Color Vision Losses in Autism Spectrum Disorders.

Autism spectrum disorders (ASDs) are neurodevelopmental conditions characterized by impairments in social/communication abilities and restricted behaviors. The present study aims to examine color vision discrimination in ASD children and adolescents without intellectual disability. The participants were also subdivided in order to compare color vision thresholds of autistic participants and those who achieved diagnostic criteria for Asperger Syndrome (AS). Nine subjects with autism, 11 participants with AS and 36 typically developing children and adolescents participated in the study. Color vision was assessed by the Cambridge Color Test (CCT). The Trivector protocol was administered to determine color discrimination thresholds along the protan, deutan, and tritan color confusion lines. Data from ASD participants were compared to tolerance limits for 90% of the population with 90% probability obtained from controls thresholds. Of the 20 ASD individuals examined, 6 (30%) showed color vision losses. Elevated color discrimination thresholds were found in 3/9 participants with autism and in 3/11 AS participants. Diffuse and tritan deficits were found. Mechanisms for chromatic losses may be either at the retinal level and/or reflect reduced cortical integration.

Neurotoxic impact of mercury on the central nervous system evaluated by neuropsychological tests and on the autonomic nervous system evaluated by dynamic pupillometry.

Mercury vapor is highly toxic to the human body. The present study aimed to investigate the occurrence of neuropsychological dysfunction in former workers of fluorescent lamps factories that were exposed to mercury vapor (years after cessation of exposure), diagnosed with chronic mercurialism, and to investigate the effects of such exposure on the Autonomic Nervous System (ANS) using the non-invasive method of dynamic pupillometry. The exposed group and a control group matched by age and educational level were evaluated by the Beck Depression Inventory and with the computerized neuropsychological battery CANTABeclipse - subtests of working memory (Spatial Span), spatial memory (Spatial Recognition Memory), visual memory (Pattern Recognition Memory) and action planning (Stockings of Cambridge). The ANS was assessed by dynamic pupillometry, which provides information on the operation on both the sympathetic and parasympathetic functions. Depression scores were significantly higher among the former workers when compared with the control group. The exposed group also showed significantly worse performance in most of the cognitive functions assessed. In the dynamic pupillometry test, former workers showed significantly lower response than the control group in the sympathetic response parameter (time of 75% of pupillary recovery at 10cd/m2 luminance). Our study found indications that are suggestive of cognitive deficits and losses in sympathetic autonomic activity among patients occupationally exposed to mercury vapor.

Generalization of sensory auditory learning to top-down skills in a randomized controlled trial.

BACKGROUND: Research has shown that auditory training improves auditory sensory skills; however, it is unclear whether this improvement is transferred to top-down skills, such as memory, attention, and language, and whether it depends on group characteristics in regard to memory and attention skills. PURPOSE: The primary goal of this research was to investigate the generalization of learning from auditory sensory skills to top-down skills such as memory, attention, and language. We also aimed to compare whether this generalization process occurs in the same way among typically developing children and children with speech sound disorder. RESEARCH DESIGN: This study was a randomized controlled trial. STUDY SAMPLE: Typically developing 7- to 12-yr-old children and children with speech sound disorder were separated into four groups: a trained control group (TDT; n = 10, age 9.6 ± 2.0 yr), a nontrained control group (TDNT; n = 11, age 8.2 ± 1.6 yr), a trained study group (SSDT; n = 10, age 7.7 ± 1.2 yr), and a nontrained study group (SSDNT; n = 8, age 8.6 ± 1.2 yr). INTERVENTION: Both trained groups underwent a computerized, nonverbal auditory training that focused on frequency discrimination, ordering, and backward-masking tasks. The training consisted of twelve 45 min sessions, once a week, for a total of 9 hr of training, approximately. DATA COLLECTION AND ANALYSIS: Near-transfer (Gap-In-Noise [GIN] and Frequency Pattern Test) and far-transfer measures (auditory and visual sustained attention tests, phonological working memory and language tests) were applied before and after training. The results were analyzed using a 2 × 2 × 2 mixed-model analysis of variance with the group and training as the between-group variables and the period as the within-group variable. The significance threshold was p ≤ 0.05. RESULTS: There was a group × period × training interaction for GIN [F(1.35) = 7.18, p = 0.011], indicating a significant threshold reduction only for the TDT group (Tukey multiple comparisons). There was a significant group × period interaction [F(1.35) = 5.52, p = 0.025] and a training × period interaction for visual reaction time [F(1.35) = 4.20, p = 0.048], indicating improvement in the SSDT group and worsening in both nontrained groups. There was also a significant group × training × period interaction [F(1.35) = 4.27, p = 0.046] for the auditory false alarms, with a significant improvement after training only for the SSDT group. Analysis of variance also revealed that all groups exhibited approximately the same level of gains for all measures, except for GIN [F(3,38) = 4.261, p = 0.011] and visual response time [F(3.38) = 4.069, p = 0.014]. CONCLUSIONS: After training, the TDT group demonstrated a significant improvement for GIN and the SSDT exhibited the same for sustained attention, indicating learning generalization from an auditory sensory training to a top-down skill. For the other measures, all groups exhibited approximately the same level of gains, indicating the presence of a test-retest effect. Our findings also show that the memory span was not related to the learning generalization process given that the SSDT exhibited a more pronounced gain in attention skills after the sensory training.

The use of the Cambridge Neuropsychological Test Automated Battery (CANTAB) in neuropsychological assessment: application in Brazilian research with control children and adults with neurological disorders

Computerized neuropsychological tests can be effective and have many benefits. This paper addresses these issues using the computer-based Cambridge Neuropsychological Test Automated Battery (CANTAB) to assess Brazilian children and adults. Preliminary normative data for Brazilian children obtained in a series of CANTAB subtests are presented together with data from adults (controls) and samples of patients with multiple sclerosis and Duchenne muscular dystrophy. The results obtained in children confirmed the normative values reported for American children (Luciana & Nelson, 2002), indicating high applicability of the CANTAB battery for children in the evaluation of visual memory, working memory, planning, and set shifting. For multiple sclerosis patients, CANTAB revealed differences between the control and multiple sclerosis groups for all subtests employed, including visual memory, working memory, spatial memory, decision making, inhibitory control, and sustained attention. In children with Duchenne muscular dystrophy, the CANTAB tests revealed specific detriments in attention and memory. These results of the application of CANTAB in different patient groups indicate that the battery is appropriate for assessing several central nervous system diseases.

The use of the Cambridge Neuropsychological Test Automated Battery (CANTAB) in neuropsychological assessment: application in Brazilian research with control children and adults with neurological disorders

Computerized neuropsychological tests can be effective and have many benefits. This paper addresses these issues using the computer-based Cambridge Neuropsychological Test Automated Battery (CANTAB) to assess Brazilian children and adults. Preliminary normative data for Brazilian children obtained in a series of CANTAB subtests are presented together with data from adults (controls) and samples of patients with multiple sclerosis and Duchenne muscular dystrophy. The results obtained in children confirmed the normative values reported for American children (Luciana & Nelson, 2002), indicating high applicability of the CANTAB battery for children in the evaluation of visual memory, working memory, planning, and set shifting. For multiple sclerosis patients, CANTAB revealed differences between the control and multiple sclerosis groups for all subtests employed, including visual memory, working memory, spatial memory, decision making, inhibitory control, and sustained attention. In children with Duchenne muscular dystrophy, the CANTAB tests revealed specific detriments in attention and memory. These results of the application of CANTAB in different patient groups indicate that the battery is appropriate for assessing several central nervous system diseases.(AU)