Abstract

Patient To examine neural responses to aurally-presented sentences, a sparse imaging technique was used to minimize interference from scanner noise. The patient was played a single sentence (or noise-equivalent) in the 7.4s silent period before a single 1.6s scan with stimulus timing jittered relative to scan onset. There were 118 spoken sentences trials, 59 signal correlated noise trials, and an additional 60 silent trials for the purpose of monitoring data quality. The signal correlated noise stimuli had the same duration, spectral profile and amplitude envelope as the original speech, but were entirely unintelligible (S1). The experiment was divided into three sessions of 79 trials with events pseudo-randomly ordered within each scanning session. The sentences were presented using a MRI compatible auditory stimulusdelivery system (Resonance Technology, Northridge, CA), with insert earplugs to further attenuate scanner noise. DMDX software running on a Windows XP PC was used to present the stimulus items.