New research is beginning to reveal that, though action inclinations can be suppressed behaviorally, they often cannot be suppressed mentally (Bargh & Morsella, 2008, Perspectives on Psychological Science). Consider that, when holding one’s breath or when in some other ‘pain for gain’ scenario (e.g., carrying a hot dish of food), one can suppress overt behavior (e.g., inhaling or dropping a hot dish) but one cannot suppress the urges associated with these action tendencies (e.g., the urge to inhale or to drop the dish, respectively). Similarly, when presented with an enticing stimulus such as a cupcake, one may suppress the act of reaching for it and eating it (because that is what the doctor tells us to do), but the inclination to do these things cannot be diminished by sheer will, at least not without difficulty.
It is ironic that the stimulus-response models of behavior proposed by the Behaviorists failed at explaining and predicting overt behavior, but they capture in some sense much of what goes on in consciousness—the very phenomenon that Behaviorists considered to fall outside of their scientific purview.
This observation is consistent with the theorizing by the great Hermann von Helmholtz, who proposed that conscious contents arise from the workings of sophisticated, ‘unconscious inferences.’ These inferences are not under one’s control. He held that these inferences are not at play just in the creation of ‘low-level’ perceptual contents (e.g., of depth perception), but also during complicated processes such as automatic word reading, in which a visual stimulus (e.g., the word HOUSE) automatically activates a conscious, sound-based phonological representation (e.g., /haus/) in one’s mind. Helmholtz thought it was curious that such an incidental stimulus could have such an influence on the conscious mind, unintentionally. Importantly, such unconscious processes operate upon 'supraliminal' (conscious) representations (see "Freud's Unconscious Was Not a Subliminal One").
There is a new paradigm, the Reflexive Imagery Task that builds on these observations and also on the pioneering research by Daniel Wegner and others (e.g., Peter Gollwitzer). In this experimental paradigm, it is demonstrated that urges and other action options enter consciousness in a predictable, systematic, and surprisingly unintentional manner. (There many variants of this paradigm, each with striking effects.) For the purposes of illustration, you will be presented with a simplified demonstration of the curious RIT phenomenon. Momentarily, you will be presented with an object enclosed within parentheses. Your task is to (a) not name the object aloud (easy to do) and (b) not subvocalize the name of the object (not so easy to do). (Subvocalizing is when one ‘talks in one’s head.’) Well, here is the object ( ∆ ). It is interesting that, though you probably succeeded at not uttering the object name aloud ("triangle"), you most likely could not silence your inner voice. Helmholtz and others thought long and hard about this curious fact, one which reveals much about action, imagery, and consciousness.