Time estimation in schizophrenia: an fMRI study at adjusted levels of difficulty.

fMRI was performed in nine male schizophrenia patients and 15 healthy male controls during an auditory time estimation (timing), a frequency (i.e. pitch) discrimination task, and rest. An adaptive psychophysical approach, the weighted up-down method, was used to adjust individual performance to a level of 75% probability for correct answers. Although performing on the same level of individual difficulty, schizophrenia patients revealed less activations in prefrontal cortex and caudate nucleus, comparing time vs rest. Timing specific differences (i.e. timing vs pitch) between patients and controls were found in the posterior putamen, anterior thalamus, and right medial prefrontal cortex, with patients showing relative hypoactivity. Impairment in time estimation in schizophrenia might be mediated by specific fronto-thalamo-striatal dysfunction.