The functional relevance of the lateral prefrontal cortex (lPFC) for the ability to process two tasks simultaneously has been debated extensively in previous studies that employed functional magnetic ...resonance imaging (fMRI) to investigate the neural correlates of dual-task processing. In the present fMRI study, we shed new light on this debate by directly comparing the lPFC activity changes for two cognitive functions commonly associated with dual-task performance: task order control and task set maintenance. We manipulated both functions in a 2 × 2 integrated parametric design. The fMRI data revealed a functional-neuroanatomical dissociation for the lPFC. Regions surrounding the inferior frontal sulcus and the middle frontal gyrus were exclusively associated with task order control but not with increased demands on task set maintenance during dual-task processing. The only lPFC region associated with task set maintenance was located in the left anterior insula. Outside the lPFC, we found dissociable regions for task order control and task set maintenance bilaterally in the premotor cortices with more rostral premotor activity for task order control and more caudal premotor activity for task set maintenance. In addition, task order control activated the intraparietal sulci bilaterally. Our data clearly suggest that task order control is a separable cognitive mechanism in dual-task situations that is related to activity changes in the lPFC and that can be dissociated from task set maintenance.
As a result of demographic changes, physicians are required to deliver needed services with limited resources. Research suggests that tablet PCs with access to patient data may streamline clinical ...workflow. A recent study found tablets with mobile electronic medical records (EMRs) can facilitate data retrieval and produce time savings across the clinical routine within hospital settings. However, the reasons for these time savings, including details on how tablets were being used, remain unclear. The same applies to physicians' perceptions of this tool within an inpatient setting.
This study examined physicians' perception of tablets with EMRs in an inpatient setting. The rationale was to identify both subjective and objective factors that impacted the successful implementation and use of tablets running an EMR.
We developed a 57-item survey questionnaire designed to examine users' perception of and attitude toward tablets, which was administered to 14 participating physicians following 7 weeks of tablet use. Five participants volunteered to participate in a second study that investigated physicians' patterns of tablet use within the EMR environment by digitally tracking and storing usage behavior. Statistical analyses of questionnaire results included mean values with their bootstrapped 95% confidence intervals and multivariate analysis of variance to identify predictors of tablet use.
Physicians reported high degrees of satisfaction with the tablets. There was a general consensus among physicians that tablet use streamlined clinical workflow through optimized data retrieval (rated 0.69, 0.23-1.15 points better than control) and improved communication with patients and other physicians (rated 0.85, 0.54-1.15 and 0.77, 0.38-1.15 points better than control, respectively). Age (F3,11=3.54, P=.04), occupational group (F1,11=7.17, P=.04), and attitude toward novel technologies (F1,11=10.54, P=.02) predicted physicians' satisfaction with the devices and their motivation regarding their further use. Tracking data yielded that only a few of the available functions were used frequently.
Although tablet PCs were consistently perceived as beneficial, several factors contributed to the fact that their full potential was not fully exploited. Training in functionality and providing a reliable infrastructure might foster successful tablet implementation.
Sociodemographic characteristics and depressive symptoms were assessed for their association with increased frequency of intimate partner violence (IPV) victimization since the start of the COVID-19 ...pandemic in a US sample of (N = 1,090) LGBTQ people, using an anonymous online survey. Among those (n = 98) endorsing IPV victimization in their current relationship, more than 18% reported increased frequency since the onset of the pandemic. Respondents in the Southern US, and those with more severe depressive symptoms, were more likely to report an increased frequency of IPV victimization. Providers, researchers, and policymakers should address this prevalent health problem, particularly during public health emergencies.
Brain stimulation is having remarkable impact on clinical neurology. Brain stimulation can modulate neuronal activity in functionally segregated circumscribed regions of the human brain. Polarity, ...frequency, and noise specific stimulation can induce specific manipulations on neural activity. In contrast to neocortical stimulation, deep-brain stimulation has become a tool that can dramatically improve the impact clinicians can possibly have on movement disorders. In contrast, neocortical brain stimulation is proving to be remarkably susceptible to intrinsic brain-states. Although evidence is accumulating that brain stimulation can facilitate recovery processes in patients with cerebral stroke, the high variability of results impedes successful clinical implementation. Interestingly, recent data in healthy subjects suggests that brain-state dependent patterned stimulation might help resolve some of the intrinsic variability found in previous studies. In parallel, other studies suggest that noisy "stochastic resonance" (SR)-like processes are a non-negligible component in non-invasive brain stimulation studies. The hypothesis developed in this manuscript is that stimulation patterning with noisy and oscillatory components will help patients recover from stroke related deficits more reliably. To address this hypothesis we focus on two factors common to both neural computation (intrinsic variables) as well as brain stimulation (extrinsic variables): noise and oscillation. We review diverse theoretical and experimental evidence that demonstrates that subject-function specific brain-states are associated with specific oscillatory activity patterns. These states are transient and can be maintained by noisy processes. The resulting control procedures can resemble homeostatic or SR processes. In this context we try to extend awareness for inter-individual differences and the use of individualized stimulation in the recovery maximization of stroke patients.
Jody C. Culham 1 ,
Stephan A. Brandt 2 , 3 ,
Patrick Cavanagh 1 ,
Nancy G. Kanwisher 4 ,
Anders M. Dale 2 , and
Roger B. H. Tootell 2
1 Department of Psychology, Harvard University, Cambridge, ...Massachusetts 02138; 2 Massachusetts General Hospital Nuclear Magnetic Resonance Center, Charlestown, Massachusetts 02129; 3 Neurologische Klinik, Charité, Humboldt University, Berlin, Germany; and 4 Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
Culham, Jody C., Stephan A. Brandt, Patrick Cavanagh, Nancy G. Kanwisher, Anders M. Dale, and Roger B. H. Tootell. Cortical fMRI activation produced by attentive tracking of moving targets. J. Neurophysiol. 80: 2657-2670, 1998. Attention can be used to keep track of moving items, particularly when there are multiple targets of interest that cannot all be followed with eye movements. Functional magnetic resonance imaging (fMRI) was used to investigate cortical regions involved in attentive tracking. Cortical flattening techniques facilitated within-subject comparisons of activation produced by attentive tracking, visual motion, discrete attention shifts, and eye movements. In the main task, subjects viewed a display of nine green "bouncing balls" and used attention to mentally track a subset of them while fixating. At the start of each attentive-tracking condition, several target balls (e.g., 3/9) turned red for 2 s and then reverted to green. Subjects then used attention to keep track of the previously indicated targets, which were otherwise indistinguishable from the nontargets. Attentive-tracking conditions alternated with passive viewing of the same display when no targets had been indicated. Subjects were pretested with an eye-movement monitor to ensure they could perform the task accurately while fixating. For seven subjects, functional activation was superimposed on each individual's cortically unfolded surface. Comparisons between attentive tracking and passive viewing revealed bilateral activation in parietal cortex (intraparietal sulcus, postcentral sulcus, superior parietal lobule, and precuneus), frontal cortex (frontal eye fields and precentral sulcus), and the MT complex (including motion-selective areas MT and MST). Attentional enhancement was absent in early visual areas and weak in the MT complex. However, in parietal and frontal areas, the signal change produced by the moving stimuli was more than doubled when items were tracked attentively. Comparisons between attentive tracking and attention shifting revealed essentially identical activation patterns that differed only in the magnitude of activation. This suggests that parietal cortex is involved not only in discrete shifts of attention between objects at different spatial locations but also in continuous "attentional pursuit" of moving objects. Attentive-tracking activation patterns were also similar, though not identical, to those produced by eye movements. Taken together, these results suggest that attentive tracking is mediated by a network of areas that includes parietal and frontal regions responsible for attention shifts and eye movements and the MT complex, thought to be responsible for motion perception. These results are consistent with theoretical models of attentive tracking as an attentional process that assigns spatial tags to targets and registers changes in their position, generating a high-level percept of apparent motion.
Consensual nonmonogamous (CNM) relationships (e.g., open relationships) and identities (e.g., polyamorous) are becoming increasingly common, including among lesbian, gay, bisexual, transgender, and ...queer (LGBTQ+) people. However, few studies have examined stigma related to CNM relationships and identities (i.e., CNM-related stigma) in the general population, and even less in LGBTQ+ populations. Additionally, existing studies of CNM-related stigma often do not distinguish between different forms of stigma (e.g., enacted vs. anticipated). To address this gap in the literature, this study sought to examine (a) sociodemographic differences in enacted and anticipated CNM-related stigma and (b) the association between enacted and anticipated stigma among a sample of (N = 1,000) LGBTQ+ people. Using data from a cross-sectional, Internet-based survey, we observed sociodemographic differences in enacted CNM-related stigma by generation status, gender identity, employment, current relationship, and parental status. Differences in anticipated stigma were observed by age, sexual identity, education, CNM identity, current relationship, and marital status. Our findings also reveal a strong association between enacted and anticipated CNM-related stigma. Taken together, these findings suggest that both forms of stigma are commonly experienced among LGBTQ+ people, and that certain LGBTQ+ subgroups may be at heightened risk for such experiences. Indeed, LGBTQ+ subgroups with less social privilege (e.g., people with disabilities) may be particularly vulnerable to CNM-related stigma. It is imperative that health care providers facilitate open and nonjudgmental discussions about relationship diversity and experiences of CNM-related stigma with their LGBTQ+ patients. Additional research in this area is also warranted, given the limitations of the extant literature.
Public Significance Statement
There is little research regarding the stigma experienced by LGBTQ+ people who are engaged in consensual nonmonogamous (CNM) relationships and/or who identify as CNM. The current study found that anticipated CNM-related stigma affects LGBTQ+ individuals in relation to the intersection of other identities, such as age, sexual identity, and current relationship status, among others. Also, a strong association between enacted and anticipated CNM-related stigma was also found.
Abstract Introduction Repetitive transorbital alternating current stimulation (rtACS) can improve visual deficits in patients with optic nerve damage. Recent retrospective results suggest that rtACS ...enhances oscillatory brain activity. The exact mechanisms of rtACS are unclear and little is known about possibly frequency-specific neural-plastic mechanisms. An association between bandwidth-confined neural-entrainment and vision recovery maximization could offer a novel therapeutic option for patients with optic neuropathy. Objectives The goal of this prospective open-label study was to investigate if the enhancement of rhythmic brain activity over 10 days of consecutive rtACS stimulation is associated with visual field recovery. The secondary goal was to investigate neurophysiological mechanisms related to frequency dependent adaptive plasticity. Methods 18 Patients with visual field impairments resulting from pre-chiasmatic partial optic nerve damage received rtACS on 10 consecutive days. Daily, subject-specific treatment parameters (<500 μA, 9–37 Hz, 25–40 min/day) were defined and EEG-spectra collected prior to and after rtACS. Visual field data was collected at day 1 and 10. The change of spectral-power in classic bandwidths were investigated and correlated with visual field deficit recovery. Results After 10 days of rtACS alpha-power over bilateral occipital electrodes was significantly larger than at baseline ( FTime x alpha-power p < 0.01). This effect was progressive over subsequent days of stimulation (cubic-fit, R2 0.70, RMSE 0.008). Perimetric results improved significantly, but they were not associated with changes in alpha-synchronization. Discussion rtACS can induce cumulative bandwidth-confined changes in brain rhythms over multiple sessions. These findings are in line with the notion of brain-state dependent 1 and bandwidth-confined entrainment 2 as well as rtACS facilitated visual recovery 3.
In the last decade, combined transcranial magnetic stimulation (TMS)-neuroimaging studies have greatly stimulated research in the field of TMS and neuroimaging. Here, we review how TMS can be ...combined with various neuroimaging techniques to investigate human brain function. When applied during neuroimaging (online approach), TMS can be used to test how focal cortex stimulation acutely modifies the activity and connectivity in the stimulated neuronal circuits. TMS and neuroimaging can also be separated in time (offline approach). A conditioning session of repetitive TMS (rTMS) may be used to induce rapid reorganization in functional brain networks. The temporospatial patterns of TMS-induced reorganization can be subsequently mapped by using neuroimaging methods. Alternatively, neuroimaging may be performed first to localize brain areas that are involved in a given task. The temporospatial information obtained by neuroimaging can be used to define the optimal site and time point of stimulation in a subsequent experiment in which TMS is used to probe the functional contribution of the stimulated area to a specific task. In this review, we first address some general methodologic issues that need to be taken into account when using TMS in the context of neuroimaging. We then discuss the use of specific brain mapping techniques in conjunction with TMS. We emphasize that the various neuroimaging techniques offer complementary information and have different methodologic strengths and weaknesses.
Early visual areas (V1, V2, V3/VP, V4v) contain representations of the contralateral hemifield within each hemisphere. Little is known about the role of the visual hemifields along the visuo‐spatial ...attention processing hierarchy. It is hypothesized that attentional information processing is more efficient across the hemifields (known as bilateral field advantage) and that the integration of information is greater within one hemifield as compared with across the hemifields. Using functional magnetic resonance imaging we examined the effect of distance and hemifield on parallel attentional processing in the early visual areas (V1–V4v) at individually mapped retinotopic locations aligned adjacently or separately within or across the hemifields. We found that the bilateral field advantage in parallel attentional processing over separated attended locations can be assigned, at least partly, to differences in distractor position integration in early visual areas. These results provide evidence for a greater integration of locations between two attended locations within one hemifield than across both hemifields. This nicely correlates with behavioral findings of a bilateral field advantage in parallel attentional processing (when distractors in between cannot be excluded) and a unilateral field advantage if attention has to be shifted across separated locations (when locations in between were integrated).
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