Thalamic Gating Research Articles

Does the form of akinetic mutism linked to mesodiencephalic injuries bridge the double dissociation of Parkinson's disease and catatonia?

Northoff provides a compelling argument supporting a kind of “double dissociation” of Parkinson's disease and catatonia. We discuss a related form of akinetic mutism linked to mesodiencephalic injuries and suggest an alternative to the proposed “horizontal” versus “vertical” modulation distinction. Rather than a “directional” difference in patterned neuronal activity, we propose that both disorders reflect hypersynchrony within typically interdependent but segregated networks facilitated by a common thalamic gating mechanism.

Transformation from temporal to rate coding in a somatosensory thalamocortical pathway.

The anatomical connections from the whiskers to the rodent somatosensory (barrel) cortex form two parallel (lemniscal and paralemniscal) pathways. It is unclear whether the paralemniscal pathway is directly involved in tactile processing, because paralemniscal neuronal responses show poor spatial resolution, labile latencies and strong dependence on cortical feedback. Here we show that the paralemniscal system can transform temporally encoded vibrissal information into a rate code. We recorded the representations of the frequency of whisker movement along the two pathways in anaesthetized rats. In response to varying stimulus frequencies, the lemniscal neurons exhibited amplitude modulations and constant latencies. In contrast, paralemniscal neurons in both thalamus and cortex coded the input frequency as changes in latency. Because the onset latencies increased and the offset latencies remained constant, the latency increments were translated into a rate code: increasing onset latencies led to lower spike counts. A thalamocortical loop that includes cortical oscillations and thalamic gating can account for these results. Thus, variable latencies and effective cortical feedback in the paralemniscal system can serve the processing of temporal sensory cues, such as those that encode object location during whisking. In contrast, fixed time locking in the lemniscal system is crucial for reliable spatial processing.

Pharmacology of sensory gating in the ascending auditory system of the pigeon (Columba livia).

Whether the underlying neurochemical basis of sensori(motor) gating is exclusively the result of mammalian brain evolution is not known. The effects of ketamine (KET), benztropine (BTP), apomorphine (APO), methylphenidatehydrochloride (AMP) and haloperidol (HAL) on sensorimotor gating of the acoustic startle and gating of auditory input into the telelencephalon was assessed in a within-subject design in pigeons (Columba livia) using the prepulse inhibition (PPI) paradigm. The startle blink reflex was recorded using EMG electrodes which were chronically implanted into the adjoining Musculus palpepralis superior et inferior, Musculus elevator palpebralis superior, and Musculus nictitantis. Thalamic gating was recorded using electrodes which were chronically implanted into the nucleus ovoidalis thalami and the neostriatum caudale (field L), respectively. KET, APO and AMP disrupted dose-dependently sensorimotor gating. The effect of APO and AMP was blocked by HAL. PPI disruption following BTP did not reach statistical significance. KET disrupted thalamic gating and increased prepulse-induced inhibition in field L. By contrast, AMP increased thalamic and decreased field L inhibition of field potentials when preceded by a pre-stimulus. Both effects were antagonised by HAL thus providing preliminary evidence for a D2-mediated auditory gating mechanism in the thalamus. However, while the effect of APO at the thalamic level was similar to AMP, prepulse-induced inhibition of field L activity was enhanced. This may be explained by concurrent D1-mediated telencephalic inhibition. It is concluded that thalamic gating is modulated by a dopaminergic/glutamatergic mechanism. The findings also confirm the notion of an homologous neurochemical basis of sensorimotor gating in mammals and birds.

Subcortical Aphasia

We critically review the literature on subcortical aphasia, suggest that a number of traditional concepts regarding mechanisms of aphasia are inconsistent with now abundant data, and propose several new hypotheses. The absence of aphasia in 17 reported cases of dominant hemisphere striatocapsular infarction and the finding of nearly every conceivable pattern of language impairment in 33 different reported cases of striatocapsular infarction provide strong evidence against a major direct role of the basal ganglia in language and against disconnection or diaschisis as mechanisms of nonthalamic subcortical aphasia. However, detailed consideration of the vascular events leading to striatocapsular infarction strongly suggests that associated linguistic deficits are predominantly related to sustained cortical hypoperfusion and infarction not visible on structural imaging studies. Thalamic disconnection, as may occur with striatocapsular infarcts with extension to the temporal stem and putamenal hemorrhages, may also contribute to the language deficits in some patients. Review of the literature on thalamic infarction, in conjunction with previously unreported anatomic details of four cases, suggests that what infarcts in the tuberothalamic artery territory and the occasional infarcts in the paramedian artery territory associated with aphasia have in common is damage to the frontal lobe–inferior thalamic peduncle–nucleus reticularis–center median system that may be involved in regulating the thalamic gate in attentional processes. Disruption of attentional gating in the pulvinar and lateral posterior nuclei resulting from such lesions may impair selection of specific neuronal networks in the projection field of these nuclei that serve as the substrate for lexical–semantic function, which is in effect a disruption of a type of working memory, as defined by Goldman–Rakic. We define this as a defect of selective engagement.

Altered consciousness: pharmacology and phenomenology BAP Summer Meeting, York, July 1991

In this article parallels are drawn between sleep and anaesthesia. Both can be described as 'behavioural states' in which stimulation and inhibition of certain neuronal groups will give rise to specific psychological states. The neuronal mechanisms leading to these states are reviewed and compared. Sensory information flow through the thalamus is reduced in sleep and anaesthesia, the thalamic gating being controlled by other areas of the brain including the sensory cortex. Thus a feedback loop may exist with the brain determining its own level of arousal. Anaesthesia increases gating at the thalamus and thus specifically reduces arousal. Consciousness is a specific attribute of the brain and is not required for the processing of sensory stimuli and learning, both of which have been shown to occur during sleep and anaesthesia. The implications of these findings for monitoring awareness during anaesthesia are discussed.

Blockade of frontocortical-brain stem pathway prevents ventricular fibrillation of ischemic heart.

The hypothesis tested was that functional blockade of a pathway known to travel from the frontal cortex through the posterior hypothalamus to the brain stem might prevent the occurrence of ventricular fibrillation (VF) in the ischemic heart of conscious stressed pigs. The hypothesis was based on previous findings that 1) psychological stress is a necessary factor for the initiation of VF in the ischemic heart of conscious pigs, 2) the frontal cortex and its related thalamic gating mechanism, uniquely show neuroelectric responses to stressful stimuli, and 3) direct electric stimulation of either the frontal cortex, posterior hypothalamus, or fields of Forel will produce ventricular arrhythmias and myocardial necrosis. In the present study it was found that cryogenic blockade of the forebrain, posterior hypothalamus, or fields of Forel prevents or delays VF after left anterior descending coronary artery occlusion in conscious stressed pigs (P less than 0.01). Blockade of control structures adjacent to these loci in another group of pigs had no effect on VF latency. Neither heart rate nor electroencephalographic changes could explain the differences between the groups. The results show that blockade of the frontocortical-brain stem pathway prevents the lethal consequences of myocardial ischemia in stressed animals.

An analysis of the activation of motor cortical neurons by surface stimulation.

An analysis of the activation of motor cortical neurons by surface stimulation.J Rosenthal, H J Waller, and V E AmassianJ Rosenthal, H J Waller, and V E AmassianPublished Online:01 Jul 1967https://doi.org/10.1152/jn.1967.30.4.844MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByPhase-Locked Stimulation during Cortical Beta Oscillations Produces Bidirectional Synaptic Plasticity in Awake MonkeysCurrent Biology, Vol. 28, No. 16Ongoing brain rhythms shape I-wave properties in a computational modelBrain Stimulation, Vol. 11, No. 4Noninvasive Stimulation of the Human Brain: Activation of Multiple Cortical Circuits29 June 2017 | The Neuroscientist, Vol. 24, No. 3Heavy alcohol use in adolescence is associated with altered cortical activity: a combined TMS-EEG study23 December 2016 | Addiction Biology, Vol. 23, No. 1Transcranial Magnetic Stimulation-Electroencephalography Responses in Recovered and Symptomatic Mild Traumatic Brain InjuryJournal of Neurotrauma, Vol. 30, No. 14Time-frequency analysis of short-lasting modulation of EEG induced by intracortical and transcallosal paired TMS over motor areasPaolo Manganotti, Emanuela Formaggio, Silvia Francesca Storti, Daniele De Massari, Alessandro Zamboni, Alessandra Bertoldo, Antonio Fiaschi, and Gianna Maria Toffolo1 May 2012 | Journal of Neurophysiology, Vol. 107, No. 9Effects of Botulinum Toxin on Central Nervous System FunctionPerception of Phosphenes and Flashed Alphabetical Characters is Enhanced by Single-Pulse Transcranial Magnetic Stimulation of Anterior Frontal Lobe: The Thalamic Gate Hypothesis1 January 2008 | Perception, Vol. 37, No. 3Column-based model of electric field excitation of cerebral cortex1 January 2004 | Human Brain Mapping, Vol. 22, No. 1Distinct differences in cortical reactivity of motor and prefrontal cortices to magnetic stimulationClinical Neurophysiology, Vol. 115, No. 3Direct recording of the output of the motor cortex produced by transcranial magnetic stimulation in a patient with cerebral cortex atrophyClinical Neurophysiology, Vol. 115, No. 1Modulation of electroencephalographic responses to transcranial magnetic stimulation: evidence for changes in cortical excitability related to movementEuropean Journal of Neuroscience, Vol. 18, No. 5Alcohol Reduces Prefrontal Cortical Excitability in Humans: A Combined TMS and EEG Study23 October 2002 | Neuropsychopharmacology, Vol. 28, No. 4Clinical and Research Methods for Evaluating Cortical ExcitabilityJournal of Clinical Neurophysiology, Vol. 19, No. 4I-Waves in Motor CortexJournal of Clinical Neurophysiology, Vol. 17, No. 4Transcranial Magnetic Stimulation in Study of the Visual PathwayJournal of Clinical Neurophysiology, Vol. 15, No. 4The polarity of the induced electric field influences magnetic coil inhibition of human visual cortex: implications for the site of excitationElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 93, No. 1Cortical and spinal motor excitability during the transcranial magnetic stimulation silent period in humansBrain Research, Vol. 628, No. 1-2Unmasking human visual perception with the magnetic coil and its relationship to hemispheric asymmetryBrain Research, Vol. 605, No. 2Measurement of information processing delays in human visual cortex with repetitive magnetic coil stimulationBrain Research, Vol. 605, No. 2The muscle silent period following transcranial magnetic cortical stimulationJournal of the Neurological Sciences, Vol. 114, No. 2Enhancement of the amplitude of somatosensory evoked potentials following magnetic pulse stimulation of the human brainElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 88, No. 1Modelling magnetic coil excitation of human cerebral cortex with a peripheral nerve immersed in a brain-shaped volume conductor: the significance of fiber bending in excitationElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 85, No. 5Inhibitory period following motor potentials evoked by magnetic cortical stimulationElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 85, No. 4Motor potentials evoked in tibialis anterior by single and paired cervical stimuli in manNeuroscience Letters, Vol. 125, No. 2Corticospinal responses to electrical stimulation of motor cortex in the ratBrain Research, Vol. 508, No. 2Focal stimulation of human cerebral cortex with the magnetic coil: a comparison with electrical stimulationElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 74, No. 6Suppression of visual perception by magnetic coil stimulation of human occipital cortexElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 74, No. 6The effect of experimental ischaemia on the direct cortical response of the motor cortex in primatesElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 71, No. 4Non-invasive evaluation of input-output characteristics of sensorimotor cerebral areas in healthy humansElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 68, No. 2Neuronal activity evoked by chronically implanted intracortical microelectrodesExperimental Neurology, Vol. 92, No. 1Nervous propagation along ‘central’ motor pathways in intact man: Characteristics of motor responses to ‘bifocal’ and ‘unifocal’ spine and scalp non-invasive stimulationElectroencephalography and Clinical Neurophysiology, Vol. 61, No. 4Which elements are excited in electrical stimulation of mammalian central nervous system: A reviewBrain Research, Vol. 98, No. 3Basic mechanisms of magnetic coil excitation of nervous system in humans and monkeys and their applicationsCallosal and non-callosal connexions between the sensory-motor cortices in cat and monkeyElectroencephalography and Clinical Neurophysiology, Vol. 26, No. 6Electrophysiology of “epileptic” neurons: Spike generationElectroencephalography and Clinical Neurophysiology, Vol. 26, No. 5 More from this issue > Volume 30Issue 4July 1967Pages 844-58 https://doi.org/10.1152/jn.1967.30.4.844PubMed6035693History Published online 1 July 1967 Published in print 1 July 1967 Metrics

PRODUCTION OF THRESHOLD LEVELS OF CONSCIOUS SENSATION BY ELECTRICAL STIMULATION OF HUMAN SOMATOSENSORY CORTEX.

ArticlesPRODUCTION OF THRESHOLD LEVELS OF CONSCIOUS SENSATION BY ELECTRICAL STIMULATION OF HUMAN SOMATOSENSORY CORTEXB. Libet, W. W. Alberts, E. W. Wright JR., L. D. Delattre, G. Levin, and B. FeinsteinB. Libet, W. W. Alberts, E. W. Wright JR., L. D. Delattre, G. Levin, and B. FeinsteinPublished Online:01 Jul 1964https://doi.org/10.1152/jn.1964.27.4.546MoreSectionsPDF (5 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByUtility and safety of depth electrodes within the supratemporal plane for intracranial EEG7 September 2018 | Journal of Neurosurgery, Vol. 2Temporal recalibration of motor and visual potentials in lag adaptation in voluntary movementNeuroImage, Vol. 172Brain-Machine Interfaces: From Basic Science to Neuroprostheses and NeurorehabilitationMikhail A. Lebedev and Miguel A. L. Nicolelis8 March 2017 | Physiological Reviews, Vol. 97, No. 2Perception of Phosphenes and Flashed Alphabetical Characters is Enhanced by Single-Pulse Transcranial Magnetic Stimulation of Anterior Frontal Lobe: The Thalamic Gate Hypothesis1 January 2008 | Perception, Vol. 37, No. 3On the Alleged Illusion of Conscious Will21 August 2006 | Philosophical Psychology, Vol. 18, No. 6Brain stimulation and conscious experienceConsciousness and Cognition, Vol. 13, No. 3The sense of movement elicited by transcranial magnetic stimulation in humans is due to sensory feedback13 April 2004 | The Journal of Physiology, Vol. 556, No. 2Inferior central sulcus: variations of anatomy and function on the example of the motor tongue areaNeuroImage, Vol. 20, No. 1Consciousness15 April 2003Time Course and Magnitude of Movement-Related Gating of Tactile Detection in Humans. III. Effect of Motor TasksStephan R. Williams, and C. Elaine Chapman1 October 2002 | Journal of Neurophysiology, Vol. 88, No. 4On Subjective Back-Referral and How Long It Takes to Become Conscious of a Stimulus: A Reinterpretation of Libet's DataConsciousness and Cognition, Vol. 11, No. 2Problems in the Timing of Conscious ExperienceConsciousness and Cognition, Vol. 11, No. 2A Neural Correlate of Consciousness Related to RepressionConsciousness and Cognition, Vol. 11, No. 2The Timing of Mental Events: Libet's Experimental Findings and Their ImplicationsConsciousness and Cognition, Vol. 11, No. 2Real Latencies and FacilitationConsciousness and Cognition, Vol. 11, No. 2Commentary on Shevrin, Ghannam, and Libet, “A Neural Correlate of Consciousness Related to Repression”Consciousness and Cognition, Vol. 11, No. 2Train Duration Effects on Perception: Sensory Deficit, Neglect, and Cerebral LateralizationJournal of Clinical Neurophysiology, Vol. 17, No. 4Transcranial Magnetic Stimulation in Study of the Visual PathwayJournal of Clinical Neurophysiology, Vol. 15, No. 4Magnetic Stimulation of Visual Cortex: Factors Influencing the Perception of PhosphenesJournal of Clinical Neurophysiology, Vol. 15, No. 4Breakthrough to awareness: a preliminary neural network model of conscious and unconscious perception in word processingBiological Cybernetics, Vol. 75, No. 1Differentiation of sensorimotor neuronal structures responsible for induction of motor evoked potentials, attenuation in detection of somatosensory stimuli, and induction of sensation of movement by mapping of optimal current directionsElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 93, No. 3Evaluation of the actions of general anaesthetics in the human brainGeneral Pharmacology: The Vascular System, Vol. 23, No. 6Altered consciousness: pharmacology and phenomenology BAP Summer Meeting, York, July 19911 July 2016 | Journal of Psychopharmacology, Vol. 6, No. 3Focal stimulation of human cerebral cortex with the magnetic coil: a comparison with electrical stimulationElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 74, No. 6Suppression of visual perception by magnetic coil stimulation of human occipital cortexElectroencephalography and Clinical Neurophysiology/Evoked Potentials Section, Vol. 74, No. 6A sense of movement elicited in paralyzed distal arm by focal magnetic coil stimulation of human motor cortexBrain Research, Vol. 479, No. 2Roles for perceived voluntary motor commands in motor controlTrends in Neurosciences, Vol. 10, No. 2The effect of postcentral cortical lesions on motor responses to sudden upper limb displacements in monkeysBrain Research, Vol. 96, No. 1A Prosthesis for the Deaf Based on Cortical Stimulation28 June 2016 | Annals of Otology, Rhinology & Laryngology, Vol. 82, No. 4Functions of the mammalian cerebral cortex in movementProgress in Neurobiology, Vol. 1Paresthesias and EEG potentials evoked by stimulation of the dorsal funiculi in manExperimental Neurology, Vol. 36, No. 2On columnar arrangement of nerve cells in cerebral cortexBrain Research, Vol. 27, No. 1Localization and habituation of sensory evoked DC responses in cat cortexExperimental Neurology, Vol. 15, No. 4 More from this issue > Volume 27Issue 4July 1964Pages 546-578 https://doi.org/10.1152/jn.1964.27.4.546PubMed14194958History Published online 1 July 1964 Published in print 1 July 1964 Metrics