The anatomical basis of articulatory and phonological processes: A VLSM study in a cohort of aphasic patients

Introduction: Phonological impairment and articulatory programming impairment may co-occur in aphasic patients and previous research does not offer a clear-cut picture of their anatomical counterparts. Methods: In this study we aimed at disentangling the neuroanatomical foundation of the phonological and articulatory component in a large cohort of aphasic patients. We analyzed speech sampling at the Aachen Aphasia Test (AAT) and we employed voxel-based lesion-symptom mapping (VLSM) to correlate the behavioral performance with the underlying neuroanatomical basis. Results: Predominant phonological impairment is associated with lesions localized in the areas assigned to the phonological network (dorsal superior temporal gyrus, mid-to-posterior superior temporal gyrus). Predominant articulatory impairment is underpinned by damage at the posterior inferior frontal gyrus, premotor cortex and anterior insula. Discussion: In general, our results are in line with Hickok and Poeppel’s (2004; 2008) model of phonological processing and also support a peculiar role played by the anterior insula in articulatory planning (Dronkers & Ogar, 2004). References: Hickok, G. et al. Nature (2007) 8:393-402; Hickok, G., et al. Cognition (2004) 92: 67-99; Dronkers, N. et al. Brain(2004)127:1461-1462.