Thalamus Anatomy Flashcards
Most ventral part of Diencephalon
Hypothalamus
Medial boundary of thalamus
3rd ventricle
Division of Diencephalon
Epithalamus
Ventral thalamus
Dorsal Thalamus
Largest thalamic division
Dorsal thalamus
Pineal and habenular nuclei belongs to what division of thalamus
Epithalamus
Location of pulvinar nucleus
dorsal to MGB and LGB
What separates caudate nucleus to pulvinar nucleus
Stria Medullaris
This is a 2 gray masses forming triangular eminence on dorsomedial surface of thalamus
Habenular nuclei
This margin is the attachment of stria medullaris to habenular nuclei
Tenia Thalami
What is the only nucleus that terminates exclusively in the medial interpeduncular nucleus
Habenular nuclei
What are the fibers that arise in Stria medullaris
Anterior thalamic nuclei
Lateral pre-optic nuclei
Septal Nuclei
Function of the later habenular nucleui
Functional interface between limbic and motor system
Function of Medial habenuclar nuclei
Contains cholinergic neurons
Melatonin is secreted from
Serotonin
This is a neurosensory photoreceptor elements that become predominantly secretory cells
Pinelocytes
Location of Pineal gland
Roof of 3rd ventricle in the posterior commisure
This separates anterior, medial and lateral nuclear thalamic groups
Hypothalamic sulcus
Centromedian belong to what nuclear group
intralaminar nuclear group
Lateral nuclear group is divided to
Ventral and Dorsal
Ventral nuclear group includes:
VPN VLB and VA
Dorsal thalamic nucleus include
Pulvinar
Lateral posterior
Lateral dorsal nucleus
This nucleus contains the mediodorsal nucleus
Medial nuclear groul
MDN is related to what structure
frontal lobe
What structure separates by internal medullary lamina
Splits to surround the centromedian into 2 halves (mediodorsal)
This nucleus is located outside the external medullar band
Reticular nucleus of thalamus
This pertains to Metathalamus
LGB and MGB
Anterior nuclear groups location
Dorsal surface of the most rostral part of thalamus
Direct hippocampal projection
Fornix to Thalamus
Function of anterior nuclear group
Critical for encoding memory and sustaining attention
Medial Nuclear Group includes
Mediodorsal and Dorsomedial
This nuclei occupies the most area between internal medullary lamina and periventricular gray matter
Mediodorsal nucleus
Major source of basal forebrain afferent of mediodorsal nucleus
Ventral pallidum
Ansa peduncularis consist of
Inferior thalamic peduncle
Fibers of amygdaloid complex
Preopticohypothalamic region
Lesion of Mediodorsal nucleus
Decrease emotional responsiveness and anterograde amnesia
These are nuclei within the internal medullar lamina
Intralaminar Nuclear Groups
Includes the Intralaminar nuclear groups (Rostral)
Paracentral nucleus
Central lateral nucleus
Central Nucleus
Internal medullary lamina completely surrounded the centromedian nucleus except
Medial borders
location of centromedian nucleus
Between DMN and VP nucleus
Intralaminar nuclei will project to what layer of the cortex
V
Heavy thalamic projection of the GPi
centromedian
Thalamic projection of Deep Cerebellar Nuclei
Central lateral
Parafascicular
Lateral Dorsal Nucleus projects to what area
Posterior parietal cortex
Posterior cingulate
This is a thalamic nucleus that has no myelin fiber
Lateral posterior nucleus
Division of Pulvinar Nucleus
Pars oralis - between VPL and CM
Pars inferior - between MGB and LGB
Pars lateralis - along the ELM
Pars medialis - medial half of pulvinar
Afferent of pulvinar nucleus
Superior colliculus (superficial layer)
Projection of pulvinar nucleus
Inferior pulvinar - Area 17 and 18 (extrageniculate)
Lateral pulvinar - temporal cortex
Medial Pulvinar - Superior temporal gyrus and inferior parietal lobule
What innervates Parvicellular Ventral Anterior
GPi
What innervates VAmc
Substantia Nigra
Connection of the following
Area 6
Area 8
Area 6 : VApc
Area 8 : VAmc
Major pallidal projection of ventrolateral nucleus
Pars oralis (VLo) Pars medialis (VLm)
This is the largest somatic relay nucleus of thalamus
Ventral Posterior
Other name for Ventral Posterior
Ventrobasal complex
2 division of VPL
VPLo (oralis)
VPLc (caudalis)
Afferent of VPLo
deep cerebellar nuclei
Projection of VPLo
Area 4
Afferent of VPLc
Sc
somatosensory nuclei in medulla
Projection of VPLc
Medial lemniscus
pathway for secondary gustatory fibers
Nucleus solitarius –> ipsilateral central tegmental tract –> VPMpc
This structure separates pretectum and medial nucleus of pulvinar
Nucleus limitants
Posterior nuclear groups receives fibers from
STT and Medial leminscal fiber
Afferent of MGB
Inferior colliculus
The only distinct laminar organization of MGB
Ventral
Medial division of MGB terminates to what layer of the cortex
Layer I
Area 41 organization
High tone: medial group
Low tone: lateral and anterior group
2 Nuclear Complex of LGN
Dorsal LGN
Ventral LGN
What nuclear complex is the major relay for visual system
Dorsal LGN
ventral LGN is also known as
Pregeniculate Nucleus
Do not extend to visual system
2 division of 6 layers of dorsal LGN
Layers 1-2 magnocelullar
Layers 3-6 Parvicellular
Crossed fiber of LGN
1,4 and 6
Uncrossed fiber of LGN
2,3 and 5
Macular representation accounts for how many percent of total LGN volume
12%
Horizontal meridian correspond to
Oblique dorsoventral plane
Medial - superior retinal quadrants
Lateral - inferior retinal quadrants
Vertical meridian correspond to
Caudal margin of the nucleus from medial to lateral
Triadic synaptic arrangement of LGN
Dendrites of both LGN
Golgi type 2 interneuron
Glomeruli of LGN
Golgi type Retinal afferents II Corticogeniculate terminals Reticular thalamic Corticofugal fibers
This group of neurons surrounds lateral, superior and anteroinferior aspect of thalamus
Reticular nucleus
Reticular nucleus is closely related to
Zona incerta
Ventral lateral geniculate
NT of afferent reticular connection
Cholinergic
Function of reticular neurons
Integrate and gate activities of thalamic neurons
basal ganglia has dual entry to reticular thalamic nuclei via
SN and GPe
Efferent of Reticular Thalamic Nuclei
Midbrain Reticular Formation
Superior Colliculus
VPAG
This NT occurs in all laminae
GABA
Excitatory NT of corticofugal of reticular nucleus
Glutamate and aspartate
Anterior cingulate mediates this what receptor
AMPA
Anterior limb of IC contains
Anterior thalamic radiation
Prefrontal corticopontine
Genu contains
Corticobulbar and corticoreticular
Posterior lum contains
Corticospinal Frontopontine Superior thalamic corticotectal corticorubral corticoreticular
Superior thalamic radiation is concern with what function
General somatic efferent
Retrolenticular portion of IC subserves what thalamic radiation
Posterior thalamic
Sublenticular portion of IC subserves what thalamic radiation
Inferior thalamic radiation
Synaptic base of
Rods?
Cones
Rods : Spherule
Cones: Pedicle
Amacrine cell only synapse with
Bipolar neurons
These retinal cells serves to modify trnasmission across the synaptic layer
Horizontal and amacrine
This cells conveys signal from inner to outer one
Interplexiform cells