Metacognition of Working Memory Performance: Trial-by-Trial Subjective Effects from a New Paradigm

Investigators have begun to examine the fleeting urges and inclinations that subjects experience when performing tasks involving response interference and working memory. Building on this research, we developed a paradigm in which subjects, after learning to press certain buttons when presented with certain letters, are presented with two action-related letters (the memoranda) but must withhold responding (4 s) until cued to emit the response associated with only one of the two letters. In the Congruent condition, the action corresponds to the cue (e.g., memoranda = AB, cue = B, response = B); in the Incongruent condition, the action corresponds to the other item of the memoranda (e.g., memoranda = AB, cue = B, response = A). After each trial, subjects inputted a rating regarding their subjectively experienced “urge to err” on that trial. These introspection-based data revealed that, as found in previous research, urges to err were strongest for incongruent trials. Our findings reveal, first, that subjects can successfully perform this new task, even though it is more complex than that of previous studies, and second, that, in this new paradigm, reliable subjective, metacognitive data can be obtained on a trial-by-trial basis. We hope that our novel paradigm will serve as a foundation for future experimental projects on the relationship between working memory performance and consciousness—an under-explored nexus whose investigation is likely to reveal insights about working memory, cognitive control, and metacognition.

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title: The function of phenomenal states: supramodular interaction theory.
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title: Attention and facilitation: converging information versus inadvertent reading in Stroop task performance.
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Seventeen patients with generalized anxiety disorder and 24 healthy comparison subjects underwent functional MRI while performing an emotional conflict task that involved categorizing facial affect while ignoring overlaid affect label words. Behavioral and neural measures were used to compare trial-by-trial changes in conflict regulation.



Comparison subjects effectively regulated emotional conflict from trial to trial, even though they were unaware of having done so. By contrast, patients with generalized anxiety disorder were completely unable to regulate emotional conflict and failed to engage the pregenual anterior cingulate in ways that would dampen amygdalar activity. Moreover, performance and brain activation were correlated with symptoms and could be used to accurately classify the two groups.



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title: Representations in working memory yield interference effects found with externally-triggered representations.
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title: Neural correlates of the essence of conscious conflict: fMRI of sustaining incompatible intentions
abstract: The study of intrapsychic conflict has long been central to many key theories about the control of behavior. More recently, by focusing on the nature of conflicting processes in the brain, investigators have revealed great insights about controlled versus automatic processes and the nature of self-control. Despite these advances, many theories of cognitive control or self-control remain agnostic about the function of subjective awareness (i.e., basic consciousness). Why people consciously experience some conflicts in the nervous system but not others remains a mystery. One hypothesis is that people become conscious only of conflicts involving competition for the control of skeletal muscle. To test one aspect of this larger hypothesis, in the present study, 14 participants were trained to introspect the feeling of conflict (the urge to make an error during a Stroop color-word interference task) and then were asked to introspect in the same way while sustaining simple compatible and incompatible intentions during fMRI scanning (to move a finger left or right). As predicted, merely sustaining incompatible skeletomotor intentions prior to their execution produced stronger systematic changes in subjective experience than sustaining compatible intentions, as indicated by self-report ratings obtained in the scanner. Similar ratings held for a modified Stroop-like task when contrasting incompatible versus compatible trials also during fMRI scanning. We use subjective ratings as the basis of parametric analyses of fMRI data, focusing a priori on the brain regions involved in action-related urges (e.g., parietal cortex) and cognitive control (e.g., dorsal anterior cingulate cortex, lateral PFC). The results showed that subjective conflict from sustaining incompatible intentions was consistently related to activity in the left post-central gyrus.

title: Neuronal correlates of subjective visual perception.
abstract: Neuronal activity in the superior temporal sulcus of monkeys, a cortical region that plays an important role in analyzing visual motion, was related to the subjective perception of movement during a visual task. Single neurons were recorded while monkeys (Macaca mulatta) discriminated the direction of motion of stimuli that could be seen moving in either of two directions during binocular rivalry. The activity of many neurons was dictated by the retinal stimulus. Other neurons, however, reflected the monkeys' reported perception of motion direction, indicating that these neurons in the superior temporal sulcus may mediate the perceptual experience of a moving object.

title: Neural correlates of thought suppression
abstract: The present report used functional magnetic resonance imaging (fMRI) to examine the neural correlates of thought suppression. Subjects were imaged while alternately (i) attempting to suppress a particular thought, (ii) attempting to suppress all thoughts, or (iii) thinking freely about any thought. Suppression of a particular thought, when compared to the free-thought control condition, revealed greater activation in the anterior cingulate. When the task of suppressing all conscious thoughts was compared to free-thought, a more distributed network of brain regions, including the anterior cingulate and the insula, was activated. These findings are consistent with previous research on cognitive control and may provide potential insights into psychological disorders involving recurring, intrusive thoughts.

title: Response to Comment on "Wandering Minds: The Default Network and Stimulus-Independent Thought"
abstract: Gilbert et al. suggest that activity in the default network may be due to the emergence of stimulus-oriented rather than stimulus-independent thought. Although both kinds of thought likely emerge during familiar tasks, we argue—and report data suggesting—that stimulus-independent thought dominates unconstrained cognitive periods.

title: Separating Sustained From Transient Aspects of Cognitive Control During Thought Suppression
abstract: Cognitive theories of how people regulate their thoughts have suggested the involvement of two control processes that occur over different time courses. These cognitive accounts parallel recent neural models of executive control, which suggest that the prefrontal cortex (PFC) mediates sustained changes in the allocation of control processes, whereas the anterior cingulate cortex (ACC) relays a transient need for additional control. Combining these cognitive and neural models of control, we used recently developed analysis techniques to distinguish transient from sustained changes in brain activation while subjects attempted to suppress an unwanted thought. Results were consistent with both models: Dorsolateral PFC demonstrated sustained increases in activation during attempts at thought suppression, whereas bilateral ACC demonstrated transient increases associated with occurrences of unwanted thoughts. These data support proposals regarding the different contributions made by the PFC and ACC to executive control and provide initial neuroimaging support for dual-process models of how individuals regulate their thoughts.