The left dorsal striatum is involved in the processing of neutral feedback.

In experimental settings, feedback is mostly used to inform about the correctness of a participant's response. Such feedback, however, also provides the information that a response was registered, which is highly significant in any dialog situation. The present functional MRI study investigated the involvement of brain areas in the processing of neutral, verbal feedback.

Sound level dependence of auditory evoked potentials: simultaneous EEG recording and low-noise fMRI.

The simultaneous recording of EEG and fMRI offers the advantage of combining precise spatial information about neuronal processing obtained by fMRI data with the high temporal resolution of EEG data. One problem for the analysis of auditory processing, however, is the noisy environment during fMRI measurements, especially when EPI sequences are employed. While EEG studies outside an MRI scanner repeatedly demonstrated a clear sound level-dependent increase of N1 amplitude, this finding was less obvious in simultaneous recordings inside a scanner.

Contralateral white noise selectively changes left human auditory cortex activity in a lexical decision task.

In a previous study, we hypothesized that the approach of presenting information-bearing stimuli to one ear and noise to the other ear may be a general strategy to determine hemispheric specialization in auditory cortex (AC). In that study, we confirmed the dominant role of the right AC in directional categorization of frequency modulations by showing that fMRI activation of right but not left AC was sharply emphasized when masking noise was presented to the contralateral ear. Here, we tested this hypothesis using a lexical decision task supposed to be mainly processed in the left hemisphere.

Contralateral White Noise Selectively Changes Right Human Auditory Cortex Activity Caused by a FM-Direction Task.

Animal and human studies suggest that directional categorization of frequency-modulated (FM) tones (rising vs. falling) is a function of the right auditory cortex (AC). To investigate this hemispheric specialization in more detail, we analyzed both the binaural and monaural representation of FM tones and the influence of contralateral white noise on the processing of FM tone direction.