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Total tic severity and vocal tic scores were significantly correlated with scores on the Premonitory Urge for Tics Scale (PUTS) and the University of São Paulo Sensory Phenomena Scale for TS adults \citep{Kano_2015}. The PUTS scores and the USP-SPS scores were correlated with the scores on the Dimensional Yale-Brown Obsessive-Compulsive Scale. In addition, PUTS scores and USP-SPS total scores were both significantly correlated with tic complexity and YGTSS vocal tic scores.  Another study examined the association between premonitory urges and interoceptive awareness \citep{25879819}.Interoceptive \citep{25879819}. Interoceptive  awareness was measured by how well subjects could count their heartbeats during a specific period of time. Interoceptive awareness, tic severity, and severity of obsessive-compulsive symptoms were used in a multiple regression to predict PUTS scores. Interoceptive awareness was a highly significant predictor of premonitory urges with greater interoceptive awareness being associated with higher PUTS scores. Higher PUTS scores were also associated with greater tic severity but to a lesser extent than interoceptive awareness. The authors suggest that high interoceptive awareness might result in people setting a low threshold for perception of their own internal physiological sensations and therefore interpreting these sensations as an urge to tic. This study, however, also showed that TS subjects generally had lower interoceptive awareness than controls and this result was interpreted as possibly related to downregulation of interoception, perhaps reflecting a compensatory process that developed over time. However, the authors also point out that the reduced interoceptive awareness could reflect the effect of the comorbidities associated with TS. ### Symptoms and comorbidity