Dorsal “Thalamus”
Medical Neuroscience Dr. Wiegand
The Diencephalon
The Diencephalon
InterthalamicInterthalamic adhesionadhesion
ThalamusThalamus EpithalamusEpithalamus HypothalamusHypothalamus (Pineal(Pineal & & Habenula)Habenula) PituitaryPituitary SubthalamusSubthalamus
1 The “Dorsal” Thalamus
| Sensory integration nucleus – gateway to the cerebral cortex | Afferents from both rostral and caudal central nervous system structures | Efferents primarily to cerebral cortex via four principal “radiations” | Associated with motor, sensory, limbic and vegetative functions
External medullary lamina Anterior n.
3rd Internal capsule Internal Ventricle Medial n. Medial Lateral n. Internal capsule
* Reticular n. Internal * Interthalamic adhesion medullary lamina
2 General Organization
medialmedial nuclei nuclei anterioranterior nuclei nuclei
internalinternal medullarymedullary laminalamina laterallateral nuclei nuclei
dorsaldorsal tier tier
pulvinarpulvinar
geniculategeniculate ventralventral tier tier bodiesbodies
Frontal Section
intralaminarintralaminar nucleinuclei
reticularreticular nuclei nuclei 3rd Ventricle
externalexternalexternalexternal medullarymedullary laminalamina internalinternal laminalamina medullarymedullary laminalamina
3 Thalamic Nuclei
| Anterior | Lateral z Dorsal Tier • lateral dorsal • lateral posterior • pulvinar z Ventral Tier • ventral anterior • ventral lateral • ventral posterior (VLP & VPM) • posterior nucleus
Thalamic Nuclei
| Medial z medial/medial dorsal z midline nuclei | Pulvinar | Geniculate bodies | Reticular | Intralaminar z centromedian z parafasciular
Specific Sensory Nuclei
afferent nucleus efferent function Dorsal VPL Postcentral Somesthesis Column & Gyrus Anterolateral System Trigeminal VPM Postcentral Somesthesis System Gyrus Inferior MGB Temporal Hearing Colliculus lobe Retina LGB Occipital Vision lobe
4 Specific Cortical Relay Nuclei
afferent nucleus efferent function Cerebellum VL Precentral Movement & Gyrus & Motor Planning Frontal cortex Globus VA Premotor Motor Planning Pallidus Cortex
Specific Association Nuclei afferent nucleus efferent function Hypothalamus Anterior Cingulate Limbic Amygdala MD Prefrontal Limbic Cortex Hypothalamus LD Cingulate Emotions & Cingulate Parietal lobe & LP Parietal Cortex Sensory Sup.Colliculus integration Anterolateral Posterior Insula, Pain System Cingulate and Association Cortices Sup. Pulvinar Temporal, Vision Colliculus Parietal and Occipital Lobes
Non-Specific Nuclei
afferent nucleus efferent function Reticular Midline Entire Cortex Arousal/Limbic Formation Motor / Intra- Striatum & Motor Premotor laminar Cortex Integration Basal Ganglia & Reticular Formation Cortex & Reticular Thalamus Thalamic Brainstem Modulation
5 CaudateCaudate Nucleus Nucleus
Internal LentiformLentiform Nuclei Nuclei Capsule
ThalamusThalamus
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