Low dimensional temporal organization of spontaneous eye blinks in adults with developmental disabilities and stereotyped movement disorder

Spontaneous eye blink rate as predictor of dopamine-related cognitive function-A review

An extensive body of research suggests the spontaneous eye blink rate (EBR) is a non-invasive indirect marker of central dopamine (DA) function, with higher EBR predicting higher DA function. In the present review we provide a comprehensive overview of this literature. We broadly divide the available research in studies that aim to disentangle the dopaminergic underpinnings of EBR, investigate its utility in diagnosis of DA-related disorders and responsivity to drug treatment, and, lastly, investigate EBR as predictor of individual differences in DA-related cognitive performance. We conclude (i) EBR can reflect both DA receptor subtype D1 and D2 activity, although baseline EBR might be most strongly related to the latter, (ii) EBR can predict hypo- and hyperdopaminergic activity as well as normalization of this activity following treatment, and (iii) EBR can reliably predict individual differences in performance on many cognitive tasks, in particular those related to reward-driven behavior and cognitive flexibility. In sum, this review establishes EBR as a useful predictor of DA in a wide variety of contexts.

Development and temporal organization of repetitive behavior in an animal model

Despite repetitive behaviors being a common feature of a number of clinical disorders and ubiquitous in normative development, little attention has been given to their ontogeny or temporal dynamics. We characterized these features in a mouse model of repetitive behavior to identify discrete trajectories of development and developmental changes in temporal dynamics. Three qualitatively distinct trajectory groups were identified which allowed for an examination of the interaction between temporal organization and developmental trajectory. Significant differences in temporal dynamics were found across development and among trajectory groups. Significant interactions of trajectory group and developmental period on temporal organization were also found. The combination of group-based trajectory modeling and a novel method for analysis and graphic depiction of temporal organization allowed for the exploration of the interplay between these two fundamental behavioral processes. Such methods may be useful tools in the assessment and treatment of repetitive behavior in clinical populations.