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Baby videos provide a clue \citep{26246137} | 34 children in Italy were identified as having autistic behaviors in their second year of life. Families reported that development during the first year of life had been normal and they donated the videos that had been recorded before the age of 6 months. Videos of 18 boys were examined in detail. Abnormal general movements, which are spontaneously generated central pattern generators and modulated by more rostral brain regions, were seen 10 of the 11 boys who were eventually diagnosed with autism spectrum disorder between the ages of 3 and 7 years. In contrast, normal general movements were seen in the 8 boys who had autistic features. Interestingly, 7 of the 8 boys with transient autistic behaviors were later diagnosed with Tourette syndrome and 4 of the boys with autism spectrum disorder were diagnosed with TS as a comorbidity. These results, combined with the recent nearly ubiquitous availability of home baby videos in some cultures, suggest a pseudo-prospective study design to identify features predicting later development of TS.  The issue of how comorbidities affect a variety of measures was seen in a study of TS children and adolescents (Guller et al., 2015). Compared to age-matched controls the TS group did significantly worse on the parent-rated Social Responsiveness Scale which measures social impairment. They also significantly longer to complete forms of the Trail Making Tests. However, of the 31 TS subjects, 11 had OCD, 18 had ADHD and 9 had an anxiety disorder. Once these co-occurring conditions were taken into account the group differences on the Trail Making Tests and the Social Responsiveness Scale were no longer significant.  Many factors affect tic frequency. The role of attention on tic frequency was examined under several conditions (/citep{25185800}. In the first study mean tic frequencies were significantly higher for 12 TS subjects compared to baselines when they were alone in a room. Then they were recorded while looking at themselves in a mirror. A second study was performed to determine whether the increase in frequency was due to increased attention to the tics themselves or just due to increased self-awareness. In addition to the conditions from the first study the 16 subjects were also shown videos of themselves while they were not ticcing. Tic frequency was again lower during the baseline compared to the mirror condition. Tic frequency was lower when subjects were watching the video of themselves while not ticcing. The authors suggest that future treatments stressing attention to states when patients experience fewer tics. | – |