Wednesday, December 26, 2007

The French Connection III: New Neuron paper by Giraud team

Hi there. Sorry for the brief absence -- I've been a bit 'indisposed' medically, but am now ready for a fun 2008 on Talking Brains. Happy New Year.

As I indicated before, Anne-Lise Giraud and her colleagues (including me) have a new paper in Neuron that illustrates one of the points I've been carrying on about for a while -- multi-time resolution processing and the Asymmetric Sampling in Time (AST) idea.

The paper, Endogenous Cortical Rhythms Determine Cerebral Specialization for Speech Perception and Production (Neuron 56: 1127-1134), describes a study using concurrent EEG and fMRI. The study shows how theta (slower sampling) and gamma (faster sampling) rhythms (as quantified by EEG) are bilaterally but asymmetrically distributed in the auditory cortices. Moreover (cool bonus data), mouth and tongue motor areas showed theta and gamma -- illustrating that the same cortical oscillations are observed on auditory and speech-motor areas. Cool, no?

Anyway, if you have wondered about some of the temporal claims (and specifically AST) that have appeared in Hickok & Poeppel 2000/2004/2007, recent papers that show exciting empirical support are:

• Giraud et al. (2007), Neuron
• Luo & Poeppel (2007), Neuron
• Boemio et al. (2005), Nature Neuroscience

Martin Meyer and his colleagues (Z├╝rich) have also accumulated some interesting evidence regarding these hypotheses. More on the work by that group soon, in a separate posting.

No comments: