Forebrain Anatomy & Limbic System Flashcards
What are the four parts of the diencephalon?
epithalamus (pineal gland & habenula)
thalamus
hypothalamus
subthalamus
The epithalamus contains the ___ gland and the ___.
pineal; habenula
Pineal gland secretes ___, is released during ___, and regulates ___-___ cycles.
melatonin; darkness; sleep-wake
What is a paired structure located near the base of the pineal gland?
habenula
What is the major input to the epithalamus?
stria meduallris (limbic input)
What is the major output to the epithalamus?
habenulointerpeduncular tract (fasciculus retroflexus) to the midbrain RF
T/F. All the sensory pathways including smell relay to the thalamus.
False, all sensory except olfaction.
What are the subdivisions of the thalamic nuclei?
anterior medial lateral intralaminar reticular midline
What are the two tiers of the lateral division?
dorsal and ventral
What structure divides the thalamus?
the internal medullary lamina
The ___ subdivision is the largest and the anterior subdivision sits in a split in the ___ ___ ___.
lateral; internal medullary lamina
What type of neuron synapses on the projection neurons and regulates its firing?
interneurons
___ inputs convey info to the thalamic nucleus and pass them on nearly directly to the cortex.
Specific
___ inputs arise in the cortex and thalamic reticular nucleus and enter the thalamus to regulate how the thalamus sends its information to the cortex.
Regulatory
What receive well defined specific input from the subcortical source and project to a well-defined area of cortex?
Relay nuclei
T/F. Association nuclei receive specific input from an association cortex and project back.
True
___ nuclei receive a distinct set of specific inputs (basal ganglia not the cortex) and they project out to cortex and basal ganglia.
intralaminar
T/F. The reticular nucleus is involved in regulatory input and although they receive input from the cortex and thalamus they do not send projections to the cortex. They send inhibitory axons to the thalamus
True.
The ___ nucleus is a sheet of neurons and axons must transverse it to enter/leave the thalamus and send collateral to it.
reticular
What are the main association nuclei?
DM and Pulvinar
The internal capsule collects and forms the ___ ___ down which corticopontine, corticobulbar and corticospinal fibers descend.
cerebral peduncle
How many parts does the internal capsule have?
five
Which limb separates the lenticular nucleus from the thalamus?
posterior
Which limb of the internal capsule separates the lenticular nucleus from the caudate?
anterior limb
