Neurocognitive profiles in Salla disease

Area of Science:

• Neuroscience
• Genetics
• Pediatrics

Background:

• Salla disease is a rare Finnish heritage disorder characterized by free sialic acid storage.
• It presents with significant clinical variability, including conventional and severe subtypes.
• Learning disability is a primary manifestation, necessitating detailed neurocognitive profiling.

Purpose of the Study:

• To delineate the detailed neurocognitive profiles of 41 Finnish patients diagnosed with Salla disease.
• To identify characteristic cognitive and motor patterns associated with Salla disease across different age groups.
• To understand the progression of cognitive and motor deficits over time.

Main Methods:

• Psychological and neuropsychological testing was administered to assess neurocognitive development.
• Paediatric neurological examinations were conducted for all participants.
• Speech therapy evaluations were performed to assess communication skills.

Main Results:

• Patients exhibited a distinct cognitive profile: lower non-verbal (mean developmental age 13mo) compared to linguistic skills (mean developmental age 17mo).
• Key impairments included spatial-visual-constructive abilities, tactile/visual form discrimination, and motor skills.
• Receptive language and non-verbal communication were relatively strong, contrasting with expressive speech difficulties.

Conclusions:

• Salla disease presents a characteristic neurocognitive profile despite significant clinical variation.
• Severe motor disability is a common feature, with skills declining more rapidly after the second decade.
• Understanding these profiles aids in managing Salla disease and related learning disabilities.