Browsing by Author "Sommer, Marc A"
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A pathway in primate brain for internal monitoring of movements.
Sommer, Marc A; Wurtz, Robert H (Science, 2002-05-24)It is essential to keep track of the movements we make, and one way to do that is to monitor correlates, or corollary discharges, of neuronal movement commands. We hypothesized that a previously identified pathway from brainstem ... -
Activity of neurons in monkey globus pallidus during oculomotor behavior compared with that in substantia nigra pars reticulata.
Shin, SooYoon; Sommer, Marc A (J Neurophysiol, 2010-04)The basal ganglia are a subcortical assembly of nuclei involved in many aspects of behavior. Three of the nuclei have high firing rates and inhibitory influences: the substantia nigra pars reticulata (SNr), globus pallidus ... -
Advances in understanding mechanisms of thalamic relays in cognition and behavior.
Mitchell, Anna S; Sherman, S Murray; Sommer, Marc A; Mair, Robert G; Vertes, Robert P; Chudasama, Yogita (J Neurosci, 2014-11-12)The main impetus for a mini-symposium on corticothalamic interrelationships was the recent number of studies highlighting the role of the thalamus in aspects of cognition beyond sensory processing. The thalamus contributes ... -
Application of long-interval paired-pulse transcranial magnetic stimulation to motion-sensitive visual cortex does not lead to changes in motion discrimination.
Gamboa, Olga Lucia; Brito, Alexandra; Abzug, Zachary; D'Arbeloff, Tracy; Beynel, Lysianne; Wing, Erik A; Dannhauer, Moritz; ... (17 authors) (Neuroscience letters, 2020-05-12)The perception of visual motion is dependent on a set of occipitotemporal regions that are readily accessible to neuromodulation. The current study tested if paired-pulse Transcranial Magnetic Stimulation (ppTMS) could modulate ... -
Brain circuits for the internal monitoring of movements.
Sommer, Marc A; Wurtz, Robert H (Annu Rev Neurosci, 2008)Each movement we make activates our own sensory receptors, thus causing a problem for the brain: the spurious, movement-related sensations must be discriminated from the sensory inputs that really matter, those representing ... -
Cognitive control of movement via the cerebellar-recipient thalamus.
Prevosto, Vincent; Sommer, Marc A (Front Syst Neurosci, 2013-10-01)The cognitive control of behavior was long considered to be centralized in cerebral cortex. More recently, subcortical structures such as cerebellum and basal ganglia have been implicated in cognitive functions as well. ... -
Corollary discharge across the animal kingdom.
Crapse, Trinity B; Sommer, Marc A (Nat Rev Neurosci, 2008-08)Our movements can hinder our ability to sense the world. Movements can induce sensory input (for example, when you hit something) that is indistinguishable from the input that is caused by external agents (for example, when ... -
Corollary discharge circuits in the primate brain.
Crapse, Trinity B; Sommer, Marc A (Curr Opin Neurobiol, 2008-12)Movements are necessary to engage the world, but every movement results in sensorimotor ambiguity. Self-movements cause changes to sensory inflow as well as changes in the positions of objects relative to motor effectors ... -
Delay activity of saccade-related neurons in the caudal dentate nucleus of the macaque cerebellum.
Ashmore, Robin C; Sommer, Marc A (J Neurophysiol, 2013-04)The caudal dentate nucleus (DN) in lateral cerebellum is connected with two visual/oculomotor areas of the cerebrum: the frontal eye field and lateral intraparietal cortex. Many neurons in frontal eye field and ... -
Division of labor in frontal eye field neurons during presaccadic remapping of visual receptive fields.
Shin, Sooyoon; Sommer, Marc A (J Neurophysiol, 2012-10)Our percept of visual stability across saccadic eye movements may be mediated by presaccadic remapping. Just before a saccade, neurons that remap become visually responsive at a future field (FF), which anticipates the saccade ... -
Drivers from the deep: the contribution of collicular input to thalamocortical processing.
Wurtz, Robert H; Sommer, Marc A; Cavanaugh, James (Prog Brain Res, 2005)A traditional view of the thalamus is that it is a relay station which receives sensory input and conveys this information to cortex. This sensory input determines most of the properties of first order thalamic neurons, ... -
Dynamics of visual receptive fields in the macaque frontal eye field.
Mayo, J Patrick; DiTomasso, Amie R; Sommer, Marc A; Smith, Matthew A (J Neurophysiol, 2015-12)Neuronal receptive fields (RFs) provide the foundation for understanding systems-level sensory processing. In early visual areas, investigators have mapped RFs in detail using stochastic stimuli and sophisticated analytical ... -
Evaluating the effects of image persistence on dynamic target acquisition in low frame rate virtual environments
Zielinski, David J; Rao, Hrishikesh M; Potter, Nicholas D; Sommer, Marc A; Appelbaum, Lawrence G; Kopper, Regis (2016 IEEE Symposium on 3D User Interfaces, 3DUI 2016 - Proceedings, 2016-04-26)© 2016 IEEE.User performance in virtual environments with degraded visual conditions due to low frame rates is an interesting area of inquiry. Visual content shown in a low frame rate simulation has the quality of the original ... -
Exploring the effects of image persistence in low frame rate virtual environments
Zielinski, David J; Rao, Hrishikesh M; Sommer, Marc A; Kopper, Regis (2015 IEEE Virtual Reality Conference, VR 2015 - Proceedings, 2015-08-25)© 2015 IEEE.In virtual reality applications, there is an aim to provide real time graphics which run at high refresh rates. However, there are many situations in which this is not possible due to simulation or rendering ... -
Frontal eye field neurons assess visual stability across saccades.
Crapse, Trinity B; Sommer, Marc A (J Neurosci, 2012-02-22)The image on the retina may move because the eyes move, or because something in the visual scene moves. The brain is not fooled by this ambiguity. Even as we make saccades, we are able to detect whether visual objects remain ... -
Frontal eye field neurons with spatial representations predicted by their subcortical input.
Crapse, Trinity B; Sommer, Marc A (J Neurosci, 2009-04-22)The frontal eye field (FEF) is a cortical structure involved in cognitive aspects of eye movement control. Neurons in the FEF, as in most of cerebral cortex, primarily represent contralateral space. They fire for visual ... -
Identifying corollary discharges for movement in the primate brain.
Wurtz, Robert H; Sommer, Marc A (Prog Brain Res, 2004)The brain keeps track of the movements it makes so as to process sensory input accurately and coordinate complex movements gracefully. In this chapter we review the brain's strategies for keeping track of fast, saccadic ... -
Influence of the thalamus on spatial visual processing in frontal cortex.
Sommer, Marc A; Wurtz, Robert H (Nature, 2006-11-16)Each of our movements activates our own sensory receptors, and therefore keeping track of self-movement is a necessary part of analysing sensory input. One way in which the brain keeps track of self-movement is by monitoring ... -
Intensity- and timing-dependent modulation of motion perception with transcranial magnetic stimulation of visual cortex.
Gamboa Arana, Olga Lucia; Palmer, Hannah; Dannhauer, Moritz; Hile, Connor; Liu, Sicong; Hamdan, Rena; Brito, Alexandra; ... (12 authors) (Neuropsychologia, 2020-10)Despite the widespread use of transcranial magnetic stimulation (TMS) in research and clinical care, the dose-response relations and neurophysiological correlates of modulatory effects remain relatively unexplored. To fill ... -
Metacognition in monkeys during an oculomotor task.
Middlebrooks, Paul G; Sommer, Marc A (J Exp Psychol Learn Mem Cogn, 2011-03)This study investigated whether rhesus monkeys show evidence of metacognition in a reduced, visual oculomotor task that is particularly suitable for use in fMRI and electrophysiology. The 2-stage task involved punctate visual ...