Adaptive behaviour in Down syndrome: a cross-sectional study from childhood to adulthood

Abstract

Acquired equivalence (AE) is a form of feedback-based associative learning where the subject learns that two or more stimuli are equivalent in terms of being mapped onto the same outcomes or responses. While several studies dealt with how various neurological and psychiatric conditions affect performance on AE tasks (typically with small populations), studies dealing with AE in healthy subjects are rare, and no study has ever made an attempt to plot the development of this form of learning from the childhood through adulthood. In a cross-sectional study, we assessed the AE performance of 265 healthy subjects aged 3 to 52 years with the computer-based Rutgers Equivalence Test (Fish-Face Test, FFT). The test assesses three main aspects of AE: the efficiency of pair learning, the efficiency of the retrieval of acquired pairs, and the ability to generalise previous knowledge to a new stimulus that partially overlaps with the previous ones. It has been demonstrated in imaging studies that the initial, pair learning phase of this specific test is dependent on the basal ganglia, while its generalization phase requires the hippocampi. We found that both pair learning and retrieval exhibited development well into adulthood, but generalisation did not, after having reached its adult-like level by the age of 6. We propose that these findings might be explained by the integrative encoding theory that focuses on the parallel dopaminergic mid-brain-striatum/midbrain-hippocampus connections.

Outcome Measures for Clinical Trials in Down Syndrome

“…interpersonal skills), practical (e.g. activities of daily living), communication (e.g., language use), and motor skills (e.g., gross motor, fine-motor) learned and used by people so they can function in everyday living situations, has been widely studied in individuals with IDD and more specifically in individuals with DS (Dressler, Perelli, Feucht, & Bargagna, 2010; Dykens, Hodapp, & Evans, 2006). As a way of measuring strengths and weaknesses in daily functioning, assessing adaptive behavior in people with DS is critical for determining relations with cognitive abilities, quality of life, or level of independence.…”

The Health-Related Quality of Life of Adults with Down Syndrome

“…Extant literature on adaptive behavior of adults with DS reports low adaptive behavior levels for all domains and subdomains (Adams & Oliver, 2010;Di Nuovo & Buono, 2011;Dressler, Perelli, Feucht, & Bargagna, 2010;Witts & Elders, 1998). However, all studies used the Vineland Adaptive Behavior Scales (VABS) which complicates comparison.…”

“…According to Sparrow et al (2005), when the Vineland-II was created, the VABS was considerably modified to increase the age-range, which was birth to 19 years old for the VABS (Sattler, 1992). Dressler et al (2010) reported low adaptive levels for 40 adults with DS over the age of 20 residing in Italy, however they reported age-equivalents rather than v-scale scores and standard scores, which makes direct comparison challenging. Another challenge was that Dressler et al separated the adults with DS into age groups of 20-30 years old and over 30 years old.…”

“…The principle of life-span development is important because adults with DS continue to learn and change throughout adulthood (Dressler, Perelli, Feucht, & Bargagna, 2010;Hewitt, Hinkle, & Miccio, 2005). The principle of life-span development is applicable to the HRQOL of adults with DS through the changing of attitudes and understanding of the effects health problems, health risks, health-care utilization, and adaptive behavior have on the transitions, and thus on the trajectories of adults with DS.…”

“…The VABS has a Cronbach's alpha coefficient of 0.98 for individuals with intellectual disabilities. Dressler, Perelli, Feucht, and Bargagna (2010) used the VABS (adapted Italian Version) to investigate associations between the adaptive behavior, health, and cognitive ability of individuals with DS who resided in Italy and were between the ages of 4 to 52 years. Dressler et al reported that individuals with DS continue to develop adaptive behaviors throughout the life-span.…”