Perceptual properties of feedback stimuli influence the feedback‐related negativity in the flanker gambling task

A negative deflection in the event‐related potential is enhanced following error‐ and loss‐related feedback in decision‐making and simple gambling tasks. Researchers have assumed that the perceptual properties of the feedback stimuli are unimportant in explaining these effects. This assumption was tested in the present study through a flanker gambling task, in which the perceptual properties of the feedback were manipulated. Consistent with previous studies, loss elicited a larger feedback‐related negativity ( FRN ) than gain feedback. However, this FRN reward effect was modulated by the perceptual properties of the feedback stimuli. When gain and loss feedback were perceptually similar to each other, the enhancement of the FRN following the loss feedback was smaller compared to when the gain and loss feedback were different from each other. In addition, incongruent feedback elicited a larger FRN than congruent feedback; this FRN congruency effect was larger following gain than loss feedback. These results suggested that perceptual properties of the feedback stimuli play a role in the elicitation of the FRN .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108013/1/psyp12216.pd

A Close Companion Search Around L Dwarfs Using Aperture Masking Interferometry and Palomar Laser Guide Star Adaptive Optics

We present a close companion search around 16 known early L dwarfs using aperture masking interferometry with Palomar laser guide star adaptive optics (LGS AO). The use of aperture masking allows the detection of close binaries, corresponding to projected physical separations of 0.6-10.0 AU for the targets of our survey. This survey achieved median contrast limits of ΔK ~ 2.3 for separations between 1.2λ/D-4λ/D and ΔK ~ 1.4 at 2/3λ/D. We present four candidate binaries detected with moderate-to-high confidence (90%-98%). Two have projected physical separations less than 1.5 AU. This may indicate that tight-separation binaries contribute more significantly to the binary fraction than currently assumed, consistent with spectroscopic and photometric overluminosity studies. Ten targets of this survey have previously been observed with the Hubble Space Telescope as part of companion searches. We use the increased resolution of aperture masking to search for close or dim companions that would be obscured by full aperture imaging, finding two candidate binaries. This survey is the first application of aperture masking with LGS AO at Palomar. Several new techniques for the analysis of aperture masking data in the low signal-to-noise regime are explored

Time-frequency PCA of event-related EEG changes in the orienting reflex

Abstract presented at the 17th World Congress of Psychophysiology (IOP2014) of the International Organization of Psychophysiology (IOP) Hiroshima, Japan, September 23rd to 27th, 201

Psychopathy, Phenotypic Boldness, and Affective Modulation of the Blink Reflex and P3 Responses to Acoustic Startle Probes during Aversive Images

The triarchic model of psychopathy conceptualizes this disorder in terms of distinct phenotypic constructs of disinhibition, meanness, and boldness. The boldness facet of psychopathy (reflecting social dominance, resilience to stress, and venture-someness) is hypothesized to reflect fearless temperament. The current study examined relations between the boldness facet of psychopathy and affective/attentio- nal processing of IAPS picture stimuli. 145 adult male offenders, assessed for psychopathic traits via the PCL-R and an interview measure of boldness, completed an affective picture-viewing task in which eyeblink and event-related potential responses to acoustic startle probes were collected. Boldness predicted diminished startle potentiation during aversive picture viewing, and mediated the observed asso-ciation between PCL-R psychopathy scores and aversive blink potentiation. To extend findings for startle blink, analyses of P3 brain responses to noise probe stimuli (known to be modulated by foreground attention-allocation) will be undertaken to evaluate alternative hypotheses as follows: (H0) boldness will be unrelated to differences in attentional processing of affective foregrounds, indicating a primary deficit in emotional reactivity; (H1) high boldness will be associated with reduced attentional modulation of probe-P3 for aversive images, indicating a role of attention in emotional reactivity deficits

Event-related EEG time-frequency PCA and the orienting reflex to auditory stimuli

We recently reported an auditory habituation series with counterbalanced indifferent and significant (counting) instructions. Time-frequency (t-f) analysis of electrooculogram-corrected EEG was used to explore event-related synchronization (ERS)/desynchronization (ERD) in four EEG bands using arbitrarily selected time epochs and traditional frequency ranges. ERS in delta, theta, and alpha, and subsequent ERD in theta, alpha, and beta, showed substantial decrement over trials, yet effects of stimulus significance (count vs. no-task) were minimal. Here, we used principal components analysis (PCA) of the t-f data to investigate the natural frequency and time combinations involved in such stimulus processing. We identified four ERS and four ERD t-f components: six showed decrement over trials, four showed count \u3e no-task effects, and six showed SignificancexTrial interactions. This increased sensitivity argues for the wider use of our data-driven t-f PCA approach

Are excluding e-cigarettes a loophole in the smokefree public housing rule?

The U.S. Department of Housing and Urban Development (HUD) required all Public Housing Authorities to become smokefree in July 2018, following an 18-month implementation period that began February 2017. The HUD rule included all combustible tobacco products; e-cigarettes were not included. This purpose of this study is to characterize e-cigarette use overall and initiation after the implementation of the smokefree rule among tobacco users living in public housing. Data were collected from 396 adult (18+ years) current tobacco users at the time of rule implementation residing in the District of Columbia Housing Authority between July 2018 and November 2021. Measures include e-cigarette use, age of initiation, reasons for e-cigarette use, e-cigarette use susceptibility (among non-users), and sociodemographic characteristics. Descriptive and crosstab statistics were calculated to characterize e-cigarette use. Nearly-one-quarter of tobacco users reported lifetime use of e-cigarettes (24 %, n = 95) and 4.8 % (n = 19) indicated past 30-day e-cigarette use. Of the lifetime users, twenty-two (23.2 %) initiated their use after the smoke-free rule went into effect, with only two of those residents indicating they did so because of the rule. Of those who never used an e-cigarette, 23.5 % (n = 70) indicated being curious about e-cigarettes and 10.7 % (n = 40) said they may use e-cigarettes in the next year. Results indicate low use of e-cigarette products and low uptake due to the rule. Few tobacco users who never used e-cigarettes indicated intentions to use. Results suggest that omitting e-cigarettes from the HUD rule has not led to significant use of these products in this sample

Event-related EEG time-frequency PCA and the orienting reflex to auditory stimuli

We recently reported an auditory habituation series with counterbalanced indifferent and significant (counting) instructions. Time-frequency (t-f) analysis of electrooculogram-corrected EEG was used to explore event-related synchronization (ERS)/desynchronization (ERD) in four EEG bands using arbitrarily selected time epochs and traditional frequency ranges. ERS in delta, theta, and alpha, and subsequent ERD in theta, alpha, and beta, showed substantial decrement over trials, yet effects of stimulus significance (count vs. no-task) were minimal. Here, we used principal components analysis (PCA) of the t-f data to investigate the natural frequency and time combinations involved in such stimulus processing. We identified four ERS and four ERD t-f components: six showed decrement over trials, four showed count > no-task effects, and six showed Significance X Trial interactions. This increased sensitivity argues for the wider use of our data-driven t-f PCA approach

Separating cognitive processes with principal components analysis of EEG time-frequency distributions

Measurement of EEG event-related potential (ERP) data has been most commonly undertaken in the time-domain, which can be complicated to interpret when separable activity overlaps in time. When the overlapping activity has distinct frequency characteristics, however, time-frequency (TF) signal processing techniques can be useful. The current report utilized ERP data from a cognitive task producing typical feedback-related negativity (FRN) and P300 ERP components which overlap in time. TF transforms were computed using the binomial reduced interference distribution (RID), and the resulting TF activity was then characterized using principal components analysis (PCA). Consistent with previous work, results indicate that the FRN was more related to theta activity (3-7 Hz) and P300 more to delta activity (below 3 Hz). At the same time, both time-domain measures were shown to be mixtures of TF theta and delta activity, highlighting the difficulties with overlapping activity. The TF theta and delta measures, on the other hand, were largely independent from each other, but also independently indexed the feedback stimulus parameters investigated. Results support the view that TF decomposition can greatly improve separation of overlapping EEG/ERP activity relevant to cognitive models of performance monitoring