Verbal and memory skills in males with Duchenne muscular dystrophy

Area of Science:

• Neuroscience
• Genetics
• Pediatrics

Background:

• Duchenne muscular dystrophy (DMD) is a progressive pediatric disorder affecting muscle and brain function.
• Children with DMD typically exhibit lower Verbal IQ scores compared to Performance IQ scores.
• Previous research indicates a general cognitive deficit in individuals with DMD.

Purpose of the Study:

• To investigate specific verbal skills and verbal memory in males with Duchenne muscular dystrophy.
• To compare the performance of males with DMD to normative data, unaffected siblings, and children with cerebral palsy (CP).
• To identify specific language and memory deficits associated with DMD.

Main Methods:

• Fifty males with DMD (age 6-14 years) were assessed using the Clinical Evaluation of Language Fundamentals, 3rd edition, and the California Verbal Learning Test for Children.
• Subsets of DMD participants were compared with unaffected siblings (n=24) and males with cerebral palsy (n=23).
• Performance was evaluated against normative values and control groups.

Main Results:

• Males with DMD performed comparably to control groups on most language and verbal memory measures.
• Consistent deficits were observed specifically in tasks requiring immediate verbal repetition (e.g., Recalling Sentences, Concepts and Directions).
• No declarative memory deficits were found; verbal recall abilities were generally well-preserved.

Conclusions:

• Duchenne muscular dystrophy is selectively associated with reduced verbal span capacity, not global language or memory impairment.
• The findings highlight a specific vulnerability in immediate verbal processing in males with DMD.
• DMD's impact on cognitive function appears specific to certain verbal processing aspects, particularly short-term auditory memory.