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Neurology aNd Special SeNSeS ` neurology—AnAtomy And Physiology Neurology aNd Special SeNSeS ` neurology—AnAtomy And Physiology SecTioN iii 499
Limbic system Collection of neural structures involved in The famous 5 F’s.
emotion, long-term memory, olfaction,
A
behavior modulation, ANS function.
Consists of hippocampus (red arrows
in A ), amygdalae, mammillary bodies, anterior
thalamic nuclei, cingulate gyrus (yellow arrows
in A ), entorhinal cortex. Responsible for
Feeding, Fleeing, Fighting, Feeling, and Sex.
Dopaminergic Commonly altered by drugs (eg, antipsychotics) and movement disorders (eg, Parkinson disease).
pathways
PAthWAy symPtoms oF Altered ACtiVity notes
Mesocortical activity “negative” symptoms (eg, anergia, Antipsychotic drugs have limited effect
apathy, lack of spontaneity)
Mesolimbic activity “positive” symptoms (eg, delusions, 1° therapeutic target of antipsychotic drugs
hallucinations) positive symptoms (eg, in schizophrenia)
Nigrostriatal activity extrapyramidal symptoms Major dopaminergic pathway in brain
(eg, dystonia, akathisia, parkinsonism, tardive Significantly affected by movement disorders
dyskinesia) and antipsychotic drugs
Tuberoinfundibular activity prolactin libido, sexual
dysfunction, galactorrhea, gynecomastia (in
men)
Cerebellum Modulates movement; aids in coordination and Lateral lesions—affect voluntary movement of
balance A . extremities (lateral structures); when injured,
A
Input: propensity to fall toward injured (ipsilateral)
Contralateral cortex via middle cerebellar side.
peduncle Medial lesions (eg, vermis, fastigial nuclei,
Ipsilateral proprioceptive information via flocculonodular lobe)—truncal ataxia (wide-
inferior cerebellar peduncle from spinal cord based cerebellar gait), nystagmus, head tilting.
Output: Generally result in bilateral motor deficits
The only output of cerebellar cortex = affecting axial and proximal limb musculature
Purkinje cells (always inhibitory) deep (medial structures).
nuclei of cerebellum contralateral cortex
via superior cerebellar peduncle
Deep nuclei (lateral medial)—Dentate,
Emboliform, Globose, Fastigial Don’t Eat Greasy Foods
FAS1_2019_12-Neurol.indd 499 11/8/19 7:39 AM
