Two studies using event-related potentials ERPs) combined with emotional versions of 2-back tasks were performed to examine the effects of negative context on working memory (WM) updating task performance among anxiously attached individuals. One study also assessed the soothing effect of priming memories of attachment security on task performance. Three types of information, including negative attachment pictures, general negative pictures and neutral pictures, were used as materials in the present study. Impairment in WM updating capacity was found in the context of negative attachment pictures in both studies, and the ERP results revealed the following dynamic process: the participants showed enhanced attention to negative attachment stimuli during the initial encoding stage, as expressed by a larger P1, but undue immersion in negative emotion led to a reduced P300 during the elaborate stage. However, security priming was useful in reducing mood disturbance in the context of a WM updating task, and the participants performed better on the task after secure attachment activation. The implications of these findings for emotional WM updating capacity and information processing patterns among anxiously attached individuals are discussed.