Dissociation of duration-based and beat-based auditory timing in cerebellar degeneration

Abstract

This work tests the hypothesis that the cerebellum is critical to the perception of the timing of sensory events. Auditory tasks were used to assess two types of timing in a group of patients with a stereotyped specific degeneration of the cerebellum: the analysis of single time intervals requiring absolute measurements of time, and the holistic analysis of rhythmic patterns based on relative measures of time using an underlying regular beat. The data support a specific role for the cerebellum only in the absolute timing of single subsecond intervals but not in the relative timing of rhythmic sequences with a regular beat. The findings support the existence of a stopwatch-like cerebellar timing mechanism for absolute intervals that is distinct from mechanisms for entrainment with a regular beat.T he relevance of the human cerebellum to the perception of time intervals and rhythmic sequences is controversial. Involvement of the cerebellum in perceptual timing (the perception of the timing of sensory events), in addition to its role in motor timing (the timed execution of movements), has been suggested by a number of studies (1-6). One distinction that we wish to address here, which has not been made clear in previous work, is between the absolute, duration-based timing of single subsecond intervals and the relative timing of subsecond intervals based on a regular beat. Functional imaging studies suggest neural activity in the human cerebellum during the perception of the absolute duration of single time intervals (7,8) as well as rhythmic patterns with a regular beat (9-13). However, previous lesion work to assess an obligatory cerebellar role in the perception of single time intervals has not yielded consistent results (4,(14)(15)(16)(17). Previous lesion work to assess any obligatory role of the cerebellum in the analysis of rhythmic sequences has assessed only deficits in related motor activity, such as tapping out a beat (4,14,18), that do not allow clear inference about perception.In this study, we test whether the cerebellum is a critical substrate for perceptual tasks that require the absolute, durationbased analysis of single time intervals as well as those that require the relative analysis of time intervals within rhythmic patterns based on a regular beat. Perceptual tests were conducted in the auditory domain, where accurate temporal encoding of sensory events is essential and entrainment with a beat is induced naturally. Tasks were administered to a group of 34 patients with a stereotyped cerebellar degeneration and a matched control group of 40 healthy individuals. Two absolute timing tasks tested the perception of single intervals for a variable and a fixed reference duration, respectively ( Fig. 1 A and B). Three relative timing tasks tested the beat-based analysis of rhythmic sequences, including the detection of the presence of a roughly regular beat (19), a deviation from an isochronous beat (20) and a distortion of a rhythmic pattern with a metrical beat (21) (Fig. 1 C-E). The data support a ce...

Finding the beat: a neural perspective across humans and non-human primates

“…The cerebellum also responds more during learning of non-metric than metric rhythms [40]. The fMRI findings are supported by findings from other methods: deficits in encoding of single durations, but not of metric sequences, occur when cerebellar function is disrupted, either by disease [41] or through transcranial magnetic stimulation [42]. Thus, although the cerebellum is commonly activated during rhythm tasks, the evidence indicates it is involved in absolute, not relative, timing and therefore does not play a significant role in beat perception or entrainment.…”

β Oscillations Are Linked to the Initiation of Sensory-Cued Movement Sequences and the Internal Guidance of Regular Tapping in the Monkey

“…Therefore, our results strongly support the notion that the mCBGT circuit is part of the beat-based timing mechanism, with a global entrainment in the ␤ band during the production of internally timed movements. On the other hand, the cerebellum takes part in absolute timing (Grahn and Rowe, 2009;Grube et al, 2010;Teki et al, 2011) or in the processing of temporal prediction errors, which can occur during the RTT (Teki et al, 2012). However, the mCBGT circuit and the cerebellum are not isolated systems.…”

Sensorimotor synchronization: A review of recent research (2006–2012)

“…However, some recent studies have investigated the timing of successive intervals and yielded results suggesting that different neural substrates are engaged, depending on whether or not an underlying beat is perceived (Grube, Cooper, Chinnery, & Griffiths, 2010;Teki, Grube, Kumar, & Griffiths, 2011). A duration-based mechanism is thought to be responsible for timing successive intervals in the absence of a beat, and it recruits an olivo-cerebellar network.…”