Thalamus Flashcards
Nearly all inputs to the cerebrum synapse first on thalamus neurons.
What are some examples of these inputs?
Sensation, motor/movement, emotions, memory, arousal/consciousness, and attention.
What is the nickname for the Thalamus?
Why is this?
The “switchboard” for the brain.
It is because almost all inputs to the cerebrum first synapse in the thalamus, the thalamus projects axons to almost all of the cortex, and the thalamus gets feedback connections from the cortex.
What are the five groups that thalamus nuclei are organized into?
- Lateral nuclear group
- Medial nuclear group
- Anterior nuclear group
- Intralaminar nuclei
- Nonspecific nuclei
What structure separates the three groups?
What is this structure made of?
The Y shaped “internal medullary lamina” separates the three groups of nuclei.
The internal medullary lamina is made of white matter.
What nuclei are in the Lateral nuclei group?
A. Ventral Posterolateral (VPL) B. Ventral Posteromedial (VPM) C. Lateral Geniculate (LGN) D. Medial Geniculate (MGN) E. Ventral Lateral (VL) F. Ventral Anterior (VA) G. Pulvinar (P)
What nuclei are in the Medial nuclei group?
Mediodorsal Nucleus (MD)
What nuclei are in the Anterior nuclei group?
Anterior Nucleus (AN)
Ventral Posterior Lateral Nuclei (VPL)
- Type
Relay: Sensory
Ventral Posterior Lateral Nuclei (VPL)
- Input
Ascending somatosensory pathways from body
Ventral Posterior Lateral Nuclei (VPL)
- Output
Somatosensory cortex
Ventral Posterior Lateral Nuclei (VPL)
- Function
Relays somatosensation of body to cortex
Ventral Posteromedial Nucleus (VPM)
- Type
Relay: Sensory
Ventral Posteromedial Nucleus (VPM)
- Input
Somatosensory pathways from face / taste
Ventral Posteromedial Nucleus (VPM)
- Output
Somatosensory cortex
Ventral Posteromedial Nucleus (VPM)
- Function
Relays somatosensation from face and taste to cortex
Lateral Geniculate Nucleus (LGN)
- Type
Relay: Sensory
Lateral Geniculate Nucleus (LGN)
- Input
Pathways from retina
Lateral Geniculate Nucleus (LGN)
- Output
Primary visual cortex
Lateral Geniculate Nucleus (LGN)
- Function
Relays visual input to cortex
Medial Geniculate Nucleus (MGN)
- Type
Relay: Sensory
Medial Geniculate Nucleus (MGN)
- Input
Pathways from inferior colliculus
Medial Geniculate Nucleus (MGN)
- Output
Primary auditory cortex
Medial Geniculate Nucleus (MGN)
- Function
Relays auditory information to cortex
Ventral Lateral nucleus (VL)
- Type
Relay: Motor
Ventral Lateral nucleus (VL)
- Input
Motor pathways from cerebellum and basal ganglia
Ventral Lateral nucleus (VL)
- Output
Motor, premotor and supplementary motor cortex
Ventral Lateral nucleus (VL)
- Function
Relays motor information from basal ganglia and cerebellum to cortex
Ventral Anterior nucleus (VA)
- Type
Relay: motor
Ventral Anterior nucleus (VA)
- Input
Motor pathways from cerebellum and basal ganglia
Ventral Anterior nucleus (VA)
- Output
Widespread to frontal lobe including motor areas
Ventral Anterior nucleus (VA)
- Function
Relays motor information from basal ganglia and cerebellum to cortex
Pulvinar (P)
- Type
Association
Pulvinar (P)
- Input
Sensory pathways from tectum
Pulvinar (P)
- Output
Parieto temporal occipital association complex
Pulvinar (P)
- Function
Behavioral orientation to visual stimulus
Mediodorsal nucleus (MD) - Type
Association
Mediodorsal nucleus (MD) - Input
Pathways from limbic structures
Mediodorsal nucleus (MD) - Output
Frontal cortex
Mediodorsal nucleus (MD) - Function
Relay emotional and memory input to cortex
Anterior nucleus (AN) - Type
Association
Anterior nucleus (AN) - Input
Pathways from limbic structures and hippocampus
Anterior nucleus (AN) - Output
Cingulate gyrus
Anterior nucleus (AN) - Function
Relay information within the limbic system
