Speech perception and short-term memory deficits in persistent developmental speech disorder.

Area of Science:

• Linguistics
• Neuroscience
• Developmental Psychology

Background:

• Developmental speech disorders in children can co-occur with speech perception and short-term memory deficits.
• It remains unclear if these deficits are transient developmental delays or persistent features of the disorder.

Purpose of the Study:

• To investigate whether speech perception and short-term memory deficits persist into adulthood in individuals with familial developmental speech disorders.
• To determine if these persistent deficits are associated with the ongoing speech disorder in the absence of language impairment.

Main Methods:

• Compared nine adults with persistent familial developmental speech disorder (no language impairment) to 20 controls.
• Assessed speech perception using tasks involving discrimination of acoustic cues (first formant transitions, stop gaps) for word identification.
• Evaluated verbal and nonverbal short-term memory, including rhythm and tonal memory.

Main Results:

• Significant group differences were observed in discriminating fine acoustic cues (first formant transitions) for word identification.
• Adults with speech disorders exhibited significant deficits in nonverbal (rhythm, tonal) and verbal short-term memory.
• No significant differences were found in the utilization of stop gap durations for word identification.

Conclusions:

• Speech perception deficits, particularly with frequency-based cues, persist into adulthood in familial developmental speech disorders.
• Short-term memory impairments (verbal and nonverbal) are also persistent features of this condition.
• These persistent deficits in speech perception and memory may play a crucial role in the long-term persistence of speech disorders without accompanying language impairments.