impulsive behavior is common in patients with the chronic tic disorder tourette s syndrome ( ts ) , usually associated with comorbid attention deficit hyperactivity disorder ( adhd ) . about half of patients with ts obsessions are persistent ideas , thoughts , impulses or images that are intrusive and inappropriate and cause anxiety and distress . compulsions are repetitive behaviors or mental acts that are carried out to prevent or reduce anxiety ( hollander 1993 ) . the obsessive compulsive symptoms associated with ts more frequently involve symmetry , ordering , aggression , religion and sex and less often contamination compared to those of primary obsessive compulsive disorder ( george et al 1993 ; holzer et al 1994 ; miguel et al 1997 ; cath et al 2001 ) . in addition to the typical obsessions , compulsions and impulsive behaviors , in caring for a large population of ts patients we have observed a variety of more complex forms that have overlapping clinical phenomenology and have caused diagnostic and therapeutic confusion . some complex motor tics like clapping , touching , rubbing , tapping and knocking can be the identical motor action as a compulsion . the action is generally considered a compulsion if it has certain characteristics : ( 1 ) it is performed according to specific rules ( ie , it is ritualistic ) such as a certain number of times , in a certain order or at a certain time of day ( eg , bedtime rituals ) , ( 2 ) it is performed in response to an obsession , or ( 3 ) it is performed to reduce anxiety , distress or discomfort or to ward off future harm or a dreaded event . unlike compulsions , motor tics are often preceded by focal uncomfortable somatic sensations (  sensory tics  ) that are temporarily relieved by the tics ( kurlan et al 1989 ) . tics generally improve with the use of an alpha - adrenergic agonist or antipsychotic medications while compulsions usually respond to selective serotonin reuptake inhibitors ( ssris ) . for example , some ts patients describe their premonitory sensations as being more generalized , psychic and distressing ( kurlan et al 1996 ) and report that the tics are performed to relieve this discomfort . we have seen many instances in which ts patients have individual repetitive behaviors that include focal and generalized premonitory sensations ,  just right  phenomena and specific rules . thus , there are repetitive behaviors in ts patients that are virtually impossible to classify as a tic or a compulsion and have features of both . while ssri s are an effective pharamacologic treatment for ocd , there is a substantial subgroup of ocd patients who derive no benefit from this treatment ( mcdougle et al 2000 ; miguel et al 2003 ) . some studies suggest that the presence of tics is associated with a poorer treatment response to ssri s and the addition of a neuroleptic drug is an effective treatment strategy ( mcdougle et al 1990 ; mcdougle et al 1994 ; mcdougle et al 1995 ) . in our experience , the patients with fall into this category and optimal therapy involves the combination of anti - obsessional and tic - suppressing treatments . the following case illustrates  compultics  occurring during reading in a young girl . c. presented for evaluation at age 7 years due to motor and vocal tics . she was the product of a normal pregnancy , labor and delivery and had normal developmental milestones . at 4 years of age she developed repetitive eye blinking lasting approximately 6 weeks . at age 6 , eye blinking recurred and was accompanied by facial and sniffing tics . c. reported that when attempting to read she experienced an irresistible urge to always hold 3 additional pages of the book in her right hand and to jerk her eyes up and down the page that she was reading in a multiple of 3 . if she mistakenly jerked her eyes an extra time , she would have to repeat the process . for example , she would only wear the third outfit that she tried on and she had to smell each item of clothing 3 times before trying it on . other obsessive - compulsive symptoms included a bedtime ritual ( ie , both parents had to kiss her 3 times before going to bed ) and the need for symmetry and  evening - up  behavior ( eg , both sides of her body had to  feel  the same , such as the tightness of fit of her shoes ) . she was observed to have eye blinking and other facial tics and sniffing tics , all considered to be mild in severity . modest improvement in her rituals occurred following cognitive behavioral therapy but those associated with reading persisted , causing significant problems in school and with homework . the counting aspect of the reading ritual resolved following treatment with escitalopram 10 mg / day , but eye tics continued to interfere with reading . these resolved after risperidone 0.5 mg / day was added . impulsive behaviors are performed with little forethought and without regards to consequences , driven by the desire to obtain pleasure , gratification or arousal ( hollander et al 2000 ) . this is in contrast to compulsions , which are repetitive behaviors or mental acts that are carried out to prevent or reduce anxiety . patients with ts often experience impulsiveness as part of commonly associated attention deficit hyperactivity disorder ( adhd ) . some complex motor tics like poking , hitting , pushing , touching , coprolalic insults and other socially inappropriate comments and actions ( kurlan 1988 ) are directed at others , and have aggressive and impulsive qualities . some of these tics also have a compulsive quality , such as needing to be done a certain number of times or until the patient feels  just right  . thus , some tics take on both impulsive and compulsive qualities (  impulsive - compulsive tics  ) . optimum therapy may require targeting tics , obsessive - compulsive behavior and impulse control dysfunction . treatments that may improve impulse control problems include antipsychotic medication , mood stabilizing drugs , stimulants and cognitive - behavioral therapy . some impulsive behaviors become repetitive and compulsive ( eg , kleptomania , pathological gambling ) ( table 3 ) . hollander ( 2000 ) considers these to be disorders of impulse control but also part of the obsessive compulsive spectrum , characterized by the inability to inhibit or delay repetitive behaviors ( hollander et al 1995 ) . these disorders can be viewed along a continuum with an over - exaggerated sense of harm at the obsessive - compulsive end and an underestimated sense of harm at the impulsive end ( hollander et al 2000 ) . we find that many young ts patients who experience intermittent explosive disorder ( rage attacks ) ( budman et al 2000 ) have ocd and that the attacks are triggered by interference with a compulsive ritual or by unexpected events that are poorly tolerated in the setting of a rigid , inflexible , perfectionistic obsessive - compulsive thought pattern . the rages are often triggered when a compulsive ritual is interfered with , thus disrupting the completion of the ritual . the patient , fearing something terrible will happen if the compulsion is not completed , responds with rage and anger at that which caused the disruption . however , it often appears to others that there has been no trigger for the rage since the actual trigger is an internal experience of the patient rather than an external , observable stimulus . thus , these explosions can appear to either have no precipitant , or a precipitant that does not warrant the outcome . in this regard the optimal treatment of the rage attacks involves therapy directed at reducing obsessive - compulsiveness , impulsivity and aggression . the case presented here illustrates impulsive - compulsive behavior : j. is an 18 year old male high school graduate , diagnosed with ts , ocd and adhd at age 9 . following diagnosis , j. was treated with a low dose atypical anti - psychotic to diminish tics , an ssri for ocd , and methylphenidate for adhd . while most symptoms were under relatively good control , a few persisted despite medication changes . ocd symptoms also waxed and waned and were primarily focused on germs , cleanliness and fear of contamination . this led to an avoidance of touching things and fear of being touched , especially unexpectedly . obsessive ruminations about germs resulted in the belief that he could be contaminated simply by being touched by someone he did not know . when he entered middle school , this information was conveyed to the school , with a request for special accommodations to help avoid a negative reaction to being touched by other students while switching classrooms between periods ( eg , being allowed to leave classes before the other students ) , but this request was denied . within two weeks of starting school , he was unexpectedly and accidentally pushed from behind by a female student . he then had a rage attack and physically assaulted the girl , resulting in the school calling the police and his subsequent arrest . he was later transferred to a small , private school for children with neurodevelopmental syndromes . since then , he has learned to better control his impulsivity and ocd symptoms have lessened . guanfacine was added to his treatment regimen to help dampen impulsive behavior . since then , no similar incident has recurred . , it may be that certain obsessions such as religious preoccupations and fear of harming self or others are more highly associated with psychotic features ( tolin et al 2001 ) . although the development of schizophrenia in patients with ocd is relatively uncommon ( eisen et al 1999 ) , ocd can result in symptoms that overlap with psychotic phenomena and can be difficult to separate , diagnose and treat ( hwang et al 2000 ) . it is not uncommon for patients with ocd to develop delusions during the course of their illness but they tend to be transient and do not necessarily reflect a schizophrenia - spectrum disorder ( razali 2000 ) . the following case presentation illustrates this symptom type : d. is a 14 year old girl who was referred to the ts clinic for evaluation of vocal and motor tics , obsessive compulsive behavior and attentional disturbance . birth history was unremarkable and she met all developmental milestones normally . however , d. was hyperactive , impulsive and had low frustration tolerance . cut off a boy s penis  . inability to pay attention and concentrate was also observed , but she was able to hyperfocus when reading . at age 7 she was seen by a psychiatrist for an evaluation of adhd and started on methylphenidate ( mph ) . she was taken off mph and started on amphetamine salts , also with good control of her adhd symptoms . , d. decided she no longer wanted to take her medication and was allowed to stop . she was placed on sertraline following evidence of low mood , threats of self - harm and oppositional and defiant behavior , with little impact . suicidal threats were made and the medication dosage was increased . during this time , regressive behaviors ( eg , thumb sucking ) developed . she also developed obsessive - compulsive symptoms including perfectionism , the need for orderliness and symmetry and excessive cleanliness . she became preoccupied with certain topics , such as methods of torture and fairies , and developed invisible friends , to which she gave names and interacted with on a daily basis . these invisible friends persisted ; indeed , she responded to them as if they were real friends . when asked at age 14 if she thought these invisible friends and fairies really exist , she replied  yes  . despite this , she had many actual friends and enjoyed socializing , playing sports , painting , drawing , singing and acting . over the years , she saw several counselors and therapists to help with her behaviors . tourette s girl  and the frequency of her tics increased to up to 30 per minute according to teachers and parents . at this time she was referred to our clinic . d.s examination was significant for low mood and the presence of mild vocal and motor tics , most notably facial tics and eye blinking . the following diagnoses were made : tourette syndrome , adhd - combined type , ocd with delusional features and dysthymia . in her case , the adhd and ocd were considered the most disabling features and targeted for treatment . amphetamine salts were restarted with resultant improvement in adhd symptoms and no significant worsening of tics . in fact , tics lessened over time without having to introduce a tic - suppressing agent . mood stabilized with ongoing use of sertraline and obsessive compulsive symptoms became non - disabling . within a few months , d.s academic performance was again excellent . her imaginary friends  disappeared  and she reportedly  felt sad losing them  . currently , at age 14 , she frequently draws pictures of fairies and continues her belief in their existence . no new psychotic - like features have emerged and she remains stable . while non - psychotic children have been reported to have hallucinations , mainly auditory ( schreier 1999 ; yoshizumi et al 2004 ) , some children with ts have been described as having  intense inner auditory or visual eidetic thought ( which ) may approximate hallucinations yet , the occurrence of psychotic - like obsessive symptoms in patients with ts has received little attention ( sverd et al 1993 ) . our own community epidemiologic study involving about 1600 school children found that 19.2% of children with tics obtained abnormal scores on the  thought disorder index of the achenbach child behavior checklist ( cbcl ) compared to 8.6% of children without tics ( kurlan et al 2002 ) . this index includes symptoms such as suspiciousness , having strange ideas , and hearing things that are nt there ( achenbach 1991 ) . uncharacteristic of ocd and ts , however , are negative symptoms associated with schizophrenia , such as anhedonia , flat affect and avolition . the presence of these symptoms , especially with onset signaling a significant change from baseline personality , may help differentiate a schizophrenic process from ocd and ts . one of the first case descriptions was freud s  rat man  who experienced obsessional fears that something terrible would happen to his father and fianc and had delusions that his parents could read his mind ( freud 1955 ) . it has been reported that certain obsessions , such as fear of harming self or others and religious preoccupations , are more highly associated with psychosis ( tolin et al 2001 ) . in a study of patients with ocd and psychosis , 77% showed significant improvement when treated with a combination of an antipsychotic and an anti - obsessional medication ( ganesan et al 2001 ) . a subgroup of schizophrenia patients have severe and persistent ocd and some clinicians have suggested that they represent a specific subtype of schizophrenia (  schizo - obsessive  or  obsessive compulsive schizophrenia  ) based on a distinct clinical profile ( khullar et al 2001 ) , neuropsychological pattern ( berman et al 1998 ; lysaker et al 2000 ) , course ( hwang et al 2000 ) and treatment response ( reznik et al 2000 ) . it is probably not surprising to see complex obsessive compulsive or impulsive symptoms , sometimes mixed with tics or psychotic features in patients with ts based on shared neuroanatomic sites of dysfunction . disturbances of frontal cortical - basal ganglia and limbic pathways have been implicated in ts , ocd and schizophrenia by a variety of neuroimaging approaches ( eliez et al 2000 ) , neuropsychological studies ( berman et al 1998 ; cavallaro et al 2003 ) and neurophysiological studies ( sweeney et al 1992 ) . additionally , we have seen that virtually any pathological process that disrupts normal basal ganglia development can result in a similar complex clinical syndrome of tics and multiple psychiatric symptoms (  developmental basal ganglia syndrome  ) ( palumbo et al 1997 ) . neurosurgical ( montoya et al 2002 ) and clinical studies ( kurlan et al 1990 ; gray 1994 ; kim et al 2001 ; amo et al 2004 ) have indicated the involvement of limbic structures in ocd and schizophrenia . a dysfunction of neural circuits interconnecting the orbitofrontal cortex , basal ganglia , limbic system and thalamus has been proposed as serving a critical role in the expression of ocd ( modell et al 1989 ) . there is some evidence that the central dopaminergic system is involved in the pathophysiology of ts in which either excess dopamine or a hypersensistivity of d2 receptors is present ( dion et al 2002 ) . combined disturbances of dopamine and serotonin neurotransmission have also been linked to ts , ocd and schizophrenia ( kapur et al 1996 ; sallee et al 1996 ; segawa 2003 ; yang et al 2004 ) and may characterize disorders manifested chiefly by the inability to properly delay or inhibit repetitive thoughts or behaviors ( hollander 1993 ) . ocd symptoms tend to respond well to ssri s , which block serotonin ( 5ht ) reuptake ( zohar et al 2000 ) and traditional neuroleptic dopamine receptor antagonists have been shown to suppress tics ( scahill et al 2003 ) . therefore , atypical antipsychotic medications that target both dopamine and serotonin receptors have efficacy for ts , ocd and schizophrenia ( sallee et al 2003 ; lynch 1997 ; borison et al 1992 ) . unlike traditional neuroleptics which block d2 receptors only , atypical agents block both d2 and 5-ht2 receptors , and have a lower tendency to cause extrapyramidal symptoms ( mandoki 1995 ) , thus making them a particularly useful treatment option for patients with complex tic - compulsive - psychotic features . complex obsessions , compulsions and impulsive behaviors in ts patients are not uncommon and can overlap with other clinical phenomena , such as tics and psychosis , causing diagnostic and therapeutic confusion . recognition of these complex behaviors in ts is critical in optimizing treatment ( see table 2 ) . often , patients with these problems will require combination treatment directed at alleviating tics , ocd , impulsivity and/or psychosis . while the current information is observational , future research aimed at clarifying and quantifying the defining features of these complex symptoms is clearly an important area of study . whether scores on formal rating scales can define and separate these ts subtypes is unknown . quantifying symptom characteristics of tics and other comorbid conditions may also be important to better understand and treat these clinical problems .
obsessive compulsive and impulsive symptoms are prevalent in patients with tourette s syndrome ( ts ) and well recognized as part of the ts spectrum . 
 however , some complex obsessive compulsive and impulsive behaviors may be mistaken for other symptoms , such as complex tics or psychotic behavior . 
 in addition , the overlap between tics , compulsions , and impulsive actions can make them impossible to discern from each other . 
 yet , the proper recognition of these symptoms is critical in optimizing treatment outcome in ts patients . 
 this paper will review complex obsessive compulsive and impulsive behaviors that may occur in patients with ts and discuss implications for diagnosis and treatment .