Time Processing in Huntington Disease

AGOSTINO P.V.; GATTO, E.M.; CESARINI M; SANGUINETTI A; ETCHEVERRY J.L.; GOLOMBEK D.A.

Washington DC

Congreso; 67th American Academy of Neurology Annual Meeting; 2015

Objectives: to assess temporal cognition in two different experiments: a peak-interval time production and a reaction time task in patients with HD. Background: Interval timing is defined as duration discrimination within the seconds-to-minutes range. Cortico-striatal circuits, dopaminergic-glutamatergic pathways and basal ganglia are implicated in 'timing processing' mechanisms (TP). Deficits in cognitive timing functions may contribute to disturbances in voluntary movement. Variability in TP have been described in neurodegenerative disorders including small samples of Huntington disease (HD) patients where abnormalities in TP may be critical for the deterioration of movements. Patients and methods: patients with molecular diagnosis of HD and controls matched by age-sex and educational level composed the sample. The study was approved by Institutional Committee. Timing assessment: The time production task was a variant of the human peak-interval task and was performed as previously published. Production of 3, 6 and 12s target intervals occurred in separate blocks. The reaction time task was adapted and validated from Thorne et al., 2005. Briefly, participants were asked to respond as quickly as possible to black circles appearing on a white screen. Statistical analysis: MATLAB program was used for data analysis and ANOVA test was administered when appropriated. Results and Conclusions: Eight HD patients and 8 controls composed the sample, HD mean age: 46.25 ± 13.03 years and 44.13 ± 12.16 years for controls; mean expanded allele 43±1.36 and mean disease duration 7 years (range 1-12 years). A significant decline in timing function was observed in patients vs. controls. Reaction time was 509.04 ± 159.40 msec in HD patients vs. 290.72 ± 49.66 msec in controls (p=0.0024, unpaired t-test). Moreover, significant differences in the time production task were found, with worse performance in HD compared to controls. Our results contribute to support that timing functions are impaired in HD.