Fine motor skills and unsystematic spatial binding in the common region test (CRT): under-inclusivity in ASD and over-inclusivity in ADHD

Introduction: The Common Region Test (CRT) is useful for predicting children’s visual memory as individual object-place binding predicted better object memory while objects-region coding predicted better place memory. Aim: The aim was to test children with ASD and ADHD with regards to spatial binding in the CRT. Methods: (1) 19 children with autism spectrum disorder (ASD), (2) 20 children with attention-deficit hyperactivity disorder (ADHD), (3) gender-matched chronological age (CA) and (4) verbal mental age (MA) typically developing (TD) children as control groups were tested with the CRT and Bender Gestalt tests (N = 117). Results: Children with ASD and ADHD showed more unsystematic coding than TD children. This was due to lower fine motor skills, and in children with ADHD also because of reduced verbal naming. Almost all children with ASD presented the less mature under-inclusive Type I unsystematic coding which included object-place binding, while children with ADHD showed the overinclusive Type II unsystematic coding that was overriding the Gestalt-like properties of proximity and similarity. Conclusions: It was demonstrated that the CRT is a useful screening instrument for ASD and ADHD that shows that their spatial categorization varies in their unsystematic visuo-spatial classification due to fine motor skill deficiencies

Exploring spatial memory in children with autism and ADHD

The study investigates spatial memory in neurotypicals, ASD and ADHD children. In a reaction-time accuracy task, children (N = 117) were presented with a grid containing twenty-five individual places. In the presentation phase, children saw different categories of object-in-places which varied from technical to social role play toys. An interference object which was either the same or a different-object exemplar filled the delay between the presentation and test. At test, children were required to recall the location occupied by the object. Among the clinical and matched control groups tested, comparatively better place memory accuracy was evident in ASD children; however this was accompanied by longer place memory reaction times. Same-object presentation in the delay was improving place memory accuracy and speeding up reaction times of children, in comparison to a different-object exemplar. Technical objects were better remembered by the mainly male sample than roleplay and neutral objects, but this particular category of objects had the slowest reaction times. When the binding strategies as per Common Region Test (CRT) were included in the analyses, place memory accuracy was more accurate among systematic coders than unsystematic coders. Interestingly, place memory accuracy and reaction times of those who adopted systematic binding benefitted more from repetition (same-object delay) than those who coded unsystematically - a pattern found across most object categories. Thus, one could say that the repetition was helping to reinforce the object-place binding among systematic coders

Deterioration and Recovery in Verbal Recall: Repetition Helps against Pro-Active Interference

The current study tests whether memory deterioration due to pro-active interference (PI) in verbal recall could be halted via block repetition potentially leading to an increased memory consolidation. We also tested whether bilinguals would be better shielded against memory deterioration than monolinguals because they constantly need to enrich their vocabulary to compensate for their smaller lexica in either language. We tested monolinguals and balanced bilinguals with an N-Back and a free verbal recall task. Repetition showed a significant main effect with a large effect size. In Study 1 (N=45), monolingual men showed less improvement in the repetition blocks, while bilingual men showed a significant doubling of their word recall on each repetition. In Study 2 (N=78), monolingual women were less likely to use the repetition opportunity to improve the word score. Thus, in both studies, a significant monolingual disadvantage showed. When the two data sets were merged (N=123), statistical effects showed that the single word list repetition had successfully and significantly increased resistance to PI, but all individual differences due to bilingualism and sex had disappeared. This supported a previous meta-analysis showing that a monolingual disadvantage does not hold in large samples with N > 100 (Paap effect)