The neurocognitive basis of metamemory: Using the N400 to study the contribution of fluency to judgments of learning

The N270 as an index of consumer commodity color preference in the S1-S2 paradigm

Introduction

Affective decision-making is a prominent topic in consumer psychology research, with its core assumption being that consumers tend to purchase brands and commodities they like. However, the reasons behind why we develop emotional responses of liking or disliking toward certain commodities, as well as what the underlying neural mechanisms are, remain largely unknown.

Methods

This study utilized the S1-S2 paradigm in an experiment wherein S1 presented 12 types of commodities and S2 displayed 48 distinct colored squares. Participants were instructed to assess whether they "Like" or "Dislike" the commodity in S1, which was colored with the S2 color. Electroencephalogram (EEG) recordings were obtained during the reaction process and subsequently analyzed to examine the components of S2-induced event-related potentials (ERPs).

Results

The analysis revealed that S2 elicited a significant N270 in the prefrontal scalp area under both the "Like" and "Dislike" conditions. Interestingly, the amplitude of the N270 was significantly higher during the "Dislike" condition compared to the "Like" condition.

Discussion

The N270 component was shown to reflect the conflict in physical attributes between S1 and S2, as well as the conflict between commodity and color. This highlights the potential utility of this component as an objective EEG indicator of consumer commodity color preferences in future marketing research.

Comparing event-related potentials of retrospective and prospective metacognitive judgments during episodic and semantic memory

It is unclear whether metacognitive judgments are made on the basis of domain-generality or domain-specificity. In the current study, we compared both behavioral and event-related potential (ERP) correlates of retrospective (retrospective confidence judgments: RCJs), and prospective (feeling of knowing: FOK) metacognitive judgments during episodic and semantic memory tasks in 82 participants. Behavioral results indicated that FOK judgments reflect a domain-specific process, while RCJ reflect a domain-general process. RCJ and FOK judgments produced similar ERP waveforms within the memory tasks, but with different temporal dynamics; thus supporting the hypothesis that retrospective and prospective metacognitive judgments are distinct processes. Our ERP results also suggest that metacognitive judgments are linked to distributed neural substrates, rather than purely frontal lobe functioning. Furthermore, the role of intra-subject and inter-subject differences in metacognitive judgments across and within the memory tasks are highlighted.

An Event-Related Potential Study on Differences Between Higher and Lower Easy of Learning Judgments: Evidence for the Ease-of-Processing Hypothesis

Easy of learning (EOL) judgments occur before active learning begins, and it is a prediction of how difficult it will be to learn new material in future learning. This study compared the amplitude of event-related potential (ERP) components and brain activation regions between high and low EOL judgments by adopting ERPs with a classical EOL judgment paradigm, aiming to confirm the ease-of-processing hypothesis. The results showed that (1) the magnitudes of EOL judgments are affected by encoding fluency cues, and the judgment magnitude increases with encoding fluency; (2) low EOL judgments are associated with higher N400 amplitude at the left superior frontal gyrus (SFG) and left middle frontal gyrus (MFG). High EOL judgments showed enlarged slow-wave (600–1,000 ms) potentials than low EOL judgments at the left medial temporal lobe (MTL), right ventromedial prefrontal cortex (VMPFC), and dorsolateral prefrontal cortex (DLPFC). Our results support the ease-of-processing hypothesis, particularly, by affirming that EOL judgments are affected by encoding fluency in two processing stages. N400 reflects the process of acquiring encoding fluency cues, while slow-wave indicates that individuals use encoding fluency cues for metacognitive monitoring.

Brain activities of reconsolidation: Nuances in post-retrieval interference led to optimal alterations of episodic memories

When memories are reactivated, they enter a period of instability in which they can be affected by a variety of follow-up manipulations. The existence of this type of memory reconsolidation offers the potential for clinical interventions of maladaptive memory. However, such potential cannot be fully exploited until the internal mechanisms of memory changes via reconsolidation are better understood. In the current study, we used a three-day AB-AC paradigm that included self-referential simulation processing and employed electroencephalogram (EEG) techniques to explore how post-retrieval updates of episodic memory come about. Behaviorally, we found that reactivation alongside interference learning (ReI-L, AB-AC, n = 52) can produce much more false memories compared to no reactivation new learning (New-L, AB-DC, n = 31) and reactivation repetitive learning (Rep-L, AB-AB. n = 30). More importantly, ERP results revealed that trials from ReI-L in which memory distortions subsequently occurred showed an observable (compared to the new-learning without memory reactivation) but attenuated (compared to trials associating with later intact memory) amplitude of frontal N400, indicating a moderate level of early conflict reactivation is necessary to trigger crucial memory instability. In addition, to promote optimal distortion of the original memory, a sufficient later constructional processing is also required, reflecting in these intrusive/later false trials showed a larger amplitude of late posterior negativity (LPN). A linear classifier employing neuro features of FN400 and LPN during the reconsolidation phase could predict the original memory retention with 72% accuracy. The present findings indicate that nuance in post-retrieval interference, moderate conflict with protracted construction can lead to optimal alterations of episodic memories.

Evidence for an Age-Related Positivity Effect in Metacognitive Judgments

OBJECTIVES

If older adults (OAs) are focused on emotionally meaningful goals in late life, they should demonstrate memory biases for positive stimuli over neutral and negative stimuli and, arguably, these cognitive biases should be reflected in their metacognitive judgments of learning (JOLs). To address this question, we examined age differences in metacognitive monitoring of emotionally valenced stimuli.

METHOD

Younger adults (YAs) and OAs (N = 85) studied positive, neutral, and negative words and made immediate JOLs, followed by a 2-alternative forced choice (2AFC) recognition memory task.

RESULTS

Analyses of JOLs revealed evidence for a positivity effect in metacognitive judgments for OAs and an emotional salience effect in YAs. YAs recognized more words than OAs, but valence did not affect number of words recognized and did not moderate age differences in memory (p = .055). Memory monitoring as measured by resolution accuracy was equivalent in YAs and OAs. Positive affect was higher and negative affect was lower in OAs relative to YAs, lending additional evidence to the emergence of a positive orientation in older adulthood.

DISCUSSION

These results provide intriguing and novel support for the positivity effect in the domain of metacognitive aging, adding to what is known in memory, attention, and emotion domains. Our findings fall squarely within socioemotional and metacognitive theoretical frameworks from which they were derived. We discuss research directions that might identify mechanisms by which affective states and stimuli interact to produce metacognitive outcomes in late life.

Perceptual Fluency Affects Judgments of Learning Non-analytically and Analytically Through Beliefs About How Perceptual Fluency Affects Memory

Perceptual fluency is generally thought to affect judgments of learning (JOLs) non-analytically. However, some studies suggested that perceptual fluency may also affect JOLs analytically based on beliefs about the relationship between perceptual fluency and memory performance. The present study aimed to investigate how perceptual fluency affects JOLs. In Experiment 1, participants performed a continuous identification task and a JOLs task to determine whether perceptual fluency affects JOLs. In Experiment 2, we manipulated participants’ beliefs about how perceptual fluency affects memory to explore whether perceptual fluency affects JOLs through belief-based analysis. In Experiment 3, we explored whether participants who believed neither perceptual fluency nor font size affected memory performance still offered higher JOLs to large words than to small words, to explore whether perceptual fluency affects JOLs non-analytically. In Experiment 4, participants performed a continuous identification-JOLs task, and then they performed an observation task to measure their beliefs about fluency and memory. The results of the four experiments suggested that perceptual fluency affects JOLs both non-analytically and analytically based on beliefs about the relationship between perceptual fluency and memory performance.

Toward a Neurocognitive Understanding of the Algorithms That Underlie Metamemory Judgments

Abstract. Neurocognitive research on metamemory thus far has mostly focused on localizing brain regions that track metacognitive judgments and distinguishing metacognitive processing from primary cognition. With much known about the localization of metamemory in the brain, there is a growing opportunity to develop a more algorithmic characterization of the brain processes underlying metamemory. We briefly review some current neurocognitive metamemory research, including relevant brain regions and theories about their role in metamemory. We review some computational neuroimaging approaches and, as an illustrative example, describe their use in studies on the delayed-JOL (judgments of learning) effect. Finally, we discuss how researchers might apply computational approaches to several unresolved questions in the behavioral metamemory literature. Such research could provide a bridge between cognitive and neurocognitive research on metamemory and provide novel insights into the algorithms underlying metamemory judgments, thus informing theory and methodology in both areas.