Fractality of tics as a quantitative assessment tool for Tourette syndrome.
J R Soc Interface
; 19(187): 20210742, 2022 02.
Article
em En
| MEDLINE
| ID: mdl-35193387
ABSTRACT
Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent-called the fractal dimension Df-from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6-12 months apart in children with tics, using random walk models and directional statistics. We find that Df is correlated with tic severity as measured by the YGTTS total tic score, and that Df is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics.
Palavras-chave
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Síndrome de Tourette
/
Tiques
Tipo de estudo:
Diagnostic_studies
/
Etiology_studies
/
Prognostic_studies
Limite:
Child
/
Humans
Idioma:
En
Revista:
J R Soc Interface
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Estados Unidos