This study demonstrates clear functional differences of simple index finger tapping in early-stage TS. We suggest that this reflects the requirement for additional brain networks to keep a normal performance level during the actual task and adaptive mechanisms due to continuous tic suppression and performance in TS.

AIM This study addressed whether Tourette syndrome is associated with an impairment of fine motor skills or altered interhemispheric transfer. We additionally investigated the association between interhemispheric transfer and size of the corpus callosum.METHOD The sample, a subsample of our larger neuroimaging sample, included 27 treatmentnaive males with 'pure' Tourette syndrome (age range 10y 2mo-14y 4mo; mean age 11y 10mo, SD 1y 2mo) and 26 matched healthy comparison children (age range 10y 2mo-14y 4mo; mean age 11y 10mo, SD 1y 1mo). A finger tapping task and the Purdue Pegboard were used to assess fine motor skills. Interhemispheric transfer time (ITT) was measured with the Poffenberger paradigm. The neuroanatomical data were derived from our previous neuroimaging study.RESULTS ITT was negatively correlated with the size of callosal subregion 3 (r=)0.366, p=0.028), indicating that a shorter ITT was associated with a larger corpus callosum.INTERPRETATION Our findings support the assumption that previously reported impairment of motor skills in Tourette syndrome does not directly result from tics but from other factors such as medication or comorbidities. Following the assumption that callosal subregion 3 in Tourette syndrome grows as a consequence of tic performance over years, our preliminary results suggest that this growth might accelerate interhemispheric transfer in Tourette syndrome.

The differential diagnosis of 46,XY disorders of sex development (DSD) is based on the distinction between forms of gonadal dysgenesis and disorders of androgen biosynthesis and action. However, clinical and endocrine evaluations are often not conclusive. Here, we describe an adolescent female with hirsutism and hyperandrogenization at puberty. Her karyotype was 46,XY, and clinical investigation demonstrated clitoromegaly, but no uterine remnants were detected. Histology of the gonads revealed a testicular structure with a Sertoli-cell-only pattern. Endocrine evaluation showed hypergonadotropic hypogonadism, and the Sertoli cell markers inhibin B and anti-Müllerian hormone were also low. Several molecular genetic studies were initiated. While analyses of the androgen receptor gene, the SRD5A2 gene and HSD17B3 gene were uninformative, a novel p.L230R mutation was found in the NR5A1 gene. A mutant construct proved a severe dysfunction of this variant in functional analysis after recreation and transfection into HeLa cells. We conclude that the NR5A1 p.L230R mutation most likely leads to a spatial and time-dependent Leydig cell and Sertoli cell dysfunction during development not causing the classical gonadal dysgenesis phenotype. This case demonstrates that the current classification should be updated to encompass the overlapping phenotypes of some genetic conditions within 46,XY DSD.

BackgroundCortico-subcortical circuits are organized into the sensorimotor, associative, and limbic loop. These neuronal preconditions play an important role regarding the understanding and treatment of behavioral problems in children. Differencing evidence argues for a lateralized organization of the sensorimotor loop and a bilateral (i.e., non-lateralized) organization of the associative loop. However, a firm behavioral–neurobiological distinction of these circuits has been difficult, specifically in children.ObjectivesThus, the aim was a comprehensive functional visualization and differentiation of the sensorimotor and the associative circuit during childhood. As a new approach, laterality and rostrality features were used to distinguish between the two circuits within one single motor task.MethodsTwenty-four healthy boys performed self-paced index finger tapping with each hand separately during functional magnetic resonance imaging at 3 Tesla.ResultsA contrast analysis for left against right hand movement revealed lateralized activation in typical sensorimotor regions such as primary sensorimotor cortex, caudal supplementary motor area (SMA), caudal putamen, and thalamus. A conjunction analysis confirmed bilateral involvement of known associative regions including pre-SMA, rostral SMA, and rostral putamen.ConclusionA functional visualization of two distinct corticostriatal circuits is provided in childhood. Both the sensorimotor and associative circuit may be discriminated by their laterality characteristics already in minors. Additionally, the results support the concept of a modified functional subdivision of the SMA in a rostral (associative) and caudal (motor) part. A further development of this approach might help to nurture behavioral assessment and neurofeedback training in child mental health.

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