Figure 6.

Time series of brain response. Analysis of group-averaged relative neuronal response (estimated by deconvolution of fMRI time series with the hemodynamic response function) differentiated brain response to increasing nausea from potential confounds such as (A) the motor response underlying the button press event. (B) Increasing phasic response with increasing nausea was seen in the amygdala, where phasic activity preceded the rating change to strong nausea by 6–9 s (red arrow). (C) Increasing sustained response was manifest in anterior insula by persistent brain activation following rating change to strong nausea (red arrow). n.b. M1 = primary motor cortex, aIns = anterior insula, amyg = amygdala.