Dolan, R. J., Fletcher, P., Frith, C. D., Friston, K. J., Frackowiak, R. S., & Grasby, P. M. (1995). Dopaminergic modulation of impaired cognitive activation in the anterior cingulate cortex in schizophrenia. Nature, 378, 180-182. doi:10.1038/378180a0.