The role of the human thalamus in processing corollary discharge

The most common neural representations for spatial attention encode locations retinotopically, relative to center of gaze. To keep track of visual objects across saccades or to orient toward sounds, retinotopic representations must be combined with information about the rotation of one's own eyes in the orbits. Although gaze input is critical for a correct allocation of attention, the source of this input has so far remained unidentified. Two main signals are available: corollary discharge (copy of oculomotor command) and oculoproprioception (feedback from extraocular muscles). Here we asked whether the oculoproprioceptive signal relayed from the somatosensory cortex contributes to coding the locus of attention. We used continuous theta burst stimulation (cTBS) over a human oculoproprioceptive area in the postcentral gyrus (S1EYE). S1EYE-cTBS reduces proprioceptive processing, causing ∼1° underestimation of gaze angle. Participants discriminated visual targets whose location was cued in a nonvisual modality. Throughout the visual space, S1EYE-cTBS shifted the locus of attention away from the cue by ∼1°, in the same direction and by the same magnitude as the oculoproprioceptive bias. This systematic shift cannot be attributed to visual mislocalization. Accuracy of open-loop pointing to the same visual targets, a function thought to rely mainly on the corollary discharge, was unchanged. We argue that oculoproprioception is selective for attention maps. By identifying a potential substrate for the coupling between eye and attention, this study contributes to the theoretical models for spatial attention.

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The human thalamus orchestrates neocortical oscillations during NREM sleep.

10.1101/2021.12.11.471766 ◽

2021 ◽

Author(s):

Thomas Schreiner ◽

Elisabeth Kaufmann ◽

Soheyl Noachtar ◽

Jan-Hinnerk Mehrkens ◽

Tobias Staudigl

Keyword(s):

Nrem Sleep ◽

Active Role ◽

Sleep Spindles ◽

Thalamic Nuclei ◽

Human Epilepsy ◽

Anterior Thalamus ◽

Sleep Rhythms ◽

Human Thalamus ◽

Early Phases

A hallmark of non-rapid eye movement (NREM) sleep is the coordinated interplay of slow oscillations (SOs) and sleep spindles. Traditionally, a cortico-thalamo-cortical loop is suggested to coordinate these rhythms: neocortically-generated SOs trigger spindles in the thalamus that are projected back to neocortex. Here, we used direct intrathalamic recordings from human epilepsy patients to test this canonical interplay. We show that SOs in the anterior thalamus precede neocortical SOs, whereas concurrently-recorded SOs in the mediodorsal thalamus are led by neocortical SOs. Furthermore, sleep spindles, detected in both thalamic nuclei, preceded their neocortical counterparts and were initiated during early phases of thalamic SOs. Our findings indicate an active role of the anterior thalamus in organizing the cardinal sleep rhythms in the neocortex and highlight the functional diversity of specific thalamic nuclei in humans. The concurrent coordination of sleep oscillations by the thalamus could have broad implications for the mechanisms underlying memory consolidation.

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The Role of the Parafascicular Complex (CM-Pf) of the Human Thalamus in the Neuronal Mechanisms of Selective Attention

Neuroscience and Behavioral Physiology ◽

10.1007/s11055-006-0015-y ◽

2006 ◽

Vol 36 (3) ◽

pp. 287-295 ◽

Cited By ~ 19

Author(s):

S. N. Raeva

Keyword(s):

Selective Attention ◽

Human Thalamus ◽

Neuronal Mechanisms ◽

Parafascicular Complex

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The Role of Feedback in the Tremor Frequency Activity of Tremor Cells in the Ventral Nuclear Group of Human Thalamus

Advances in Stereotactic and Functional Neurosurgery 7 - Acta Neurochirurgica Supplementum ◽

10.1007/978-3-7091-8909-2_15 ◽

1987 ◽

pp. 54-56 ◽

Cited By ~ 11

Author(s):

F. A. Lenz ◽

S. Schnider ◽

R. R. Tasker ◽

R. Kwong ◽

H. Kwan ◽

...

Keyword(s):

Human Thalamus ◽

Tremor Frequency ◽

Nuclear Group

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Using a classic paper by Bell as a platform for discussing the role of corollary discharge-like signals in sensory perception and movement control

AJP Advances in Physiology Education ◽

10.1152/advan.00080.2013 ◽

2014 ◽

Vol 38 (1) ◽

pp. 12-19

Author(s):

Aaron L. Cecala

Keyword(s):

Electric Fish ◽

Movement Control ◽

Corollary Discharge ◽

Scientific Investigations ◽

Posterior Lateral Line ◽

Neural Substrate ◽

Neurophysiological Data ◽

Afferent Inputs ◽

Classic Paper

Decades of behavioral observations have shown that invertebrate and vertebrate species have the ability to distinguish between self-generated afferent inputs versus those that are generated externally. In the present article, I describe activities focused around the discussion of a classic American Physiological Society paper by Curtis C. Bell that lays the foundation for students to investigate the neural substrate underlying this ability. Students will leave this activity being able to 1) describe the technical aspects and limitations of an electric fish preparation commonly used to acquire single unit (extracellular) neurophysiological data, 2) provide physiological evidence showing that the activity of principal cells in the posterior lateral line lobe of the electric fish brain reflects that of a reafference comparator that could be used in dissociating self-generated versus externally generated sensory signals, and 3) knowledgeably discuss hypotheses concerning the role of corollary discharge and cerebellar-like structures in vertebrate and invertebrate species. The skills and background knowledge gained in this activity lay the platform for advanced study of scientific investigations into sensory, motor, and cognitive processes in undergraduate, graduate, or medical school curricula.

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