Insuppressible cognitions in the reflexive imagery task: Insights and future directions

In 1959, Neal Miller made the bold claim that the Stimulus-Response, Behaviorist models of that era were describing the way in which stimuli lead to the entry of contents into consciousness ("entry," for short). Today, researchers have begun to investigate the link between external stimuli and involuntary entry, using paradigms such as the reflexive imagery task (RIT), the focus of our review. The RIT has revealed that stimuli can elicit insuppressible entry of high-level cognitions. Knowledge of the boundary conditions of the RIT effect illuminates the limitations of involuntary processes and the role of consciousness in the regulation of behavior. We review the boundary conditions of this paradigm as well as its systematic effects. Systematic effects are unlikely to be due to experimental demand. While reviewing each effect, we consider its theoretical implications. In addition, throughout our review, we discuss future directions for the study of insuppressible entry using the RIT. Last, we discuss a theoretical development (passive frame theory) that stems from the RIT and illuminates how involuntary entry and encapsulation, though at times disadvantageous for the actor, are essential for adaptive action selection during the course of ontogeny.

Reversible-figure perception: Why is voluntary control limited?

Observers can voluntarily avoid reversals of an ambiguous, reversible figure, extending the duration of an intended percept. This is usually attributed to high-level, top-down attentional processes. However, voluntary control is limited. Reversals occur despite attempts to avoid them. In two experiments, observers demonstrated significant, but limited, voluntary control over Necker cube perception. Cube size and cube completeness, variables associated with stimulus-driven processes involving neural adaptation, influenced the frequency of reversals regardless of observers' intentions. Results are consistent with the hybrid hypothesis that both top-down and bottom-up processes contribute to Necker-cube perception and support the hypothesis that the contribution of bottom-up processes is responsible for the limitation on voluntary control.

EEG Correlates of Involuntary Cognitions in the Reflexive Imagery Task

The Reflexive Imagery Task (RIT) reveals that the activation of sets can result in involuntary cognitions that are triggered by external stimuli. In the basic RIT, subjects are presented with an image of an object (e.g., CAT) and instructed to not think of the name of the object. Involuntary subvocalizations of the name (the RIT effect) arise on roughly 80% of the trials. We conducted an electroencephalography (EEG) study to explore the neural correlates of the RIT effect. Subjects were presented with one object at a time in one condition and two objects simultaneously in another condition. Five regions were defined by electrode sites: frontal (F3-F4), parietal (P3-P4), temporal (T3-T4), right hemisphere (F4-P4), and left hemisphere (F3-P3). We focused on the alpha (8-13 Hz), beta (13-30 Hz), delta (0.01-4 Hz), and theta (4-8 Hz) frequencies.

Involuntary Entry Into Consciousness From the Activation of Sets: Object Counting and Color Naming

High-level cognitions can enter consciousness through the activation of certain action sets and the presentation of external stimuli (“set-based entry,” for short). Set-based entry arises in a manner that is involuntary and systematic. In the Reflexive Imagery Task, for example, subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We examined whether or not set-based entry can also occur in the case of involuntary counting. Subjects in Experiment 1A were instructed to not count the number of objects presented in an array. Involuntary counting arose on a high proportion of the trials (a mean proportion of ∼0.90) for stimulus arrays having 2–5 objects, and such counting arose less frequently across trials when the array consisted of 6–10 objects (a mean proportion of ∼0.21). The data from Experiment 1B revealed that, when people choose to perform Set X, they also experience thoughts about an unselected Set (Set Y). Subjects were trained on one set (e.g., to “color name”) and then, when presented with stimuli, were given the choice to perform the trained set or a novel set. Consistent with theories proposing that the conscious contents represent several potential action plans, subjects were equally likely to experience set-related imagery or set-unrelated imagery. Our findings regarding set-based entry are relevant to many subfields of psychology and neuroscience (e.g., the study of high-level mental processes, attention, imagery, and action control).

The reflexive imagery task: An experimental paradigm for neuroimaging

High-level cognitions can be triggered into consciousness through the presentation of external stimuli and the activation of certain action sets. These activations arise in a manner that is involuntary, systematic and nontrivial. For example, in the Reflexive Imagery Task (RIT), subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We review the findings from this paradigm, discuss neural findings that are relevant to the RIT, and present new data that further corroborate the reliability and robustness of the RIT, a paradigm that could be coupled with neuroimaging technologies. We developed an RIT variant in which two, non-focal objects are presented simultaneously. In previous RITs, visual objects were presented only one at a time, in the center of the screen, and subjects were instructed to focus on the center of the screen, where these objects were presented. Replicating the RIT effect, involuntary subvocalizations still occurred on a high proportion of trials (M = 0.78). An RIT effect arose for both objects on a considerable proportion of the trials (M = 0.35). These findings were replicated in a second experiment having a different sample of subjects. Our findings are relevant to many subfields of neuroscience (e.g., the study of high-level mental processes, attention, imagery and action control).