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In the last few years research has focused on the role of premonitory urges in TS since these urges are generally triggers for tics and are as bothersome as the tics themselves to many people. Premonitory urges have a sensory component and many TS patients also report sensory sensitivities. Researchers have been clarifying the nature of premonitory urges and determining the underlying causes of the sensory sensitivities.  Scores on the Premonitory Urge for Tics Scale (PUTS) and the University of São Paulo Sensory Phenomena Scale Total (USP-SPS)  were significantly correlated with total tic severity, tic complexity and vocal tic scores for TS adults \citep{Kano_2015}. The PUTS and USP-SPS scores were also correlated with scores on the Dimensional Yale-Brown Obsessive-Compulsive Scale. This study provides additional evidence that the association between premonitory urges, as measured by PUTS scores, and tics is complex and may be influenced by obsessive-compulsive tendencies. Another study examined the association between premonitory urges and interoceptive awareness \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 found 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.