-
This part of the diencephalon is the largest part and consists of 2 ovoid masses connected in the midline
dorsal thalamus
-
The functions of the hypothalamus
- Autonomic Functions-- Sympathetic/Parasympathetic (blood pressure, etc)
- (Endocrine Control; regulation of food and water intake; emotions; circadian rhythms)
-
The diencephalon is composed of 4 major parts. Name them.
- the dorsal thalamus
- hypothalamus
- epithalamus
- ventral thalamus [subthalamus]
-
The dorsal thalamus has connections with
- sensory & motor systems
- also has connections with limbic system
-
The hypothalamus has connections with
forebrain, brainstem, spinal cord
-
The ventral thalamus (subthalamus) has connections with
basal ganglia - motor system
-
The epithalamus has connections with
the limbic system
-
The junction bewtween the diencephalon and the midbrain is a line from the _____________________ to the edge of the ________________________.
- posterior commisure
- mamillary bodies
-
The medial aspect of each thalamus borders the ___________
3rd ventricle
-
Output from the thalamus is mainly to the _____________ and it receives reciprocal input from the cortex
cerebral cortex
-
The two dorsal thalami are connected at the midline by
the interthalamic adhesion
-
The lateral aspect of the thalamus is covered by the _________
The thalamus is divided into 4 parts by the ____________
- External Medullary Lamina
- Internal Medullary Lamina
-
Within the external medullary lamina is the ___________
thalamic reticular nucleus
-
-
The Internal Medullary Lamina divides the Thalamus into 4 parts
- Anterior
- Lateral (dorsal and ventral tiers)
- Medial
- Intralaminar Regions
-
Diencephalon --> Dorsal Thalamus --> Lateral --> Dorsal Tier --> _____________
Pulvinar
-
Diencephalon --> Dorsal Thalamus --> Lateral --> Dorsal Tier --> Pulvinar
Where are the geniculate bodies(medial/lateral) located
Posterior and inferior to the Pulvinar. They are the 2 bumps
-
The Medial and Lateral Geniculate Bodies are sometimes referred to as the
Metathalamus
-
Diencephalon --> Dorsal Thalamus --> Anterior Region
forms a prominent wedge caudal to the __________
interventricular foramina
-
Diencephalon --> Dorsal Thalamus --> Anterior Thalmic Nuclei receives input from _____________ and projects back to __________________ [parts of limbic system]
limbic system structures (mamillary bodies & hippocampus)
cingulate gyrus and hypothalamus
-
Diencephalon --> Dorsal Thalamus --> Medial Thalmic Nuclei consists of __________ and the small ____________ region [adjacent to Internal medullary lamina]
- dorsomedial nucleus
- paralaminar
-
Diencephalon --> Dorsal Thalamus --> Medial Thalamic --> Dorsomedial Nucleus has connections with the ___________ lobes and ______________
temporal and amygdala (emotions and subjective states)
-
Diencephalon --> Dorsal Thalamus --> Medial Thalamic --> Paralaminar Region is involved with _____
eye movements
-
Diencephalon --> Dorsal Thalamus --> Lateral Thalamic subdivided into ________ and _________
Name the subdivisions of those subdivisions! :-)
- Dorsal Tier
- ----LD
- ----LP
- ----Pulvinar
- Venteral Tier
- ----VA
- ----VL
- ----VP
- +++ VPL
- +++VPM
- +++VI
-
Breakdown of Lateral Thalmic Nuclei
Dorsal Tier----LD----LP----Pulvinar
Venteral Tier----VA----VL----VP
+++ VPL+++VPM+++VI
The LD have connections with _____
the cingulate gyrus
-
Breakdown of Lateral Thalmic Nuclei
Dorsal Tier----LD----LP----Pulvinar
Venteral Tier----VA----VL----VP
+++ VPL+++VPM+++VI
The LP have connections with _____
parietal lobe
-
Breakdown of Lateral Thalmic Nuclei
Dorsal Tier----LD----LP----Pulvinar
Venteral Tier----VA----VL----VP
+++ VPL+++VPM+++VI
The Pulvinar has connections with _________
frontal, parietal, and temporal lobes
-
Breakdown of Lateral Thalmic Nuclei
Dorsal Tier----LD----LP----Pulvinar
Venteral Tier----VA----VL----VP
+++ VPL+++VPM+++VI
The Pulvinar is concerned with _________________
- visual funcyions
- and
- eye movements
-
Breakdown of Lateral Thalmic Nuclei
Dorsal Tier----LD----LP----Pulvinar
Venteral Tier----VA----VL----VP
+++ VPL+++VPM+++VI
The Pulvinar receives input from _____ and projects to _____
- superior colliculus
- and
- visual association cortex
-
Dorsal Thalamus --> Anterior, Medial, Lateral, Intralaminar
The geniculate nuclei are in which group
Lateral Thalamic
-
Medial Geniculate receives _____ info and has connections with the _____ lobe.
Lateral Geniculate receives ____ info and has connections with the ____ lobe.
- auditory; temporal ---inferior colliculus to MEDIAL
- visual; occipital -- CALCARINE SULCUS (primary visual cortex)
-
Lateral Thalmic Nuclei : ventral tier consists of
____ & ____ = motor related nuclei, output to FRONTAL LOBE
______ = sensory nucleus
VA & VL
VP
-
VA and VL both get input from ______
VL gets input from ________
-
Lateral Thalmic -- ventral tier VP is subdivided into
- VPL - sensory input from body
- VPM - sensory input from face
- VI -
-
The VPL and VPM project to the ______ lobe
parietal (primary somatosensory cortex) --post central gyrus
-
The INTRALAMINAR NUCLEI (4th part of dorsal thalamus)
are the 2 in the Y called ______ nuclei
and the 1 in the stem of the Y called ____
These nuclei project to _______, _______, and ____.
- parafascicular
- centromedian
basal ganglia, other thalamic nuclei, and the cortex
-
Thes nuclei are "other nuclei" found along the medial edge of the thalamus = ___________
They are involved with regulation of limbic functions
Midline Nuclei
-
This "other nucleus" are within the EXTERNAL MEDULLARY LAMINA and are involved with modulating the responses of the neurons in the thalamus to incoming cortical input "gates the output"
Thalamic Reticular Nucleus
-
SPECIFIC OR NONSPECIFIC NUCELI produce rapidly conducted, localized response, in ipsilateral cortex
SPECIFIC
-
SPECIFIC OR NONSPECIFIC NUCELI produce widespread activity in the cortex of both hemispheres
NONSPECIFIC
-
Explain 2 types of Specific Nuclei and give examples
- Specific
- 1 - Relay --receive input from mainly ONE source, process and send to a localized region
- examples: VPL, VOM,, MGB, LGB, VL, anterior nucleus
- 2 - Association --receive input from different structures and send output to more than one area of cortex
- example: pulvinar, DM, LD, LP
-
What are some examples of non-specific nuclei (those thought to modulate excitability of large areas of cortex)
- intralaminar nuclei
- midline nuclei
- parts of VA
-
Diencephalon breakdown
limbic system ____
hypothalamus
-
Diencephalon breakdown
sensory, motor, limbic sys ______
thalamus (dorsal thalamus)
-
Diencephalon Breakdown
motor ______
ventral (subthalamus)
-
Diencephalon Breakdown
olfactory, visceral, somatic info (limbic) ______
Epithalamus
-
This part of diencephalon has numerous afferent and efferent connections
hypothalamus
-
The Epithalamus is characterized by ______ and _____
- pineal gland - secretes hormones into blood steam, produces melatonin
- habenular nuclei - olfactory, visceral, and somatic info integrated
-
What is the main blood supply to the diencephalon
- Circle of Willis with perforating branches from
- ACA & Ant Communicating
- PCA & Post Communicating
-
Thalmic Nuclei are small so that lesions producing highly specific effects are ____
not common!
-
contralateral hemianesthesia
- loss of sensations such as:
- discriminative touch
- 2 point discrimination
- vibration
- conscious proprioception
-
Lesions -
If damage includes VPL/VPM, what happens
If damage includes VA/VL, what happens
If damage to geniculate body, what happens
- contralateral hemian-esthesia
- movement disorders (ataxia, intention tremor)
- contralateral homonymous hemian-opsia (visual probs)
-
What is hyperalgesia --due to VPL/VPM lesion
sometimes after a period of recover
|
|