Invoking one or more previously dormant functions of an automated assistant in response to detecting, based on processing of vision data from one or more vision components: (1) a particular gesture (e.g., of one or more “invocation gestures”) of a user; and/or (2) detecting that a gaze of the user is directed at an assistant device that provides an automated assistant interface (graphical and/or audible) of the automated assistant. For example, the previously dormant function(s) can be invoked in response to detecting the particular gesture, detecting that the gaze of the user is directed at an assistant device for at least a threshold amount of time, and optionally that the particular gesture and the directed gaze of the user co-occur or occur within a threshold temporal proximity of one another.