RESEARCH: The cerebellum: it's about time!

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J Child Neurol 2002 Jan;17(1):1-9 Books, LinkOut

The cerebellum: it's about time! But timing is not

everything--new insights into the role of the

cerebellum in timing motor and cognitive tasks.

Salman MS.

Division of Neurology, Hospital for Sick Children,

Toronto, ON. .Salman@...

Converging evidence from different research studies

supports a role for the cerebellum in timing neural

processes. The cerebellum is part of a distributed

system for motor control. The timing hypothesis

provides a specific functional role for the unique

contribution of the cerebellum. The timing

capabilities of the cerebellum appear to extend beyond

motor control into tasks focusing on perceptual

processing that require the precise representation of

temporal information and sensorimotor learning.

Behavioral and modeling studies suggest that the

cerebellar timing system is best characterized as

providing a near-infinite set of interval-type timers

rather than as a single clock with pacemaker or

oscillatory properties, but this is controversial. In

addition to learning precisely timed motor responses,

the cerebellum is involved in on-line processing using

feed-forward systems for which sensory input is used

prior to movement execution to improve movement

accuracy. This would be a mechanism for triggering

accurate " time. " The cerebellum continues to fascinate

scientists, and although survival is possible without

the cerebellum, the resultant quality of life is

significantly compromised with clumsiness, ataxia,

hypotonia, dysarthria, slowing of various cognitive

perceptual processes, and impaired fine motor and

ocular-motor coordination. The last three decades have

seen the development of research that has focused on

how the cerebellum functions. Further neurophysiologic

research in cerebellar cortical neurotransmission is

likely to further our understanding of the cerebellar

contribution to timing sensorimotor processes.

PMID: 11913561 [PubMed - in process]

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