Visual-motor integration in children with Prader-Willi syndrome

Visual-Motor Integration Deficits in 3q29 Deletion Syndrome

3q29 deletion syndrome (3q29del) is associated with neuropsychiatric and neurodevelopmental phenotypes. We previously reported that graphomotor weakness is present in up to 78% of individuals with 3q29del. We have now explored nuances of the graphomotor phenotype and its association with other comorbidities in this population. Participants were recruited from the online 3q29 registry (3q29deletion.org) for two days of deep phenotyping. 32 individuals with 3q29del (62.5% male) were evaluated with the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI) to assess visual-motor integration. Participants were also evaluated with measures of cognitive ability, executive function, adaptive behavior, and school function. Males with 3q29del performed significantly worse than females on the VMI and Motor Coordination subtest. VMI performance was significantly associated with ADHD diagnosis and cognitive ability. Compared to published data from individuals with 22q11.2 deletion syndrome, individuals with 3q29del showed significantly more impairment. The 3q29 deletion is associated with substantial deficits in visual-motor integration, Visual Perception, and Motor Coordination. Our data suggests that 3q29del may qualify as a nonverbal learning disability. Future studies should assess whether individuals with 3q29del would benefit from early interventions, including occupational therapy.

Early psychomotor development and growth hormone therapy in children with Prader-Willi syndrome: a review

Prader-Willi syndrome (PWS) is a rare genetic disorder caused by the loss of imprinted gene expression on the paternal chromosome 15q11-q13. PWS is characterized by varying degrees of early psychomotor developmental deficits, primarily in cognition, language, and motor development. This review summarizes the early mental cognitive development, language development, and motor development in patients with PWS, compares the correlation of genotype with phenotype, and provides an update regarding the effects and concerns related to potential main side effects of treatment with recombinant human growth hormone on early psycho-cognitive and motor function development along with the linear growth and body composition of children with PWS.Conclusion: Early psychomotor development is strongly correlated with the prognosis of patients with PWS; moreover, current studies support that the initiation of interventions at an early age can exert significant beneficial effects on enhancing the cognitive and linguistic development of patients with PWS and allow them to "catch up" with motor development.  What is Known: • Prader-Willi syndrome is a rare genetic disorder characterized by multisystem damage, and children with Prader-Willi syndrome are typically characterized by early developmental delays, specifically in the areas of cognitive and motor development. • Recombinant human growth hormone therapy is the only medical treatment approved for Prader-Willi syndrome. What is New: • Extensive presentation of psycho-cognitive and motor development features and genotype-phenotype correlation in children with Prader-Willi syndrome.  • The effects of growth hormone on early psychomotor development in children with Prader-Willi syndrome were thoroughly reviewed, including their short- and long-term outcomes and any associated adverse effects.

Adult norms for the Corbett Targeted Coin Test

STUDY DESIGN

Clinical measurement INTRODUCTION: Dexterity is important for daily activities. The Corbett Targeted Coin Test (CTCT) measures dexterity with palm-to-finger translation and proprioceptive target placement, but lacks established norms.

PURPOSE OF THE STUDY

To establish norms for the CTCT with healthy adult subjects.

METHODS

The inclusion criteria consisted of participants that were community dwelling, non-institutionalized, able to make a fist with both hands, perform finger-to-palm translation of twenty coins, and be at least 18 years of age. CTCT standardized testing procedures were followed. Quality of performance (QoP) scores were determined by speed in seconds and number of coin drops (each a 5-second penalty). QoP was summarized within each age, gender and hand dominance subgroup using the mean, median, minimum, and maximum. Correlation coefficients were computed for relationships between age and QoP, and between handspan and QoP.

RESULTS

Of the 207 individuals who participated, 131 were females and 76 males with an age range of 18-86 and mean age of 37.16. Individual QoP scores ranged from 13.8 to 105.3 seconds, with median scores ranging from 28.7 to 53.3 seconds. The mean for males was 37.5 seconds for the dominant hand (range 15.7-105.3) and 42.3 seconds (range 17.9.-86.8) for the non-dominant hand. The mean for females was 34.7 seconds for the dominant hand (range 14.8-67.0) and 38.6 seconds (range 13.8.-82.7) for the non-dominant hand. Lower QoP scores indicate a faster and/or more accurate dexterity performance. Females showed better median QoP for most age groups. The best median QoP scores were seen in the 30-39 and 40-49 age ranges.

DISCUSSION

Our study agrees to some extent with other research that reported dexterity decreases with age, and increases with smaller hand spans.

CONCLUSION

Normative data for the CTCT can be a guide for clinicians evaluating and monitoring patient dexterity with palm-to-finger translation and proprioceptive target placement.

Central neurogenetic signatures of the visuomotor integration system

Visuomotor impairments characterize numerous neurological disorders and neurogenetic syndromes, such as autism spectrum disorder (ASD) and Dravet, Fragile X, Prader-Willi, Turner, and Williams syndromes. Despite recent advances in systems neuroscience, the biological basis underlying visuomotor functional impairments associated with these clinical conditions is poorly understood. In this study, we used neuroimaging connectomic approaches to map the visuomotor integration (VMI) system in the human brain and investigated the topology approximation of the VMI network to the Allen Human Brain Atlas, a whole-brain transcriptome-wide atlas of cortical genetic expression. We found the genetic expression of four genes-TBR1, SCN1A, MAGEL2, and CACNB4-to be prominently associated with visuomotor integrators in the human cortex. TBR1 gene transcripts, an ASD gene whose expression is related to neural development of the cortex and the hippocampus, showed a central spatial allocation within the VMI system. Our findings delineate gene expression traits underlying the VMI system in the human cortex, where specific genes, such as TBR1, are likely to play a central role in its neuronal organization, as well as on specific phenotypes of neurogenetic syndromes.

Face processing and exploration of social signals in Prader-Willi syndrome: a genetic signature

BACKGROUND

Faces are critical social cues that must be perfectly processed in order to engage appropriately in everyday social interactions. In Prader-Willi Syndrome (PWS), a rare genetic disorder characterized by cognitive and behavioural difficulties including autism spectrum disorder, the literature referring to face processing is sparse. Given reports of poor social interactions in individuals with PWS, we sought to assess their face and emotion recognition skills during eyetracking recordings.

RESULTS

Compared with controls, patients with PWS performed more poorly on face/emotion recognition. We observed atypical facial exploration by patients with maternal disomy. These patients looked preferentially at the mouth region, whereas patients with a deletion and controls were more attracted to the eye region. During social scenes, the exploration became more atypical as the social content increased.

CONCLUSIONS

Our comprehensive study brings new insights into the face processing of patients with PWS. Atypical facial exploration was only displayed by patients with the maternal disomy subtype, corresponding to their higher rate of autism spectrum disorder. This finding strongly argues in favor of early identification of this genetic subgroup in order to optimize care by implementing tailored interventions for each patient as soon as possible.

Psychopathological disorders in Prader-Willi syndrome

Prader-Willi syndrome is a genetic disorder caused by chromosomal changes in segment 15q11-q13 including cognitive, mental, and behavioral symptoms, as well as a specific physical phenotype. Both the most common psychopathological changes (intellectual disability, obsessions, impulsivity, autism spectrum disorders, self-injuries) and the main psychiatric comorbidities (affective disorders, psychosis, obsessive-compulsive disorder, autism spectrum disorder) are characterized by a great heterogeneity, which warrants the need for better identification of their frequency and clinical signs. In addition to its effects on body compositionand hypotony, growth hormone has been shown to be useful for regulating patient behavior, and psychoactive drugs are also an option. Other alternatives have shown promising results in experimental trials. Adequate understanding of the psychopathology associated to Prader-Willi syndrome would allow for improving clinical approach, symptom identification, detection of comorbidities, and administration of more effective treatments, leading to better clinical outcomes.

Hand strength and dexterity in patients with Prader-Willi syndrome: a pilot intervention study

OBJECTIVE

The study aim was to examine the hand function (hand strength and dexterity) and intervention effects of training in adults with Prader-Willi syndrome (PWS).

METHODS

Six adults with PWS (two females; mean age 26.14 years) underwent hand muscle strength and dexterity training for 3 months (2 hours per week). The following hand function tests were performed pre- and post-intervention: (1) hand grip, lateral pinch, and tip pinch hand strength tests, (2) the Box and Block test (BBT) for gross manual dexterity and (3) the Purdue Pegboard test for finger dexterity.

RESULTS

Before treatment, all subjects showed lower hand grip, lateral pinch, tip pinch strength, and poorer manual/finger dexterity relative to healthy adults. After training, hand function scores improved on many test items, but only the left hand tip pinch and the right hand BBT performance showed significant improvements.

CONCLUSIONS

All subjects showed lower hand strength and poorer manual/finger dexterity compared with healthy adults; this should be considered during physical training programs. Owing to limitations in the intervention intensity and possible subject behavioral deficits, further research is needed to clarify the effects of this intervention on hand function in PWS patients.

Visual-Motor Integration in Children With Mild Intellectual Disability: A Meta-Analysis

Visual-motor integration (VMI) skills, defined as the coordination of fine motor and visual perceptual abilities, are a very good indicator of a child's overall level of functioning. Research has clearly established that children with intellectual disability (ID) have deficits in VMI skills. This article presents a meta-analytic review of 10 research studies involving 652 children with mild ID for which a VMI skills assessment was also available. We measured the standardized mean difference (Hedges' g) between scores on VMI tests of these children with mild ID and either typically developing children's VMI test scores in these studies or normative mean values on VMI tests used by the studies. While mild ID is defined in part by intelligence scores that are two to three standard deviations below those of typically developing children, the standardized mean difference of VMI differences between typically developing children and children with mild ID in this meta-analysis was 1.75 (95% CI [1.11, 2.38]). Thus, the intellectual and adaptive skill deficits of children with mild ID may be greater (perhaps especially due to their abstract and conceptual reasoning deficits) than their relative VMI deficits. We discuss the possible meaning of this relative VMI strength among children with mild ID and suggest that their stronger VMI skills may be a target for intensive academic interventions as a means of attenuating problems in adaptive functioning.

Deficits in voice and multisensory processing in patients with Prader-Willi syndrome

Prader-Willi syndrome (PWS) is a rare neurodevelopmental and genetic disorder that is characterized by various expression of endocrine, cognitive and behavioral problems, among which a true obsession for food and a deficit of satiety that leads to hyperphagia and severe obesity. Neuropsychological studies have reported that PWS display altered social interactions with a specific weakness in interpreting social information and in responding to them, a symptom closed to that observed in autism spectrum disorders (ASD). Based on the hypothesis that atypical multisensory integration such as face and voice interactions would contribute in PWS to social impairment we investigate the abilities of PWS to process communication signals including the human voice. Patients with PWS recruited from the national reference center for PWS performed a simple detection task of stimuli presented in an uni-o or bimodal condition, as well as a voice discrimination task. Compared to control typically developing (TD) individuals, PWS present a specific deficit in discriminating human voices from environmental sounds. Further, PWS present a much lower multisensory benefits with an absence of violation of the race model indicating that multisensory information do not converge and interact prior to the initiation of the behavioral response. All the deficits observed in PWS were stronger for the subgroup of patients suffering from Uniparental Disomy, a population known to be more sensitive to ASD. Altogether, our study suggests that the deficits in social behavior observed in PWS derive at least partly from an impairment in deciphering the social information carried by voice signals, face signals, and the combination of both. In addition, our work is in agreement with the brain imaging studies revealing an alteration in PWS of the "social brain network" including the STS region involved in processing human voices.