Understanding human brain function requires knowledge of its connectivity: how one structure causally influences other components of the network. A wide range of neurological and psychiatric disorders prominently involve dysfunction of connectivity, including neurodegenerative diseases, autism, and mood disorders. Yet current methods provide only indirect measures of connectivity, and none can directly test how one brain structure causally influences another at the level of the whole brain. A unique opportunity to obtain such measures in the human brain comes from using experimental manipulation of activation through direct electrical stimulation, coupled with the whole-brain field-of-view of fMRI (es-fMRI). Our group has obtained IRB approval, and obtained strong initial data of concurrent es-fMRI in a series of 20 neurosurgical patients over the past two years. Here we intend to leverage this unique approach to the application of important open research questions in emotion, and to dissemination of protocols to a wider community of possible performance sites through this U01 mechanism. Three Aims progress through initial validation and quantification of the approach, mapping of brain networks involved in emotion processing (with a focus on the amygdala and medial prefrontal cortex), and convergent measures with ECoG and rs-fMRI. These Aims offer a mix of immediate implementation based on strong pilot data, more exploratory implementation during the grant, strong validation components, and future planning. The research focus of all Aims is on how emotion is caused by activity in brain networks. This is the topic with the strongest link to readily accessible brain structures for electrical stimulation in neurosurgical epilepsy patients (amygdala and prefrontal cortex). The work would have immediate implications for deep brain stimulation to treat diseases like depression, and long-term implications for eventually mapping out the effective functional connectome of the human brain. We will aim to provide the research community with short, feasible protocols that could be adopted by many other sites in a concerted effort to map effective connectivity in the human brain, eventually accumulating a database for understanding how individual differences in emotion, in health and disease, arise from differences in network connectivity.