The primary aims of this study are to investigate the behavioral effects of applying targeted transcranial magnetic stimulation (TMS) to a node of the brain network subserving attention in schizophrenia and schizoaffective disorder and to correlate these effects to changes in brain network connectivity. Assumptions: -Cerebral activity can be investigated through the correlated activity of cortical nodes that constitute functional brain networks -Behavior can be correlated to the strength of correlated activity between and within nodes of these cortical networks -TMS to targeted nodes leads to changes in patterns of activity in these cortical networks Hypothesis: TMS to a node of the attention network in schizophrenia or schizoaffective disorder will influence network connectivity leading to measurable and predictable effects on attention.