Nerve
Cerebellar peduncles
Input and output bundles linking cerebellum and brainstem
High-yield
Middle is the largest and mainly carries pontocerebellar input. Inferior is mixed but predominantly afferent. Superior is predominantly efferent, with important exceptions such as anterior spinocerebellar input.
Overview
The cerebellum exchanges information through three pairs of peduncles. The middle pair brings signals from pontine nuclei, the inferior pair carries several sensory inputs and some outputs, and the superior pair conveys much of the deep nuclei’s output toward the midbrain and thalamus.
Reference facts
- Origin
- Superior: chiefly deep cerebellar nuclei; middle: opposite pontine nuclei; inferior: spinal, olivary and vestibular sources plus cerebellar efferents
- Course
- Superior bundles connect toward the midbrain, middle bundles enter at the pons, and inferior bundles connect with the medulla; superior and inferior peduncles border the fourth ventricular region
- Motor
- Superior peduncles carry major output toward the opposite red nucleus and thalamus; inferior connections include fastigial output to vestibular and reticular regions
- Sensory
- Middle peduncles relay cortical information through pontine nuclei; inferior peduncles carry posterior spinocerebellar, cuneocerebellar, olivocerebellar and vestibular input
Clinical correlation
Crossings differ between these pathways. Cerebellar hemisphere injury usually causes limb incoordination on the same side, while the side of signs after a peduncular lesion depends on whether the affected fibers have crossed.
Frequently asked questions
Where do the cerebellar peduncles arise?
Superior: chiefly deep cerebellar nuclei; middle: opposite pontine nuclei; inferior: spinal, olivary and vestibular sources plus cerebellar efferents.
What muscles do the cerebellar peduncles supply?
Superior peduncles carry major output toward the opposite red nucleus and thalamus; inferior connections include fastigial output to vestibular and reticular regions.
What is the sensory distribution of the cerebellar peduncles?
Middle peduncles relay cortical information through pontine nuclei; inferior peduncles carry posterior spinocerebellar, cuneocerebellar, olivocerebellar and vestibular input.
What is the course of the cerebellar peduncles?
Superior bundles connect toward the midbrain, middle bundles enter at the pons, and inferior bundles connect with the medulla; superior and inferior peduncles border the fourth ventricular region.