The interaction of respiration and visual feedback on the control of force and neural activation of the agonist muscle

The purpose of this study was to compare force variability and the neural activation of the agonist muscle during constant isometric contractions at different force levels when the amplitude of respiration and visual feedback were varied. Twenty young adults (20–32 years, 10 men and 10 women) were instructed to accurately match a target force at 15% and 50% of their maximal voluntary contraction (MVC) with abduction of the index finger while controlling their respiration at different amplitudes (85%, 100% and 125% normal) in the presence and absence of visual feedback. Each trial lasted 22 s and visual feedback was removed from 8–12 and 16–20 s. Each subject performed three trials with each respiratory condition at each force level. Force variability was quantified as the standard deviation of the detrended force data. The neural activation of the first dorsal interosseus (FDI) was measured with bipolar surface electrodes placed distal to the innervation zone. Relative to normal respiration, force variability increased significantly only during high-amplitude respiration (∼63%). The increase in force variability from normal- to high-amplitude respiration was strongly associated with amplified force oscillations from 0 to 3 Hz (R² ranged from .68 to .84, p < .001). Furthermore, the increase in force variability was exacerbated in the presence of visual feedback at 50% MVC (vision vs. no-vision: .97 vs. .87 N) and was strongly associated with amplified force oscillations from 0 to 1 Hz (R² = .82) and weakly associated with greater power from 12 to 30 Hz (R² = .24) in the EMG of the agonist muscle. Our findings demonstrate that high-amplitude respiration and visual feedback of force interact and amplify force variability in young adults during moderate levels of effort.     

Assessing crossmodal matching of abstract auditory and visual stimuli in posterior superior temporal sulcus with MEG

Associating crossmodal auditory and visual stimuli is an important component of perception, with the posterior superior temporal sulcus (pSTS) hypothesized to support this. However, recent evidence has argued that the pSTS serves to associate two stimuli irrespective of modality. To examine the contribution of pSTS to crossmodal recognition, participants (N = 13) learned 12 abstract, non-linguistic pairs of stimuli over 3 weeks. These paired associates comprised four types: auditory–visual (AV), auditory–auditory (AA), visual–auditory (VA), and visual–visual (VV). At week four, participants were scanned using magnetoencephalography (MEG) while performing a correct/incorrect judgment on pairs of items. Using an implementation of synthetic aperture magnetometry that computes real statistics across trials (SAMspm), we directly contrasted crossmodal (AV and VA) with unimodal (AA and VV) pairs from stimulus-onset to 2 s in theta (4–8 Hz), alpha (9–15 Hz), beta (16–30 Hz), and gamma (31–50 Hz) frequencies. We found pSTS showed greater desynchronization in the beta frequency for crossmodal compared with unimodal trials, suggesting greater activity during the crossmodal pairs, which was not influenced by congruency of the paired stimuli. Using a sliding window SAM analysis, we found the timing of this difference began in a window from 250 to 750 ms after stimulus-onset. Further, when we directly contrasted all sub-types of paired associates from stimulus-onset to 2 s, we found that pSTS seemed to respond to dynamic, auditory stimuli, rather than crossmodal stimuli per se. These findings support an early role for pSTS in the processing of dynamic, auditory stimuli, and do not support claims that pSTS is responsible for associating two stimuli irrespective of their modality.     

Convergence between measures of work-to-family and family-to-work conflict: A meta-analytic examination

The overlap between measures of work-to-family (WFC) and family-to-work conflict (FWC) was meta-analytically investigated. Researchers have assumed WFC and FWC to be distinct, however, this assumption requires empirical verification. Across 25 independent samples (total N = 9079) the sample size weighted mean observed correlation was .38 and the reliability corrected correlation was .48. The pattern of external correlates for the two types of conflict was also examined. Both forms of conflict had similar (.41) reliability corrected correlations with measures of organizational withdrawal. WFC conflict correlated .41 (k =  15, N = 4714) with job stressors and .17 (k = 13, N = 3312) with non-work stressors whereas FWC conflict correlated .27 with job stressors and .23 with non-work stressors. Correlations between the two forms of work/family conflict and other variables such as organizational commitment, job and life satisfaction, and health were examined. Implications for the discriminant validity of the two types of conflict measures are discussed.     

The N400 effect in children: relationships with comprehension, vocabulary and decoding

Using event-related potentials (ERPs), we investigated the N400 (an ERP component that occurs in response to meaningful stimuli) in children aged 8-10 years old and examined relationships between the N400 and individual differences in listening comprehension, word recognition and non-word decoding. Moreover, we tested the claim that the N400 effect provides a valuable indicator of behavioural vocabulary knowledge. Eighteen children were presented with picture-word pairs that were either ‘congruent’ (the picture depicted the spoken word) or ‘incongruent’ (they were unrelated). Three peaks were observed in the ERP waveform triggered to the onset of the picture-word stimuli: an N100 in fronto-central channels, an N200 in central-parietal channels and an N400 in frontal, central and parietal channels. In contrast to the N100 peak, the N200 and N400 peaks were sensitive to semantic incongruency with greater peak amplitudes for incongruent than congruent conditions. The incongruency effects for each peak correlated positively with listening comprehension but when the peak amplitudes were averaged across congruent/incongruent conditions they correlated positively with non-word decoding. These findings provide neurophysiological support for the position that sensitivity to semantic context (reflected in the N400 effect) is crucial for comprehension whereas phonological decoding skill relates to more general processing differences reflected in the ERP waveform. There were no correlations between ERP and behavioural measures of expressive or receptive vocabulary knowledge for the same items, suggesting that the N400 effect may not be a reliable estimate of vocabulary knowledge in children aged 8-10 years.     

Social support and work–family conflict: A test of an indirect effects model

Most work–family research on social support is based on matching domain relationships, that is, social support in the work domain is related to work interfering with family conflict (WIF) and social support in the family domain is related to family interfering with work conflict (FIW). In this research, based on the conservation of resources (COR) model, we examined the cross domain indirect relationship between social support in the work domain and FIW and the cross domain indirect relationship between social support in the family domain and WIF. We tested this model across three samples in two studies. In Study 1, we examined the cross domain influence of supervisory and spouse support on work–family conflict using two large random samples (N = 1130; N = 2769). In Study 2, we tested an expanded model of social support to include both generic and work–family specific support, and examined the cross domain indirect relationships between these two types of support on work–family conflict using a sample of 435 employees. Specifically, we proposed that social support systems in the work domain such as family friendly organizational policies, family supportive organizational climate, perceived organizational support, and perceived supervisory support will be indirectly and negatively related to FIW via WIF and that spouse/partner support will be indirectly and negatively related to WIF via FIW. Results for Study 1 provided support for the cross domain indirect effects model and results for Study 2 provided support for the cross domain indirect effects for work–family specific social support systems. We discuss implications of these results for the theory and practice of managing work–family conflict.     

The consistency and structure of aspect-based career preferences

Career aspects (e.g., work environment, using verbal ability, length of training, teamwork) are an elaboration and extension of vocational interests. Aspect-based preferences can serve individuals and their career counselors only if they are reliable and stable. Study 1 estimated the two-week test–retest reliability of 213 college freshmen's preferences in 31 career aspects and the two-year stability of these preferences for 132 of these freshmen. The two-week reliability and the two-year stability of both the within-aspect preferred levels (e.g., “only indoors” most preferred, but “mostly indoors” is also acceptable) and the aspect importance were tested for each of the aspects. The interquartile ranges of the two-week reliability of the aspect importance and of the preferred within-aspect levels were .54–.62 and .63–.74 for the 31 aspects; the interquartile ranges of the two-year stabilities were .38–.48 and .48–.59, respectively. These interquartile ranges reflect the variance in consistency among the aspects. Study 2 explored the structure of the aspects based on the pattern of associations among them. In addition, it examined the consistency of the aspect structures by comparing them in four samples (total N = 40,313). The structure was found consistent across time (Spearman r_s = .88, .76 and .68, two weeks, two years, and 20 years later, respectively), within culture (r_s = .75 and .76, for women and men, respectively), and across cultures (USA and Israel; r_s = .64). Theoretical and practical implications are discussed.     

Working while studying at university: The relationship between work benefits and demands and engagement and well-being

We tested a role-conflict, depletion, and enrichment model, in which work-based benefits (enabling resources, psychological rewards, and psychological involvement) and work-based demands (time-, strain-, and behaviour-based demands, and hours worked) were antecedents to work–university conflict and work–university facilitation, which, in turn, were antecedent to students' academic engagement (dedication and vigour) and well-being (general and context-specific feelings about university). We also tested whether conflict and facilitation acted as mediators in the relationships between benefits and demands and the outcomes of engagement and well-being. The hypotheses were tested using 185 university students (77% female; mean age = 22.7 years) who were working while studying. Work-based benefits (enabling resources, rewards, and involvement) were associated with higher work–university facilitation; more time demands and fewer psychological rewards were associated with more work–university conflict; facilitation was associated with more engagement (dedication) and general well-being; and conflict was associated with more negative feelings towards the university. There were no mediation effects. Working while studying is related to students' engagement and well-being, although modest effects were explained by role-conflict theory.     

Gamma- and theta-band synchronization during semantic priming reflect local and long-range lexical–semantic networks

Anterior and posterior brain areas are involved in the storage and retrieval of semantic representations, but it is not known how these areas dynamically interact during semantic processing. We hypothesized that long-range theta-band coherence would reflect coupling of these areas and examined the oscillatory dynamics of lexical–semantic processing using a semantic priming paradigm with a delayed letter-search task while recording subjects’ EEG. Time–frequency analysis revealed facilitation of semantic processing for Related compared to Unrelated conditions, which resulted in a reduced N400 and reduced gamma power from 150 to 450 ms. Moreover, we observed greater anterior–posterior theta coherence for Unrelated compared to Related conditions over the time windows 150–425 ms and 600–900 ms. We suggest that while gamma power reflects activation of local functional networks supporting semantic representations, theta coherence indicates dynamic coupling of anterior and posterior areas for retrieval and post-retrieval processing and possibly an interaction between semantic relatedness and working memory.     

Black–White mean differences in job satisfaction: A meta-analysis

Studies examining Black–White mean differences in job satisfaction have provided little clarity regarding whether there are meaningful differences between the two racial/ethnic groups on this job attitude. The present study sought to reconcile prior inconsistent findings via a meta-analytic synthesis of this literature (N = 753,791; K = 63 independent samples from 55 studies) and examined whether moderators explained the observed variability in effects. Using Hedges and Vevea's (1998) random-effects meta-analytic approach, we found that, on average, White workers were slightly more satisfied with their jobs than Black workers (g_corrected = .09; 95% credibility interval = −.21 to .39) and this effect was larger in more nationally representative samples (g_corrected = .24). The substantial true variability around this effect suggests the presence of moderators and the need for caution in interpreting the overall effect as it likely does not generalize across all work settings. Data collection year, geographic location within the U.S., job sector, and measure type were not found to moderate Black–White mean differences in job satisfaction. However, job complexity and sample demographic composition did significantly moderate this relationship. Our results show that the magnitude and direction of Black–White mean differences in job satisfaction are influenced by the context.     

The effect of gender on the N1-P2 auditory complex while listening and speaking with altered auditory feedback

The effect of gender on the N1-P2 auditory complex was examined while listening and speaking with altered auditory feedback. Fifteen normal hearing adult males and 15 females participated. N1-P2 components were evoked while listening to self-produced nonaltered and frequency shifted /a/ tokens and during production of /a/ tokens during nonaltered auditory feedback (NAF), frequency altered feedback (FAF), and delayed auditory feedback (DAF; 50 and 200 ms). During speech production, females exhibited earlier N1 latencies during 50 ms DAF and earlier P2 latencies during 50 ms DAF and FAF. There were no significant differences in N1-P2 amplitudes across all conditions. Comparing listening to active speaking, N1 and P2 latencies were earlier among females, with speaking, and under NAF. N1-P2 amplitudes were significantly reduced during speech production. These findings are consistent with the notions that speech production suppresses auditory cortex responsiveness and males and females process altered auditory feedback differently while speaking.     

Clarifying relationships among work and family social support, stressors, and work-family conflict

Although work and family social support predict role stressors and work-family conflict, there has been much ambiguity regarding the conceptual relationships among these constructs. Using path analysis on meta-analytically derived validity coefficients (528 effect sizes from 156 samples), we compare three models to address these concerns and clarify relationships. Results revealed that social support, controlling for role involvement, is best viewed as an antecedent of role stressors and subsequent work-family conflict. Controlling for work and family involvement, work and family social support were most related to same domain role conflict (β = −.46, p < .05; β = −.43, p < .05) and role ambiguity (β = −.28, p < .05; β = −.33, p < .05). Subsequently, work role conflict and time demands were most related to work-to-family conflict (β = .39, p < .05; β = .21, p < .05), while family role conflict and role ambiguity were most related to family-to-work conflict (β = .22, p < .05; β = .24, p < .05). Implications for research and practice, along with suggestions for theoretical advances, are discussed.     

Electrophysiological correlates of anterior cingulate function in a go/no-go task: Effects of response conflict and trial type frequency

Neuroimaging and computational modeling studies have led to the suggestion that response conflict monitoring by the anterior cingulate cortex plays a key role in cognitive control. For example, response conflict is high when a response must be withheld (no-go) in contexts in which there is a prepotent tendency to make an overt (go) response. An event-related brain potential (ERP) component, the N2, is more pronounced on no-go than on go trials and was previously thought to reflect the need to inhibit the go response. However, the N2 may instead reflect the high degree of response conflict on no-go trials. If so, an N2 should also be apparent when subjects make a go response in conditions in which nogo events are more common. To test this hypothesis, we collected high-density ERP data from subjects performing a go/no-go task, in which the relative frequency of go versus no-go stimuli was varied. Consistent with our hypothesis, an N2 was apparent on both go and no-go trials and showed the properties expected of an ERP measure of conflict detection on correct trials: (1) It was enhanced for low-frequency stimuli, irrespective of whether these stimuli were associated with generating or suppressing a response, and (2) it was localized to the anterior cingulate cortex. This suggests that previous conceptions of the no-go N2 as indexing response inhibition may be in need of revision. Instead, the results are consistent with the view that the N2 in go/no-go tasks reflects conflict arising from competition between the execution and the inhibition of a single response.     

Heart rate variability and drawing impairment in hypoxemic COPD

We studied 54 patients with hypoxemic chronic obstructive pulmonary disease (COPD). The Mini Mental State Examination and the Mental Deterioration Battery were used for neuropsychological assessment. Heart rate variability (HRV) was assessed based on 24-h Holter ECG recording. Mann–Whitney test was used to compare HRV parameters of patients performing normally or abnormally on individual neuropsychological tasks. Spearman’s rho was used to investigate the correlations between HRV parameters and neuropsychological scores, indexes of health status or COPD severity. Patients with defective performance at copying drawings with landmarks (CDL) test (N = 23) had lower very low frequency (VLF) power with respect to patients with normal performance (N = 31) (24 h: median 213; interquartile range 120–282 vs. 309; 188–431 ms², p = 0.043; daytime: 202; 111–292 vs. 342; 194–397 ms², p = 0.039). The CDL score correlated with the VLF power (24 h: ρ = 0.27, p = 0.049; daytime: ρ = 0.30, p = 0.028), and the normalized low frequency/high frequency (LF/HF) ratio (24 h: ρ = 0.27, p = 0.05; daytime: ρ = 0.33, p = 0.015). Sympathetic modulation decreased for increasing severity of COPD. In conclusion, drawing impairment correlates with depressed sympathetic modulation in patients with COPD, and both might be indexes of COPD severity.     

Factor structure of the Brief Psychiatric Rating Scale for Children (BPRS-C) among Hospital Patients and Community Clients

The factor structure, reliability and concurrent validity of the Brief Psychiatric Rating Scale for Children (BPRS-C) was examined. The BPRS-C was designed to measure child psychopathology with seven scales consisting of three items each. Two large samples of intake assessments at admission to the public mental health system of state psychiatric hospitals (n = 6712) and community mental health centers (n = 21,459) for children aged 3–17 were examined. In both samples exploratory and confirmatory factor analysis found seven factors that generally supported the BPRS-C seven scale structure. Reliability as measured by internal consistency was acceptable with an average alpha of .72 (SD = .09). Mean scale scores across diagnoses and concurrent correlations with the Child Behavior Checklist (CBCL) were consistent with expectations.     

Auditory instructional cues benefit unimanual and bimanual drawing in Parkinson's disease patients

The present study investigated performance of unimanual and bimanual anti-phase and in-phase upper limb line drawing using three different types of cues. Fifteen Parkinson’s disease (PD) patients, 15 elderly, and 15 young adults drew lines away from and towards their body on a tabletop every 1000 ms for 30 s under three different cueing conditions: (1) verbal (‘up’, ‘down’); (2) auditory (high tone, low tone); (3) visual (target line switched from top to bottom). PD patients had larger and more variable amplitudes which may be related to the finding that they also produced more curvilinear movements than young and elderly adults. Consistent with previous research, when compared to the elderly and young adult group PD patients produced a mean relative phase which deviated more from the instructed coordination modes and they showed larger variability of relative phase in bimanual coordination, especially in anti-phase conditions. For all groups, auditory and verbal cues resulted in lower coefficient of variance of cycle time, lower variability of amplitude and lower variability of relative phase than visual cues. The benefit of auditory cues may be related to the timing nature of the task or factors related to the auditory cues (e.g., reduced attentional demands, more kinesthetic focus).     

Understanding action language modulates oscillatory mu and beta rhythms in the same way as observing actions

The mu rhythms (8–13 Hz) and the beta rhythms (15 up to 30 Hz) of the EEG are observed in the central electrodes (C3, Cz and C4) in resting states, and become suppressed when participants perform a manual action or when they observe another’s action. This has led researchers to consider that these rhythms are electrophysiological markers of the motor neuron activity in humans. This study tested whether the comprehension of action language, unlike abstract language, modulates mu and low beta rhythms (15–20 Hz) in a similar way as the observation of real actions. The log-ratios were calculated for each oscillatory band between each condition and baseline resting periods. The results indicated that both action language and action videos caused mu and beta suppression (negative log-ratios), whereas abstract language did not, confirming the hypothesis that understanding action language activates motor networks in the brain. In other words, the resonance of motor areas associated with action language is compatible with the embodiment approach to linguistic meaning.     

State mood,task performance,and behavior at work: A within-persons approach

We examine the intra-individual relationships between state mood and the primary components of the individual-level criterion space (task performance, organizational citizenship behavior, and work withdrawal) as they vary within the stream of work. Using experience-sampling methods, 67 individuals in a call center responded to surveys on palmtop computers at random intervals 4–5 times each day for 3 weeks (total N = 2329). These data were matched to objective task performance obtained from organizational call records (total N = 1191). Within-persons, periods of positive mood were associated with periods of improved task performance (as evidenced by shorter call time) and engaging in work withdrawal. Trait meta-mood moderated these relationships. Specifically, individuals who attended to their moods had a stronger relationship between mood and speed of task performance (call time) and individuals able to repair their mood cognitively evidenced a weaker relationship between mood and withdrawal. Implications and the use of within-persons designs are discussed.     

Combined Medication and CBT for Generalized Anxiety Disorder With African American Participants: Reliability and Validity of Assessments and Preliminary Outcomes

Using data from a study of combined cognitive behavioral therapy (CBT) and venlafaxine XR in the treatment of generalized anxiety disorder (GAD), the current article examines the reliability and convergent validity of scales, and preliminary outcomes, for African American compared with European American patients. Internal consistency and short-term stability coefficients for African Americans (n = 42) were adequate and similar or higher compared with those found for European Americans (n = 164) for standard scales used in GAD treatment research. Correlations among outcome measures among African Americans were in general not significantly different for African Americans compared with European Americans. A subset of patients with DSM-IV–diagnosed GAD (n = 24 African Americans; n = 52 European Americans) were randomly selected to be offered the option of adding 12 sessions of CBT to venlafaxine XR treatment. Of those offered CBT, 33.3% (n = 8) of the African Americans and 32.6% (n = 17) of the European Americans accepted and attended at least one CBT treatment session. The outcomes for African Americans receiving combined treatment were not significantly different from European Americans receiving combined treatment on primary or secondary efficacy measures.     

Distributed attentional deficits in chronic methamphetamine abusers: evidence from the Attentional Network Task (ANT)

Objective

The goal of the present study was to examine distributed attentional functions in long-term but currently abstinent methamphetamine (MA) abusers using a task that measures attentional alertness, orienting, and conflict resolution.

Methods

Thirty currently abstinent MA abusers (1 month-5 years) and 22 healthy non-substance using adults were administered a multimodal version of the Attentional Network Task (ANT-I). In this task subjects identified the direction of a centrally presented arrow using a key press. Analyses examined the interaction between alerting tones, location cueing and congruency between the target arrows and flanking distractor stimuli.

Results

All participants were faster when an auditory tone preceded the trial onset (p < 0.001), on trials in which a valid cue preceded the location of the target arrow (p < 0.001), and on congruent trials (i.e., when all display arrows faced in the same direction) (p < 0.001). Of primary interest was the finding that MA abusers were more influenced by the conflict between the peripheral arrows and the central target arrow (p = 0.009). There were also correlations between length of drug sobriety and executive function as well as between drug-induced psychiatric symptoms and alertness.

Conclusions

These results suggest that chronic MA abusers display cognitive deficits that may reflect a specific vulnerability to distraction on a task of executive function. These findings are consistent with other studies that have reported deficits in anterior attentional systems and top-down cognitive control.     

Magnitude and chronometry of neural mechanisms of emotion regulation in subtypes of aggressive children

Emotion regulation is a key social skill and children who fail to master it are at risk for clinical disorders. Specific styles of emotion regulation have been associated with particular patterns of prefrontal activation. We investigated whether anxious aggressive children would reveal a different pattern of cortical activation than non-anxious aggressive children and normally-developing children. We examined the magnitude and timing of source activation underlying the N2—an ERP associated with inhibitory control—during a go/nogo task with a negative emotion induction component (loss of earned points). We estimated cortical activation for two regions of interest—a ventral prefrontal and a dorsomedial prefrontal region—for three 100-ms windows over the range of the N2 (200–500 ms). Anxious aggressive children showed high ventral prefrontal activation in the early window; non-anxious aggressive children showed high ventral prefrontal activation in the late window, but only for the duration of the emotion induction; and normally-developing children showed low ventral prefrontal activation throughout. There were no group differences in dorsomedial prefrontal activation. These results suggest that anxious aggressive children recruit ventral prefrontal activation quickly and indiscriminately, possibly giving rise to their rigid, threat-oriented approach to conflict. The late ventral prefrontal activation seen for non-anxious aggressive children may underlie a more delayed, situation-specific, but ineffective response to frustration.