Preschool MRI predictors of tic outcomes from a 15-year longitudinal study

PROJECT SUMMARY / ABSTRACT
Tic disorders including Tourette syndrome (TS) are very common, and often impair quality of life.
Many TS patients find symptoms improve over adolescence, but others do not. Very little
information is available to inform individual prognosis in TS, and existing studies cannot dissociate
behavioral or brain features preceding tics from those that may be caused by prolonged ticcing.
A unique data set allows us now to examine these questions prospectively in a large sample of
children not selected for the presence or absence of tics. Over 300 children participating in the
Preschool Depression Study (PDS), half with and half without some depressive symptoms in
preschool, had clinical assessments and behavioral tasks over a 15-year period, along with 5 waves of
MRI of the brain. Video recordings were made during and between various tasks at each of 8 visits
covering ages 3-19. Our preliminary data (expert review of video from 52 participants) shows that we
can detect tics from these recordings, and we calculate that almost half of the children in the PDS will
show tics at some visit in this study.
We will examine the video from each study visit to identify the presence and severity of any tics. We
will also invite all the study participants, now young adults age 21-25,
to complete a study visit to
diagnose any current or past tics
. We will use these data to identify clinical features prior to the onset of
tics in children who show tics on video at later visits (Aim 1a). Such a pre-tic follow-up study has
never been performed, and may identify novel tic-related clinical / behavioral features that, because
they precede tics, cannot be caused by ticcing. In children with tics, we will also identify clinical or
MRI features when children first manifest tics that predict outcome at later visits; we will validate these
results in extant data from two independent longitudinal studies of tics (Aim 1b). The results of
Aim 1 may prove clinically useful for prognosis, and may provide valuable new insights into
etiology, pathophysiology, and potentially secondary prevention of tic disorders.
A second aim will identify clinical and brain imaging factors that may relate to tic pathophysiology,
either (within subjects) by comparing changes over time in these factors as tic severity changes over
time, or (between groups) by comparing children with vs. those without tics, controlling for age.
This project will leverage existing data funded by NIMH, along with new identification of tics on
video from 2,000 study visits, in order to clarify pathophysiology and work towards scientifically-
based novel treatments. The investigators are experienced in TS research and child psychopathology,
and are ideally suited to bring this study to a successful conclusion.

Grant Number: 3R01MH127187-02S1
NIH Institute/Center: NIH
Principal Investigator: KEVIN BLACK