Aphasia in Persian: Implications for cognitive models of lexical processing

Area of Science:

• Neuroscience
• Linguistics
• Psychology

Background:

• Current models of oral reading involve sublexical, lexical, and semantic pathways.
• Studies in Indo-European and Sino-Tibetan languages inform these models through aphasia research.
• Persian orthography presents unique challenges due to variable vowel representation, affecting print-to-sound mapping transparency.

Purpose of the Study:

• To test the hypothesis that Persian oral reading requires a semantic pathway independent of a non-semantic pathway.
• To investigate selective impairments in object naming and oral reading in Persian speakers with aphasia.
• To explore how orthographic transparency influences reading performance in this population.

Main Methods:

• Assessed 21 Persian speakers with aphasia (ages 18-77).
• Administered object naming (200 items) and oral reading tasks (printed object names).
• Included a non-word reading task to assess sublexical reading abilities.

Main Results:

• Oral reading was significantly more preserved than object naming in most participants.
• A moderate positive correlation was found between object naming and oral reading success.
• Word frequency, age of acquisition, and imageability predicted task success, with an interaction with orthographic transparency.
• Opaque words were read less accurately than transparent words.

Conclusions:

• Persian speakers with aphasia exhibit diverse patterns of acquired dyslexia, some resembling phonological, deep, and surface dyslexia seen in other languages.
• Orthographic transparency plays a crucial role in oral reading accuracy in Persian.
• The findings contribute to understanding reading processes and acquired dyslexia in morphosyllabic writing systems.