Sensorimotor area Spt under attack (but they're shooting blanks): Reply to Parker Jones et al. 2014

A recent report in Frontiers (link to it here) by my good friends Oiwi Parker Jones (first author) and Cathy Price (senior author) challenges the claim that area Spt is a sensorimotor integration area for vocal tract actions.  Their attack comes from multiple fronts, both fMRI and lesion data.  On the fMRI side they sought to determine whether Spt was more active during repetition tasks, particularly for pseudowords which demand sensory-to-motor translation, compared to two auditory naming tasks.  One involved listening to animal sounds and naming the animal and the other involved listening to someone humming and naming the gender of the hummer.  These tasks did not involve direct translation between a heard auditory code and a motor code and so shouldn't activate Spt as vigorously as the repetition tasks, they argued.  The lesion data involved 8 patients with auditory repetition deficits were studied and their lesions mapped to identify the anatomical source of the problem.  We have shown previously (Buchsbaum et al. 2011) that area Spt, as mapped using fMRI in 100+ participants, overlaps the lesion distribution of conduction aphasia (N=14).What Parker Jones et al.  found was that "No brain areas, including Spt, were more activated by auditory repetition of pseudowords compared to sound naming."  They further found that the lesions associated with repetition deficits involved the arcuate fasciculus, not necessarily Spt. They conclude, ...
Source: Talking Brains - Category: Neurologists Authors: Source Type: blogs