Learning efficacy of explicit visuomotor sequences in children with attention-deficit/hyperactivity disorder and Asperger syndrome

Developmental disorders such as attention-deficit/hyperactivity disorder (ADHD) and Asperger syndrome (AS) are often associated with learning disabilities. This study investigated the explicit learning of visuomotor sequences in 17 ADHD children (mean age 12.1), 21 AS children (mean age 12.7), and 15 typically developing children (mean age: 12.3). The participants were required to explore a hidden sequence of button presses by trial and error and elaborate the learned sequence (2 × 10 task: Hikosaka et al. 1996). The results indicated that although ADHD and AS children had a tendency of repeating the same errors and took longer to complete a sequence, both showed a degree and pattern of improvement in accuracy and speed similar to that of typically developing children. These results suggest that the explicit learning of visuomotor sequence in ADHD and AS patients is largely unimpaired

Thermal Perceptual Thresholds are typical in Autism Spectrum Disorder but Strongly Related to Intra-individual Response Variability

Individuals with autism spectrum disorder (ASD) are often reported to exhibit an apparent indifference to pain or temperature. Leading models suggest that this behavior is the result of elevated perceptual thresholds for thermal stimuli, but data to support these assertions are inconclusive. An alternative proposal suggests that the sensory features of ASD arise from increased intra-individual perceptual variability. In this study, we measured method-of-limits warm and cool detection thresholds in 142 individuals (83 with ASD, 59 with typical development [TD], aged 7–54 years), testing relationships with diagnostic group, demographics, and clinical measures. We also investigated the relationship between detection thresholds and a novel measure of intra-individual (trial-to-trial) threshold variability, a putative index of “perceptual noise.” This investigation found no differences in thermal detection thresholds between individuals with ASD and typical controls, despite large differences between groups in sensory reactivity questionnaires and modest group differences in intra-individual variability. Lower performance IQ, male sex, and higher intra-individual variability in threshold estimates were the most significant predictors of elevated detection thresholds. Although no psychophysical measure was significantly correlated with questionnaire measures of sensory hyporeactivity, large intra-individual variability may partially explain the elevated psychophysical thresholds seen in a subset of the ASD population

Executive dysfunction screening and intelectual coefficient measurement in children with attention deficit hyperactivity disorder Tamizaje de la disfunción ejecutiva y medición del coeficiente intelectual en niños con trastorno por déficit de atención-hiperactividad

OBJECTIVE: To perform a complete Intelligence quotient (IQ) measurement (verbal, performance, and total) and subsequently, to compare executive function (EF) measurements in subgroups of children with attention deficit-hyperactivity disorder (ADHD) with a control group. METHOD: We studied a group of children from 7-12 years of age from public elementary schools. Children were selected by means of Diagnostic and Statistical Manual of Mental Disorders-IV-Revised (DSM-IV-R) parent and teacher questionnaires for ADHD. EFs were screened by Weschler Intelligence Scale for Children (WISC-R) performance intelligence quotient (IQ) determination of the following sub-tests: picture completion; block designs, and object assembly tests. Simultaneously, total (T-), performance (P-), and verbal (V-) IQs were measured for each patient. RESULTS: We studied 26 control subjects, and 35 children with ADHD. Numbers of children in each ADHD sub-type group were as follows: 15 in the combined group (-C), 13 in the inattentive group (-I), and 7 in hyperactivity group (-H). We found significant lower EF scores in picture arrangement (F=3.76, df 3,57, p=0.01), block design (F=4.55, df 3,57, p<0.01), and object assembly (F=4.52, df 3,57, p<0.01). Post-hoc analysis showed that differences were located among ADHD-C, ADHD-I, and ADHD-H groups when compared with controls. We found significantly lower cognitive scores in the ADHD-I group as follows: P-IQ (F=3.57, df 3,57, p=0.02), and T-IQ (F=2.90, df 3,57, p=0.04). CONCLUSION: Our results showed that screening of EF alteration in children with ADHD is easy and rapid by means of certain P-IQ determination sub-scales of the WISC test; moreover, complementary IQ determination can be measured simultaneously. Overall, children with ADHD exhibited an EF alteration. ADHD-I children demonstrated lower P-IQ, and T-IQ scores than control children.<br>OBJETIVO: Realizar una medición global de cociente intelectual (CI) (verbal, ejecutivo y total) y comparar las funciones ejecutivas (FE) en los subgrupos de niños con trastorno por déficit de atención-hiperactividad (TDAH) con un grupo control. MÉTODO: Se estudiaron niños de 7-12 años, provenientes de escuelas oficiales primarias. Se les aplicó el cuestionario de criterios diagnósticos de TDAH del DSM-IV-R para padres y maestros. Las FE se tamizaron mediante las sub-escalas de: ordenación de dibujos, diseño con cubos y composición de objetos del WISC-R. En forma paralela se midieron los CI Verbal (-V), Ejecutivo (-E), Total (-T) de cada paciente. RESULTADOS: Se estudiaron 26 niños control y 35 con TDAH. La distribución de niños con TDAH en los diferentes subtipos clínicos fue la siguiente: 15 niños con TDAH combinado (-C), 13 con inatención (-I) y 7 con hiperactividad-impulsividad (-H). Se encontraron calificaciones menores en las sub-escalas de: ordenación de dibujos (F=3,76, gl 3,57, p=0,01), diseño con cubos (F=4,55, gl 3,57, p<0,01) y en la composición de objetos (F=4,52, gl 3,57, p<0,01). El análisis post-hoc mostró que las diferencias se produjeron entre los grupos de TDAH-I, TDAH-H y TDAH-C en relación al de control. Encontramos calificaciones menores en el CI del grupo de TDAH-I en la siguiente forma: CI-E (F=3,57, gl 3,57, p=0,02) y CI-T (F=2,90, gl 3,57 p=0,04). CONCLUSIÓN: Nuestros resultados muestran que las alteraciones de las FE pueden ser fácilmente tamizadas por WISC-R, además de medir simultáneamente el CI. Se encontró que los niños con TDAH de los 3 tipos muestran una disfunción de las FE. También se encontró que los niños con TDAH-I muestran menores puntajes del CI-E y CI-T que los controles