct recordings in humans.

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Latent variable analyses of cognitive abilities are among the major means by which cognitive psychologists test theories regarding the structure of human cognition. Models are fit to observed variance-covariance structures, and the fit of those models are compared to assess the merits of competing theories. However, an often unconsidered and potentially important methodological issue is the precise sequence in which tasks are delivered to participants.

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