Beyond Uniform Impairment: Investigating Declarative Memory Profiles in Nonspecific Mild Intellectual Disability...

Area of Science:

• Neuroscience
• Developmental Psychology
• Cognitive Psychology

Background:

• Individuals with intellectual disabilities (ID) often exhibit memory impairments, but with considerable heterogeneity.
• Nonspecific mild intellectual disability (NSID) presents a unique challenge due to variability in cognitive profiles.
• Understanding declarative memory heterogeneity is crucial for accurate diagnosis and intervention in NSID.

Purpose of the Study:

• To investigate the heterogeneity of declarative memory in children and adolescents with nonspecific mild intellectual disability (NSID).
• To identify distinct declarative memory profiles within the NSID population.
• To determine potential predictors of NSID based on memory performance.

Main Methods:

• Latent profile analysis (LPA) was performed on a large sample (N=999, including 114 with NSID).
• Six supplementary memory indices from the Test of Memory and Learning-Second Edition (TOMAL-2) were utilized.
• Logistic regression analysis assessed the predictive power of TOMAL-2 indices for NSID diagnosis.

Main Results:

• Two distinct memory profiles emerged: a 'memory impaired group' (24%) and a 'high-performers group' (76%).
• Individuals with NSID were significantly more likely to be in the 'memory impaired group'.
• Lower scores in Attention/Concentration, Sequential Memory, and Verbal Delayed Recall predicted NSID; however, 25% of mild NSID individuals were high performers.

Conclusions:

• Declarative memory in NSID is heterogeneous, contradicting assumptions of uniform impairment.
• Identified memory profiles and predictive indices can enhance diagnostic precision and intervention tailoring.
• Further research is needed to explore factors contributing to memory variability and optimize support strategies.