Spatial sequence memory and spatial error monitoring in the Groton Maze Learning Task (GMLT): A validation study of GMLT sub-measures in healthy children

Obstacle negotiation while dual-tasking in children with Developmental Coordination Disorder (DCD): An augmented-reality approach

BACKGROUND

Children with Developmental Coordination Disorder (DCD) exhibit deficits in predictive motor control, balance, and aspects of cognitive control, which are important for safely negotiating obstacles while walking. As concurrent performance of cognitive and motor tasks (dual-tasking) may exacerbate these deficits, we examined motor and cognitive dual-tasking differences between children with DCD and their typically developing (TD) peers during obstacle negotiation.

METHODS

34 children aged 6-12 years (16 TD, 18 DCD) walked along a 12 m path, stepping over an obstacle (30 % or 50 % of leg length) at its mid-point. On dual-task trials, participants completed a simple or complex (cognitive) visual discrimination task presented via an augmented reality headset. Proportional dual-task costs (pDTCs) were measured on cognitive and gait outcomes over three phases: pre-obstacle, obstacle step-over, and post-obstacle.

RESULTS

During the obstacle step-over phase, both groups increased their leading leg clearance when dual-tasking, while the DCD group had larger pDTC than TD for the high obstacle under simple stimulus conditions (viz simple-high combination). The complex cognitive task produced larger pDTCs than the simple one on leading leg clearance and post-obstacle gait variability.

CONCLUSIONS

In general, both DCD and TD groups showed similar pDTCs under complex conditions, while the specific deficit in DCD under the simple-high combination suggests a (default) compensatory strategy during step-over when attention is diverted to a secondary task. Competing cognitive and motor demands during obstacle negotiation present a potential safety risk for children.

Locomotor-cognitive dual-tasking in children with developmental coordination disorder

Introduction

Children with Developmental Coordination Disorder (DCD) demonstrate deficits in predictive motor control and aspects of cognitive control compared with their typically developing (TD) peers. Adjustment to dynamic environments depends on both aspects of control and the deficits for children with DCD may constrain their ability to perform daily actions that involve dual-tasking. Under the assumption that motor-cognitive integration is compromised in children with DCD, we examined proportional dual-task costs using a novel locomotor-cognitive dual-task paradigm that enlisted augmented reality. We expect proportional dual-task performance costs to be greater for children with DCD compared to their TD peers.

Methods

Participants were 34 children aged 6-12 years (16 TD, 18 DCD) who walked along a straight 12 m path under single- and dual-task conditions, the cognitive task being visual discrimination under simple or complex stimulus conditions presented via augmented reality. Dual-task performance was measured in two ways: first, proportional dual-task costs (pDTC) were computed for cognitive and gait outcomes and, second, within-trial costs (p-WTC) were measured as the difference on gait outcomes between pre- and post-stimulus presentation.

Results

On measures of pDTC, TD children increased their double-limb support time when walking in response to a dual-task, while the children with DCD increased their locomotor velocity. On p-WTC, both groups increased their gait variability (step length and step width) when walking in response to a dual-task, of which the TD group had a larger proportional change than the DCD group. Greater pDTCs on motor rather than cognitive outcomes were consistent across groups and method of dual-task performance measurement.

Discussion

Contrary to predictions, our results failed to support dramatic differences in locomotor-cognitive dual-task performance between children with DCD and TD, with both groups tending to priorities the cognitive over the motor task. Inclusion of a within-trial calculation of dual-task interference revealed an expectancy effect for both groups in relation to an impending visual stimulus. It is recommended that dual-task paradigms in the future continue to use augmented reality to present the cognitive task and consider motor tasks of sufficient complexity to probe the limits of performance in children with DCD.

Psilocybin intoxication did not affect daytime or sleep-related declarative memory consolidation in a small sample exploratory analysis

Psilocybin is investigated as a fast-acting antidepressant used in conjunction with psychotherapy. Intact cognitive functions, including memory, are one of the basic conditions of effective psychedelic-assisted therapy. While cognitive and memory processing is attenuated on various domains during psilocybin intoxication, the effect of psilocybin on the consolidation of memories learned outside of acute intoxication is not known. Thus the main aim of the current study was to test the effects of psilocybin on (A) memory consolidation of previously learned material just after the psilocybin session and (B) on overnight memory consolidation the night just after the psilocybin session. 20 healthy volunteers (10 M/10F) were enrolled in a placebo-controlled, double-blind, cross-over design. Effects on declarative memory consolidation in condition (A) The Groton Maze Learning Task and Rey Auditory Verbal Learning Test were used, and for (B) the Pair Associative Learning Test was used. We did not find psilocybin to improve memory consolidation. At the same time, we did not find psilocybin to negatively affect memory consolidation in any of the tests used. This evidence adds to the safety profile for the use of psilocybin.

Development of complex executive function over childhood: Longitudinal growth curve modeling of performance on the Groton Maze Learning Task

This longitudinal study modeled children's complex executive function (EF) development using the Groton Maze Learning Task (GMLT). Using a cohort-sequential design, 147 children (61 males, 5.5-11 years) were recruited from six multicultural primary schools in Melbourne and Perth, Australia. Race/ethnicity data were not available. Children were assessed on the GMLT at 6-month intervals over 2-years between 2010 and 2012. Growth curve models describe age-related change from 5.5 to 12.5 years old. Results showed a quadratic growth trajectory on each measure of error-that is, those that reflect visuospatial memory, executive control (or the ability to apply rules for action), and complex EF. The ability to apply rules for action, while a rate-limiting factor in complex EF, develops rapidly over early-to-mid childhood.

Path Learning in Individuals With Down Syndrome: The Challenge of Learning Condition and Cognitive Abilities

Analyzing navigational abilities and related aspects in individuals with Down syndrome (DS) is of considerable interest because of its relevance to everyday life. This study investigates path learning, the conditions favoring it, and the cognitive abilities involved. A group of 30 adults with DS and 32 typically-developing (TD) children matched on receptive vocabulary were shown a 4 × 4 Floor Matrix and asked to repeat increasingly long sequences of steps by walking on the grid. The sequences were presented under two learning conditions, one called Oral instructions (participants received verbal instructions such as “turn right” or “turn left”), the other Observation (participants watched the experimenter's moves). Participants were also assessed on verbal and visuospatial cognitive measures. The results showed a similarly better performance in both groups when the Floor Matrix task was administered in the Observation as opposed to the Oral instructions condition. As for the relation with cognitive abilities, in the Floor Matrix task in the Oral instructions condition, individuals with DS showed an effect of both verbal and visuospatial abilities, which was only positive for verbal ability. The effect of verbal and visuospatial abilities was negligible in the TD group. In the Observation condition, performance was predicted by sequential working memory in both groups. Overall, these results shed light on path learning in individuals with DS, showing that they benefited from the Observation condition, and that the involvement of their cognitive abilities depended on the learning condition.

Assessing Neuropsychological Functions in Middle Childhood: a Narrative Review of Measures and Their Psychometric Properties Across Context

Background

There is a significant number of neuropsychological measures for use among children aged 6–12 years. However, most of these tests have been developed in high-income contexts (HICs). To avoid or to at least to minimize bias in assessment, most researchers carry out cultural adaptations of these tools. In selecting sub-tests to adapt before using the entire test battery, researchers would benefit from having a reference source summarizing available tools and how easily they can be used in different context. This is where the paper makes a contribution. This narrative review has a twofold aim: first, to identify tools commonly used among 6–12-year-olds; second, to summarize the psychometric properties of these tools especially emphasizing their usage across different cultural contexts.

Methods

We searched the literature from 1 January 1987 to 31 December 2017 for tools used among children aged 6 to 12 years. An extensive search of PubMed, Psych Info and Web of Science using the keywords (i) neuropsychological or neurocognitive with (ii) assessment or test was done.

Results

A hundred and forty-five papers out of 306 reported on psychometric properties of different tools including Behavior Rating Inventory of Executive Functioning—BRIEF (count = 6), Visual-Motor Integration—VMI (count = 6), the Test of Memory Malingering—TOMM (count = 6), MSVT (count = 6) and Continuous Performance Tests—CPT (count = 6). Forty-six percent of the papers reported studies conducted in the USA. Most of these studies were based in high-income countries, which further highlights the need to validate these measures for use in lower- and middle-income countries. Psychometric check was adequate in most tests for measuring executive functioning such as BRIEF, although tests such as CPT that measure complex attention had mixed findings. Moreover, we found that these studies addressed certain aspects of validity and or reliability while leaving out others; thus, a comprehensive picture is lacking.

Conclusion

We propose further studies to thoroughly investigate and report the psychometric properties of these measures, especially in lower- and middle-income countries.

Cognitive and motor function in developmental coordination disorder

AIM

To analyse the development of motor skill and executive function in school-aged children with and without developmental coordination disorder (DCD).

METHOD

Using a longitudinal design, 186 children (86 males, 100 females) aged 6 to 11 years at Time 1 were tested over a 2-year period, 52 of whom were diagnosed with DCD at Time 1 (27 males, 25 females; mean age 8y 5mo, SD 1y 6mo) using DSM-5 criteria. The McCarron Assessment of Neuromuscular Development assessed motor status at Time 1 and at 2-year follow-up (Time 2). Executive function was assessed using a well-validated measure, the Groton Maze Learning Test.

RESULTS

The DCD cohort at Time 1 had moderate incidence of executive function deficit (41%). Most importantly, at a group level, children with persisting DCD (across Times 1 and 2) also showed significantly lower levels of executive function than children with typical motor development at both time points. At an individual level, around 26% of children in this group had persisting executive function deficits relative to normal ranges of performance.

INTERPRETATION

Children with persisting DCD are at significant risk of executive function issues. The combination of motor and cognitive issues as a potential risk factor in the longer-term development of children is discussed.

WHAT THIS PAPER ADDS

Around half of children initially diagnosed with developmental coordination disorder (DCD) had the same diagnosis at 2-year follow-up. 41% of children with DCD have impaired executive function. Children with persisting DCD show poorer executive function than those with typical motor development or remitting DCD.

Path Learning in Individuals With Down Syndrome: The Floor Matrix Task and the Role of Individual Visuo-Spatial Measures

Environment learning is essential in everyday life. In individuals with Down syndrome (DS), this skill has begun to be examined using virtual exploration. Previous studies showed that individuals with DS can learn and remember paths in terms of sequences of turns and straight stretches, albeit with some difficulty, and this learning is supported by their cognitive abilities. This study further investigates environment learning in the DS population, newly examining their ability to learn a path from actual movements, and to learn increasingly long paths, and how their performance relates to their visuo-spatial abilities and everyday spatial activities. A group of 30 individuals with DS and 30 typically-developing (TD) children matched for receptive vocabulary performed a 4 × 4 Floor Matrix task in a grid comprising 16 squares (total area 2.3 × 2.3 meters). The task involved repeating increasingly long sequences of steps by actually moving in the grid. The sequences were presented in two learning conditions, called Observation (when participants watched the experimenter’s moves), or Map (when they were shown a map reproducing the path). Several visuo-spatial measures were also administered. The results showed a clear difference between the two groups’ performance in the individual visuo-spatial measures. In the Floor Matrix task, after controlling for visuo-spatial reasoning ability, both groups benefited to the same degree from the Observation condition vis-à-vis the Map condition, and no group differences emerged. In the group with DS, visuo-spatial abilities were more predictive of performance in the Floor Matrix task in the Observation condition than in the Map condition. The same was true of the TD group, but this difference was much less clear-cut. The visuo-spatial working memory and visualization tasks were the strongest predictors of Floor Matrix task performance. Finally, the group with DS showed a significant relation between Floor Matrix task performance in the Observation condition and everyday spatial activity. These results enlarge on what we know about path learning in individuals with DS and its relation to their visuo-spatial abilities. These findings are discussed within the frame of spatial cognition and the atypical development domain.

Mental rotation ability and everyday-life spatial activities in individuals with Down syndrome

Although certain visuospatial abilities, such as mental rotation, are crucially important in everyday activities, they have been little explored in individuals with Down syndrome (DS). This study investigates: i) mental rotation ability in individuals with DS; and ii) its relation to cognitive abilities and to everyday spatial activities. Forty-eight individuals with DS and 48 typically-developing (TD) children, matched on measures of vocabulary and fluid intelligence, were compared on their performance in a rotation task that involved detecting which of two figures would fit into a hole if rotated (five angles of rotation were considered: 0°, 45°, 90°, 135°, 180°). Participants were also assessed on their visuospatial and verbal cognitive abilities, and on their parents and/or educators reports regarding their everyday spatial activities. Results showed that: (i) individuals with DS were less accurate in mental rotation than TD children, with larger differences between the groups for smaller angles of rotation; individuals with DS could not mentally rotate through 180°, while TD children could; (ii) mental rotation ability was related to fluid intelligence and to spatial activities (though other cognitive abilities are also involved in the latter) to a similar degree in the DS group and the matched TD children. These results are discussed with regard to the atypical development domain and spatial cognition models.