Lecture 2 internal nerve structures Flashcards
(29 cards)
What is the Fronto-Occipital Fasciculi?
Nerve bundles that carry sensory information from the back of the brain to the Prefrontal Association Area
What are the two portions of the Fronto-Occipital Fasciculi?
- Superior Fronto-Occipital Fasciculus
- Inferior Fronto-Occipital Fasciculus
What structures do the Uncinate Fasciculus connect?
Connects Temporal Limbic structures and the Prefrontal cortex
What is the function of the Inferior Longitudinal Fasciculus?
Connects the occipital and Anterior temporal lobes
- For rapid transfer of visual info to limbic structures (memory)
What is the function of the Superior Longitudinal Fasciculus?
Carries sensory information from the back of the brain to the Motor areas of the frontal lobe and prefrontal cortex
- For attention, descision making, motor tasks
What are the Association Bundles?
Fibers carrying sensory information from the back of the brain to the front
- Used for focusing attention, decision making
(within one hemisphere)
What is the function of the internal capsule?
Transfers sensory and motor information between the cerebral cortex and subcortical structures
What is the Corona Radiata?
“Radiating crown”
- Fanning out of the fibers of the interal capsule
What happens if the internal capsule is damaged?
- Varying degrees of paralysis and/or sensory loss on the contralateral (Opposite) side of the body
What are the three capsules in the Brain?
- Internal Capsule
- External Capsule
- Extreme Capsule
What does the Internal Capsule consist of?
- Descending motor projections (primary motor cortex to spinal cord)
- Ascending sensory projections (Thalamus to primary sensory cortex)
In the anterior limb of the Internal Capsule, what part of the brain are the connections to and from?
- Frontal Lobe
In the Posterior limb of the internal capsule, what does this area contain?
Descending Motor fibers
Ascending Sensory fibers
What are the different projections found in the External Capsule?
- Corticostriate projections (between the Cortex and the Basal Ganglia)
- Projections of Basal Forebrain Cholinergic neurons (diffuse brain system) to the cortex
Which two structures are found on either side of the External Capsule?
- The Lenticular nucleus forms the inner wall of the capsule
- The Claustrum froms the exterior wall of the capsule
What structures make up the lenticular nucleus starting from exterior to interior?
- (exterior portion forming the interior wall to the external capsule) -> Putamen
- (Interior portion forming the exterior wall to the interior capsule) -> Globus Pallidus
What is the Claustrum?
- collection of neurons (nucleus) that has reciprocal connections with the cortex and thalamus
- integrating multiple sensory modalities
What does the Extreme Capsule consist of?
- White matter fibers connecting the claustrum and the insula
- UNKNOWN function
What two structures are found on either side of the Extreme Capsule?
- Claustrum forms the interior wall of the capsule
- The insula forms the exterior wall of the capsule
What is a Commissure?
A bundle of fibers interconnecting the two hemispheres
What structures does the anterior commisure connect and what is its function?
Bridge between the left and right anterior temporal lobes/amygdala
- control behavior, emotions, and motivation
- unifies emotional responses between the two hemispheres
- infront of junction between the Thalamus and Hypothalamus
What is the largest commissure in the brain?
- Corpus Callosum
What is the function of the corpus callosum?
Connects left and right hemisphers of the cortex
- upper surface forms the FLOOR of the longitudinal fissure
What are the portions of the corpus callosum?
- Rostrum (“Beak”) - anterior portion
- Genu (“Knee”) - large anterior protrusion above the beak
- Body - Large dorsal portion
- Splenium (“roll”) - tail posterior portion
