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Mitchell Glickstein

Publications and source records attributed to Mitchell Glickstein.

4 recordsLinked to original sources
PubMed2006

Independent roles for the dorsal paraflocculus and vermal lobule VII of the cerebellum in visuomotor coordination.

Two distinct areas of cerebellar cortex, vermal lobule VII and the dorsal paraflocculus (DPFl) receive visual input. To help understand the visuomotor functions of these two regions, we compared their afferent and efferent connections using the tracers wheatgerm agglutinin horseradish peroxidase (WGA-HRP) and biotinilated dextran amine (BDA). The sources of both mossy fibre and climbing fibre input to the two areas are different. The main mossy fibre input to lobule VII is from the nucleus reticularis tegmenti pontis (NRTP), which relays visual information from the superior colliculus, while the main mossy fibre input to the DPFl is from the pontine nuclei, relaying information from cortical visual areas. The DPFl and lobule VII both also receive mossy fibre input from several common brainstem regions, but from different subsets of cells. These include visual input from the dorsolateral pons, and vestibular-oculomotor input from the medial vestibular nucleus (MVe) and the nucleus prepositus hypoglossi (Nph). The climbing fibre input to the two cerebellar regions is from different subdivisions of the inferior olivary nuclei. Climbing fibres from the caudal medial accessory olive (cMAO) project to lobule VII, while the rostral MAO (rMAO) and the principal olive (PO) project to the DPFl. The efferent projections from lobule VII and the DPF1 are to all of the recognised oculomotor and visual areas within the deep cerebellar nuclei, but to separate territories. Both regions play a role in eye movement control. The DPFl may also have a role in visually guided reaching.

Afferent Pathways↗
PubMed2005

Cerebellum lesions and finger use.

We tested monkeys, patients, and normal control human subjects in a task that requires skilled use of the fingers. Animals and patients with lesions of the cerebellum, particularly of the cerebellar hemispheres, were severely impaired in retrieving raisins from small holes (monkeys) or shifting beads from place to place through a series of such holes, using the index finger alone or in apposition (humans). As they descend through the pontine nuclei, pyramidal tract fibres give off a collateral to pontine cells. The axons of pontine cells, in turn, project to the cerebellar cortex, where they terminate as mossy fibres. We suggest that the corollary discharge from pyramidal tract fibres to the cerebellum via the pontine nuclei is required for skilled, co-coordinated, simultaneous or sequential movements.

Adolescent↗
PubMed2003

Subcortical projections of the parietal lobes.

Parietal lobe visual areas project to several subcortical targets. Three of the most prominent of these are to the basal ganglia, superior colliculus, and pontine nuclei. All three are probably involved in some aspect of visually guided movement. One of the largest systems of fiber connections in the human brain arises in the cerebral cortex, and relays to the cerebellum via the pontine nuclei. Pontocerebellar axons terminate within the cerebellar cortex as mossy fibers. Cells in the cerebral cortex that project to the pontine nuclei are all pyramidal in shape, and all are located in lamina V of the cerebral cortex. Subcortical projections from the somatosensory cortex of rats shows that cells that project to the basal ganglia and cerebellum occupy different sublaminae of layer V. Some cortical pyramidal cells' axons may divide, with one branch projecting to the superior colliculus, the other to the pontine nuclei. Temporal lobe visual areas, which are involved in form recognition and learning, do not project to the cerebellum. Reciprocal connections from the cerebellum back to the parietal lobe may play a role in converting visual information from retinotopic to head-centered coordinates.

Animals↗