In this large-scale analysis of the associations between the plasma levels of 1160 proteins and cognitive function, we identify CA14 and CDCP1 as being associated with processing speed, as measured by the DSST, and having potentially causal effects on hippocampal volume and stroke (CA14) and intracranial aneurysm (CDCP1). The gene discussed is CDCP1; the disease is Dilatation of the cerebral artery.