Relating inter-individual differences in metacognitive performance on different perceptual tasks

Human behavior depends on the ability to effectively introspect about our performance. For simple perceptual decisions, this introspective or metacognitive ability varies substantially across individuals and is correlated with the structure of focal areas in prefrontal cortex. This raises the possibility that the ability to introspect about different perceptual decisions might be mediated by a common cognitive process. To test this hypothesis, we examined whether inter-individual differences in metacognitive ability were correlated across two different perceptual tasks where individuals made judgments about different and unrelated visual stimulus properties. We found that inter-individual differences were strongly correlated between the two tasks for metacognitive ability but not objective performance. Such stability of an individual’s metacognitive ability across different perceptual tasks indicates a general mechanism supporting metacognition independent of the specific task.     

Comparing the temporal stability of self-report and interview assessed personality disorder

Findings from several large-scale, longitudinal studies over the last decade have challenged the long-held assumption that personality disorders (PDs) are stable and enduring. However, the findings, including those from the Collaborative Longitudinal Personality Disorders Study (CLPS; Gunderson et al., 2000), rely primarily on results from semistructured interviews. As a result, less is known about the stability of PD scores from self-report questionnaires, which differ from interviews in important ways (e.g., source of the ratings, item development, and instrument length) that might increase temporal stability. The current study directly compared the stability of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) PD constructs assessed via the Schedule for Nonadaptive and Adaptive Personality (SNAP-2; Clark, Simms, Wu, & Casillas, in press) with those from the Diagnostic Interview for DSM-IV Personality Disorders (Zanarini, Frankenburg, Sickel, & Yong, 1996) over 2 years in a sample of 529 CLPS participants. Specifically, we compared dimensional and categorical representations from both measures in terms of rank-order and mean-level stability. Results indicated that the dimensional scores from the self-report questionnaire had significantly greater rank-order (mean r=.69 vs. .59) and mean-level (mean d=0.21 vs. 0.30) stability. In contrast, categorical diagnoses from the two measures evinced comparable rank-order (mean κ=.38 vs. .37) and mean-level stability (median prevalence rate decrease of 3.5% vs. 5.6%). These findings suggest the stability of PD constructs depends at least partially on the method of assessment and are discussed in the context of previous research and future conceptualizations of personality pathology.     

Auditory mismatch negativity: detecting spectral contrasts in a modulated noise

The ability to detect sinusoidal spectral envelope from an unmodulated (flat) spectrum has shown a strong correlation with speech perception in quiet and noisy listening conditions in normal hearing, hearing-impaired, and cochlear implant users. In this study, the mismatch negativity (MMN) was collected from 10 normal-hearing adult listeners and used to determine if modulation detection thresholds derived electrophysiologically correlate with the psychophysically measured spectral modulation detection thresholds. MMNs were present for most participants with spectral contrasts of 10 and 20 dB, suggesting that the MMN may be a promising neurophysiologic measure of spectral envelope perception when nonbehavioral measures are desired.