Test-retest reliability of spectral parameterization by 1/f characterization using SpecParam.

SpecParam (formally known as FOOOF) allows for the refined measurements of electroencephalography periodic and aperiodic activity, and potentially provides a non-invasive measurement of excitation: inhibition balance. However, little is known about the psychometric properties of this technique. This is integral for understanding the usefulness of SpecParam as a tool to determine differences in measurements of cognitive function, and electroencephalography activity. We used intraclass correlation coefficients to examine the test-retest reliability of parameterized activity across three sessions (90 minutes apart and 30 days later) in 49 healthy young adults at rest with eyes open, eyes closed, and during three eyes closed cognitive tasks including subtraction (Math), music recall (Music), and episodic memory (Memory). Intraclass correlation coefficients were good for the aperiodic exponent and offset (intraclass correlation coefficients > 0.70) and parameterized periodic activity (intraclass correlation coefficients > 0.66 for alpha and beta power, central frequency, and bandwidth) across conditions. Across all three sessions, SpecParam performed poorly in eyes open (40% of participants had poor fits over non-central sites) and had poor test-retest reliability for parameterized periodic activity. SpecParam mostly provides reliable metrics of individual differences in parameterized neural activity. More work is needed to understand the suitability of eyes open resting data for parameterization using SpecParam.

Medication-invariant resting aperiodic and periodic neural activity in Parkinson's disease.

Parkinson's disease (PD) has been associated with greater total power in canonical frequency bands (i.e., alpha, beta) of the resting electroencephalogram (EEG). However, PD has also been associated with a reduction in the proportion of total power across all frequency bands. This discrepancy may be explained by aperiodic activity (exponent and offset) present across all frequency bands. Here, we examined differences in the eyes-open (EO) and eyes-closed (EC) resting EEG of PD participants (N = 26) on and off medication, and age-matched healthy controls (CTL; N = 26). We extracted power from canonical frequency bands using traditional methods (total alpha and beta power) and extracted separate parameters for periodic (parameterized alpha and beta power) and aperiodic activity (exponent and offset). Cluster-based permutation tests over spatial and frequency dimensions indicated that total alpha and beta power, and aperiodic exponent and offset were greater in PD participants, independent of medication status. After removing the exponent and offset, greater alpha power in PD (vs. CTL) was only present in EO recordings and no reliable differences in beta power were observed. Differences between PD and CTL in the resting EEG are likely driven by aperiodic activity, suggestive of greater relative inhibitory neural activity and greater neuronal spiking. Our findings suggest that resting EEG activity in PD is characterized by medication-invariant differences in aperiodic activity which is independent of the increase in alpha power with EO. This highlights the importance of considering aperiodic activity contributions to the neural correlates of brain disorders.

Efficacy of neurostimulation across mental disorders: systematic review and meta-analysis of 208 randomized controlled trials.

Non-invasive brain stimulation (NIBS), including transcranial magnetic stimulation (TMS), and transcranial direct current stimulation (tDCS), is a potentially effective treatment strategy for a number of mental conditions. However, no quantitative evidence synthesis of randomized controlled trials (RCTs) of TMS or tDCS using the same criteria including several mental conditions is available. Based on 208 RCTs identified in a systematic review, we conducted a series of random effects meta-analyses to assess the efficacy of NIBS, compared to sham, for core symptoms and cognitive functioning within a broad range of mental conditions. Outcomes included changes in core symptom severity and cognitive functioning from pre- to post-treatment. We found significant positive effects for several outcomes without significant heterogeneity including TMS for symptoms of generalized anxiety disorder (SMD = -1.8 (95% CI: -2.6 to -1), and tDCS for symptoms of substance use disorder (-0.73, -1.00 to -0.46). There was also significant effects for TMS in obsessive-compulsive disorder (-0.66, -0.91 to -0.41) and unipolar depression symptoms (-0.60, -0.78 to -0.42) but with significant heterogeneity. However, subgroup analyses based on stimulation site and number of treatment sessions revealed evidence of positive effects, without significant heterogeneity, for specific TMS stimulation protocols. For neurocognitive outcomes, there was only significant evidence, without significant heterogeneity, for tDCS for improving attention (-0.3, -0.55 to -0.05) and working memory (-0.38, -0.74 to -0.03) in individuals with schizophrenia. We concluded that TMS and tDCS can benefit individuals with a variety of mental conditions, significantly improving clinical dimensions, including cognitive deficits in schizophrenia which are poorly responsive to pharmacotherapy.

There is a party in my head and no one is invited: Resting-state electrocortical activity and solitude.

OBJECTIVE: What are the motivational underpinnings of solitude? We know from self-report studies that increases in solitude are associated with drops in approach motivation and rises in avoidance motivation, but only when solitude is experienced as non-self-determined (i.e., non-autonomous). However, the extent to which individual differences in solitude relate to neurophysiological markers of approach-avoidance motivation derived from resting-state electroencephalogram (EEG) is unknown. These markers are Frontal Alpha Asymmetry, beta suppression, and midline Posterior versus Frontal EEG Theta Activity. METHOD: We assessed the relation among individual differences in the reasons for solitude (i.e., preference for solitude, motivation for solitude), approach-avoidance motivation, and resting-state EEG markers of approach-avoidance motivation (N = 115). RESULTS: General preference for solitude was negatively related to approach motivation, observed in both self-reported measures and EEG markers of approach motivation. Self-determined solitude was positively related to both self-reported approach motivation and avoidance motivation in the social domain (i.e., friendship). Non-self-determined solitude was negatively associated with self-reported avoidance motivation. CONCLUSION: This research was a preliminary attempt to address the neurophysiological underpinnings of solitude in the context of motivation.

Crunch: integrated processing and modeling of ChIP-seq data in terms of regulatory motifs.

Although ChIP-seq has become a routine experimental approach for quantitatively characterizing the genome-wide binding of transcription factors (TFs), computational analysis procedures remain far from standardized, making it difficult to compare ChIP-seq results across experiments. In addition, although genome-wide binding patterns must ultimately be determined by local constellations of DNA-binding sites, current analysis is typically limited to identifying enriched motifs in ChIP-seq peaks. Here we present Crunch, a completely automated computational method that performs all ChIP-seq analysis from quality control through read mapping and peak detecting and that integrates comprehensive modeling of the ChIP signal in terms of known and novel binding motifs, quantifying the contribution of each motif and annotating which combinations of motifs explain each binding peak. By applying Crunch to 128 data sets from the ENCODE Project, we show that Crunch outperforms current peak finders and find that TFs naturally separate into "solitary TFs," for which a single motif explains the ChIP-peaks, and "cobinding TFs," for which multiple motifs co-occur within peaks. Moreover, for most data sets, the motifs that Crunch identified de novo outperform known motifs, and both the set of cobinding motifs and the top motif of solitary TFs are consistent across experiments and cell lines. Crunch is implemented as a web server, enabling standardized analysis of any collection of ChIP-seq data sets by simply uploading raw sequencing data. Results are provided both in a graphical web interface and as downloadable files.

Electrocortical Effects of Acetaminophen during Emotional Picture Viewing, Cognitive Control, and Negative Feedback.

Acetaminophen, the active ingredient in Tylenol, may have psychological effects, such as reducing social and emotional pain. The current study (N = 173) used electroencephalography (EEG) to extend past research on acetaminophen. Healthy undergraduate students (64.7% women, age M = 18.15, SD = 3.33) were randomly assigned to ingest 1,000 mg of acetaminophen or placebo before completing emotional picture viewing (n = 143), a flanker task (n = 69), and a probabilistic learning task (n = 143) while EEG was recorded. (Sample sizes used for the analyses of each task differ from the total N due to data loss.) We observed standard event-related potentials (ERPs), including emotion-modulated late positive potentials during picture viewing and feedback-related negativity during feedback on the probabilistic learning task. We also observed standard error-related and conflict-related ERPs in the flanker task but could not adequately assess acetaminophen's effect on flanker ERPs due to excessive data loss. Acetaminophen did not alter any of the ERPs, in contrast to predictions based on prior research. Exploratory analyses revealed that acetaminophen reduced the relationship between trait behavioral inhibition system sensitivity and emotion-modulated late positive potentials. Together these findings suggest that a standard dose of acetaminophen did not reliably alter neural indicators of emotional or feedback processing. Instead, preliminary findings from our study suggested that a more nuanced relationship may exist between acetaminophen and individual differences in emotional processing, although this latter finding calls for further replication.

Amygdala subnuclei volume in bipolar spectrum disorders: Insights from diffusion-based subsegmentation and a high-risk design.

Amygdala abnormalities are widely documented in bipolar spectrum disorders (BSD). Amygdala volume typically is measured after BSD onset; thus, it is not known whether amygdala abnormalities predict BSD risk or relate to the disorder. Additionally, past literature often treated the amygdala as a homogeneous structure, and did not consider its distinct subnuclei and their differential connectivity to other brain regions. To address these issues, we used a behavioral high-risk design and diffusion-based subsegmentation to examine amygdala subnuclei among medication-free individuals with, and at risk for, BSD. The behavioral high-risk design (N = 114) included low-risk (N = 37), high-risk (N = 47), and BSD groups (N = 30). Diffusion-based subsegmentation of the amygdala was conducted to determine whether amygdala volume differences related to particular subnuclei. Individuals with a BSD diagnosis showed greater whole, bilateral amygdala volume compared to Low-Risk individuals. Examination of subnuclei revealed that the BSD group had larger volumes compared to the High-Risk group in both the left medial and central subnuclei, and showed larger volume in the right lateral subnucleus compared to the Low-Risk group. Within the BSD group, specific amygdala subnuclei volumes related to time since first episode onset and number of lifetime episodes. Taken together, whole amygdala volume analyses replicated past findings of enlargement in BSD, but did not detect abnormalities in the high-risk group. Examination of subnuclei volumes detected differences in volume between the high-risk and BSD groups that were missed in the whole amygdala volume. Results have implications for understanding amygdala abnormalities among individuals with, and at risk for, a BSD.

Shifts in attentional scope modulate event-related potentials evoked by reward.

Emotions broaden or narrow the scope of attention in order to facilitate adaptive responses in threatening and rewarding contexts. In the current study, rather than asking how emotions influence attentional scope, we considered the possibility that the relationship between attentional breadth and emotion is bidirectional by asking whether shifts in attentional scope alter emotional processes using an event-related potential (ERP) paradigm. Participants (N = 30) completed a modified version of a Monetary Incentive Delay (MID) task, wherein their attention was either narrowed or broadened as they attempted to win rewards. Behaviorally, narrowing attention improved task performance in the form of reduced errors and increased monetary winnings. During cue processing, narrowing (compared to broadening) attention reduced the Cue-P3 (irrespective of cue type). During feedback processing, narrowing (compared to broadening) attention reduced the Feedback-P3 to monetary wins and increased the Feedback-P2 and the Feedback-P3 to monetary non-wins. Results highlight complexity and bidirectionality in the relationship between attentional scope and affective processes.

Correction to: After-effects of self-control: The reward responsivity hypothesis.

The article After-effects of self-control: The reward responsivity hypothesis, written by Nicholas J. Kelley, Anna J. Finley, Brandon J. Schmeichel was originally published electronically on the publisher's internet portal (currently SpringerLink) on 23 January 2019 with open access.

After-effects of self-control: The reward responsivity hypothesis.

Exercising self-control can be phenomenologically aversive. Insofar as individuals strive to maintain a positive emotional state, one consequence of exercising self-control may thus be a temporarily tuning toward or amplification of reward-related impulses (perhaps arising to countermand the aversive feelings that stem from self-control). Reward-relevant after-effects are relatively underappreciated in self-control research. In the current paper, we review theory and research pertaining to the idea that exercising self-control increases reward responsivity. First, we review theoretical models of self-control focusing on the relationship between control systems and reward systems. Second, we review behavioral studies regarding the effects of exercising self-control on subsequent reactivity to food, money, drugs, and positive emotional images. Third, we review findings from functional neuroimaging and electroencephalographic research pertaining to the reward responsivity hypothesis. We then call for additional research to integrate how, when, and under what circumstances self-control exertion influences reward processing. Such an endeavor will help to advance research and theory on self-control by offering a more precise characterization of the dynamic interactions between control systems and reward systems.

Emotional content impacts how executive function ability relates to willingness to wait and to work for reward.

Research has demonstrated that better value-based decision making (e.g., waiting or working for rewards) relates to greater executive function (EF) ability. However, EF is not a static ability, but is influenced by the emotional content of the task. As such, EF ability in emotional contexts may have unique associations with value-based decision making, in which costs and benefits are explicit. Participants (N = 229) completed an EF task (with both negative and neutral task conditions) and two value-based decision-making tasks. Willingness to wait and to work were evaluated in separate path models relating the waiting and working conditions to the EF conditions. Willingness to wait and willingness to work showed distinct relationships with EF ability: Greater EF ability on a negative, but not on a neutral, EF task was related to a willingness to wait for a reward, whereas greater EF ability across both EF tasks was related to a greater willingness to work for a reward. EF ability on a negative EF task showed an inverted-U relationship to willingness to wait for reward, and was most related to willingness to wait at a 6-month delay. Greater EF, regardless of whether the task was negative or neutral, was related to a greater willingness to work when reward was uncertain (50%) or was likely (88%), but not when reward was unlikely (12%). This study suggests that the emotional content of value-based decisions impacts the relationship between EF ability and willingness to wait or to work for reward.

A large-scale, in vivo transcription factor screen defines bivalent chromatin as a key property of regulatory factors mediating Drosophila wing development.

Transcription factors (TFs) are key regulators of cell fate. The estimated 755 genes that encode DNA binding domain-containing proteins comprise ∼ 5% of all Drosophila genes. However, the majority has remained uncharacterized so far due to the lack of proper genetic tools. We generated 594 site-directed transgenic Drosophila lines that contain integrations of individual UAS-TF constructs to facilitate spatiotemporally controlled misexpression in vivo. All transgenes were expressed in the developing wing, and two-thirds induced specific phenotypic defects. In vivo knockdown of the same genes yielded a phenotype for 50%, with both methods indicating a great potential for misexpression to characterize novel functions in wing growth, patterning, and development. Thus, our UAS-TF library provides an important addition to the genetic toolbox of Drosophila research, enabling the identification of several novel wing development-related TFs. In parallel, we established the chromatin landscape of wing imaginal discs by ChIP-seq analyses of five chromatin marks and RNA Pol II. Subsequent clustering revealed six distinct chromatin states, with two clusters showing enrichment for both active and repressive marks. TFs that carry such "bivalent" chromatin are highly enriched for causing misexpression phenotypes in the wing, and analysis of existing expression data shows that these TFs tend to be differentially expressed across the wing disc. Thus, bivalently marked chromatin can be used as a marker for spatially regulated TFs that are functionally relevant in a developing tissue.

Out of sight, out of mind: racial retrieval cues increase the accessibility of social justice concepts.

Photographs provide critical retrieval cues for personal remembering, but few studies have considered this phenomenon at the collective level. In this research, we examined the psychological consequences of visual attention to the presence (or absence) of racially charged retrieval cues within American racial segregation photographs. We hypothesised that attention to racial retrieval cues embedded in historical photographs would increase social justice concept accessibility. In Study 1, we recorded gaze patterns with an eye-tracker among participants viewing images that contained racial retrieval cues or were digitally manipulated to remove them. In Study 2, we manipulated participants' gaze behaviour by either directing visual attention toward racial retrieval cues, away from racial retrieval cues, or directing attention within photographs where racial retrieval cues were missing. Across Studies 1 and 2, visual attention to racial retrieval cues in photographs documenting historical segregation predicted social justice concept accessibility.

Mortality salience biases attention to positive versus negative images among individuals higher in trait self-control.

Death is inevitable. One way people cope with awareness of death is to focus on the positive things in life. Consistent with this idea, reminders of personal mortality have been found to increase optimism and tune attention towards positive information. The current research tested the hypothesis that persons higher in trait self-control are especially likely to attend to positive (versus negative) stimuli under mortality salience (MS). Participants completed a measure of trait self-control, contemplated their own mortality or a control topic, and then viewed positive and negative affective images while their gaze patterns were recorded. MS increased the attention to positive (versus negative) images among participants higher in trait self-control, whereas those lower in trait self-control exhibited a non-significant trend in the opposite direction. Thus, participants higher in trait self-control showed a positivity bias after contemplating death, which may help explain why they tend to enjoy more positive outcomes in life.

Liking Predicts Judgments of Authenticity in Real-Time Interactions More Robustly Than Personality States or Affect.

We conducted three studies involving small group interactions (N = 622) that examined whether Big Five personality states, affect, and/or liking predict judgments of others' authenticity. Study 1 (n = 119) revealed that neither self-rated personality states nor affect predicted other-rated authenticity. Instead, other-rated liking was the only predictor of other-rated authenticity. Study 2 (n = 281) revealed that other-rated personality states and affect were significant predictors of other-rated authenticity, but other-rated liking was a more important factor in predicting other-rated authenticity than specific behaviors or affect. Based on these results, Study 3 (n = 222) examined whether experimental manipulation of likability had a causal effect on other-ratings of authenticity. Likable actors were indeed judged as more authentic. Together, this suggests that we judge people we like as more authentic and that likability may be more important than the "objective" content of behavior.

Authenticity, Well-Being, and Minority Stress in LGB Individuals: A Scoping Review.

In general (i.e. in heteronormative and cisgendered samples), authenticity appears protective against threats to well-being. Authenticity may also, in part, protect well-being against the minority stressors experienced by sexually minoritized (LGB; lesbian, gay, and bisexual) individuals. In this scoping review, we examined the relation between authenticity and well-being in LGB samples experiencing minority stress. We hypothesized that (i) LGB minority stress relates to decreased authenticity (i.e. inauthenticity), (ii) authenticity relates to increased well-being, and (iii) authenticity influences the relation between LGB minority stress and well-being. We identified 17 studies (N = 4,653) from systematic searches across Medline, ProQuest, PsycINFO, and Scopus using terms related to sexual identity, minority stress, authenticity, and well-being. In almost all studies, proximal (but not distal) stress was associated with inauthenticity, and inauthenticity with decreased well-being. In all but one study, the association between proximal stress and well-being was associated with inauthenticity. Although these results are consistent with our hypotheses, the included studies were limited in scope and heterogenous in their methods, instruments, and samples, restricting conclusions regarding mediation or moderation. The results require replication, well-powered direct comparisons between LGB and non-LGB samples, and consideration of the varied ways authenticity can be conceptualized and measured.

When anger leads to rumination: induction of relative right frontal cortical activity with transcranial direct current stimulation increases anger-related rumination.

Anger is associated with various responses. Research on the neuroscience of anger has revealed that greater left than right frontal cortical activity is associated with angry approach-oriented responses, such as aggression, whereas greater right than left frontal cortical activity is associated with inhibited angry responses mixed with anxiety. In the current research, we extended these past studies by manipulating asymmetric frontal cortical activity using transcranial direct current stimulation and assessing its influence on ruminative responses to an interpersonal insult. Results revealed that self-reported rumination was greatest for participants who received a manipulated increase in relative right frontal cortical activity compared with those who received either a manipulated increase in relative left frontal cortical activity or sham stimulation. Taken together with past findings, the current results suggest that anger associated with greater relative left frontal cortical activity predicts approach-oriented aggressive action, whereas anger associated with greater relative right frontal cortical activity predicts inhibited rumination.

Lashing out after stewing over public insults: the effects of public provocation, provocation intensity, and rumination on triggered displaced aggression.

Four studies present the first evidence showing that public (vs. private) provocation augments triggered displaced aggression by increasing the perceived intensity of the provocation. This effect is shown to be independent of face-saving motivation. Following a public or private provocation, Study 1 participants were induced to ruminate or were distracted for 20 min. They then had an opportunity to aggress against another person who either acted in a neutral or mildly annoying fashion (viz. triggering event). As expected, the magnitude of the greater displaced aggression of those who ruminated before the triggering event compared with those distracted was greater under public than private provocation. Study 2 replicated the findings of Study 1 and confirmed that public provocations are experienced as more intense. Studies 3 and 4 both manipulated provocation intensity directly to show that it mediated the moderating effect of public/private provocation found in Study 1. The greater intensity of a public provocation increases reactivity to a subsequent trigger, which in turn, augments triggered displaced aggression.

Trait nostalgia: Four scales and a recommendation.

We review four established scales for measuring individual differences in trait-level nostalgia: the Nostalgia Inventory, the Southampton Nostalgia Scale, the Nostalgia Prototype Scale, and the Personal Inventory of Nostalgic Experiences. To examine their convergent validity, we re-analyzed data from a published study in which all four scales were administered simultaneously. Multi-group confirmatory factor analyses demonstrated that a one-factor model accurately described the interrelations among the four scales, and supported full metric and partial scalar invariance across U.S. and Chinese samples. When measuring trait nostalgia, we recommend that researchers also consider potential confounders. Specifically, we discuss the importance of controlling for other ways in which individuals habitually reflect on their past, including brooding rumination and upward self-referent counterfactual thinking.

The Role of Positive and Negative Aspects of Life Events in Depressive and Anxiety Symptoms.

Negative or stressful life events are robust risk factors for depression and anxiety. Less attention has been paid to positive aspects of events and whether positivity buffers the impact of negative aspects of events. The present study examined positivity and negativity of interpersonal and non-interpersonal episodic life events in predicting anxiety and depressive symptoms in a sample of 373 young adults. Regressions tested main and interactive effects of positivity and negativity ratings of events in predicting symptom factors (Fears, Anhedonia-Apprehension (AA), General Distress (GD)) relevant to anxiety and depression. A significant interaction demonstrated that positivity protected against high levels of negativity of non-interpersonal events in predicting GD. A main effect of interpersonal negativity predicting higher AA was observed. Results for Fears were non-significant. Findings suggest that positivity of life events may buffer against negativity in predicting symptoms shared between anxiety and depression.