An epigenetic barrier sets the timing of human neuronal maturation.

The pace of human brain development is highly protracted compared with most other species1-7. The maturation of cortical neurons is particularly slow, taking months to years to develop adult functions3-5. Remarkably, such protracted timing is retained in cortical neurons derived from human pluripotent stem cells (hPSCs) during in vitro differentiation or upon transplantation into the mouse brain4,8,9. Those findings suggest the presence of a cell-intrinsic clock setting the pace of neuronal maturation, although the molecular nature of this clock remains unknown. Here we identify an epigenetic developmental programme that sets the timing of human neuronal maturation. First, we developed a hPSC-based approach to synchronize the birth of cortical neurons in vitro which enabled us to define an atlas of morphological, functional and molecular maturation. We observed a slow unfolding of maturation programmes, limited by the retention of specific epigenetic factors. Loss of function of several of those factors in cortical neurons enables precocious maturation. Transient inhibition of EZH2, EHMT1 and EHMT2 or DOT1L, at progenitor stage primes newly born neurons to rapidly acquire mature properties upon differentiation. Thus our findings reveal that the rate at which human neurons mature is set well before neurogenesis through the establishment of an epigenetic barrier in progenitor cells. Mechanistically, this barrier holds transcriptional maturation programmes in a poised state that is gradually released to ensure the prolonged timeline of human cortical neuron maturation.

Home-administered transcranial direct current stimulation is a feasible intervention for depression: an observational cohort study.

Transcranial direct current stimulation (tDCS) is an emerging treatment for major depression. We recruited participants with moderate-to-severe major depressive episodes for an observational clinical trial using Soterix Medical's tDCS telehealth platform as a standard of care. The acute intervention consisted of 28 sessions (5 sessions/week, 6 weeks) of the left anodal dorsolateral prefrontal cortex (DLPFC) tDCS (2.0 mA × 30 min) followed by a tapering phase of weekly sessions for 4 weeks (weeks 7-10). The n = 16 completing participants had a significant reduction in depressive symptoms by week 2 of treatment [Montgomery-Åsberg Depression Rating Scale (MADRS), Baseline: 28.00 ± 4.35 vs. Week 2: 17.12 ± 5.32, p < 0.001] with continual improvement across each biweekly timepoint. Acute intervention responder and remission rates were 75 and 63% and 88 and 81% following the taper period (week 10).

Immediate and Differential Response to Emotional Stimuli Associated With Transcranial Direct Current Stimulation for Depression: A Visual-Search Task Pilot Study.

OBJECTIVES: When administered in repeated daily doses, transcranial direct current stimulation (tDCS) directed to the prefrontal cortex has cumulative efficacy for the treatment of depression. Depression can be marked by altered processing of emotionally salient information. An acute marker of response to tDCS may be measured as an immediate change in emotional information processing. Using an easily administered web-based task, we tested immediate changes in emotional information processing in acute response to tDCS in participants with and without depression. MATERIALS AND METHODS: We enrolled n = 21 women with mild-to-moderate depression and n = 20 controls without depression to complete a web-based visual search task before and after 30 minutes of tDCS directed to the prefrontal cortex. The timed task required participants to identify a target face among arrays showing sad, neutral, or mixed (distractor) expressions. RESULTS: At baseline, as predicted, the participants with depression differed from those without in emotional processing speed (mean z score difference -0.66 ± 0.27, p = 0.022) and accuracy in identifying sad stimuli (error rate: 4.4% vs 1.8%, p = 0.039). In response to tDCS, the participants with depression became significantly faster on the distractor condition (pre- vs post-tDCS z scores: -0.45 ± 0.65 vs -0.85 ± 0.65, p = 0.009), suggesting a specific reduction in bias toward negative emotional information. In response to tDCS, the depressed group also had significant improvements in self-reported mood (increased happy, decreased sad and anxious mood). CONCLUSIONS: Participants with depression vs those without were differentiated by their performance of the visual search task at baseline and in response to tDCS. Given that measurable effects on depression scales may require weeks of tDCS treatments, acute change in emotional information processing can serve as an easily obtainable marker of depression and its response to tDCS. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT05188248.

Dynamic network-guided CRISPRi screen identifies CTCF-loop-constrained nonlinear enhancer gene regulatory activity during cell state transitions.

Comprehensive enhancer discovery is challenging because most enhancers, especially those contributing to complex diseases, have weak effects on gene expression. Our gene regulatory network modeling identified that nonlinear enhancer gene regulation during cell state transitions can be leveraged to improve the sensitivity of enhancer discovery. Using human embryonic stem cell definitive endoderm differentiation as a dynamic transition system, we conducted a mid-transition CRISPRi-based enhancer screen. We discovered a comprehensive set of enhancers for each of the core endoderm-specifying transcription factors. Many enhancers had strong effects mid-transition but weak effects post-transition, consistent with the nonlinear temporal responses to enhancer perturbation predicted by the modeling. Integrating three-dimensional genomic information, we were able to develop a CTCF-loop-constrained Interaction Activity model that can better predict functional enhancers compared to models that rely on Hi-C-based enhancer-promoter contact frequency. Our study provides generalizable strategies for sensitive and systematic enhancer discovery in both normal and pathological cell state transitions.

Moving intra-individual variability (IIV) towards clinical utility: IIV measured using a commercial testing platform.

OBJECTIVES: Intra-individual variability (IIV), measured across repeated response times (RT) during continuous psychomotor tasks, is an early marker of cognitive change in the context of neurodegeneration. To advance IIV towards broader application in clinical research, we evaluated IIV from a commercial cognitive testing platform and compared it to the calculation approaches used in experimental cognitive studies. METHODS: Cognitive assessment was administered in participants with multiple sclerosis (MS) during the baseline of an unrelated study. Cogstate was used for computer-based measures providing three timed-trial tasks measuring simple (Detection; DET) and choice (Identification; IDN) RT and working memory (One-Back; ONB). IIV for each task was automatically output by the program (calculated as a log10-transformed standard deviation or "LSD"). We calculated IIV from the raw RTs using coefficient of variation (CoV), regression-based, and ex-Gaussian methods. The IIV from each calculation was then compared by rank across participants. RESULTS: A total of n = 120 participants with MS aged 20-72 (Mean ± SD, 48.99 ± 12.09) completed the baseline cognitive measures. For each task, the interclass correlation coefficient was generated. Each ICC showed that LSD, CoV, ex-Gaussian, and regression methods clustered strongly (Average ICC for DET: 0.95 with 95% CI [0.93, 0.96]; Average ICC for IDN: 0.92 with 95% CI [0.88 to 0.93]; Average ICC for ONB: 0.93 with 95% CI [0.90 to 0.94]). Correlational analyses indicated the strongest correlation between LSD and CoV for all tasks (rs ≥ 0.94). CONCLUSION: The LSD was consistent with research-based methods for IIV calculations. These findings support the use of LSD for the future measurement of IIV for clinical studies.

Effects of attention bias modification for anxiety: Neurophysiological indices and moderation by symptom severity.

OBJECTIVE: Attention bias modification (ABM) aims to decrease anxiety symptom severity through the reduction of threat-related attention bias (AB). Individual differences in treatment response and poor measurement reliability of AB have called its clinical promise into question. The current study examined whether individual differences in anxiety severity at baseline moderated treatment response, and employed both behavioral and neurophysiological metrics of AB. METHODS: Participants (N = 99) were randomly assigned to four weeks of ABM or placebo control training (PT). Self-reported anxiety symptom severity, and AB metrics and ERPs generated during the dot probe task were collected at baseline (Time 1), one-week post-intervention (Time 5), and at a three-month follow-up (Time 6). RESULTS: ABM, relative to PT, reduced ERPs indexing attention discrimination (N170) and increased ERPs indexing salience tracking (P3). Increases in P3 were associated with ABM-related reductions in anxiety. Anxiety severity was reduced following ABM, but only among those with higher baseline anxiety symptom severity. CONCLUSIONS: ABM effectively reduced symptom severity among those with higher levels of anxiety, and modulated neurophysiological indices of AB. SIGNIFICANCE: Results provide evidence for attention-relevant ERPs as outcomes of ABM treatment responsivity and suggest that ABM may be most beneficial for those with more severe anxiety symptoms.

JIB-04, a Pan-Inhibitor of Histone Demethylases, Targets Histone-Lysine-Demethylase-Dependent AKT Pathway, Leading to Cell Cycle Arrest and Inhibition of Cancer Stem-Like Cell Properties in Hepatocellular Carcinoma Cells.

JIB-04, a pan-histone lysine demethylase (KDM) inhibitor, targets drug-resistant cells, along with colorectal cancer stem cells (CSCs), which are crucial for cancer recurrence and metastasis. Despite the advances in CSC biology, the effect of JIB-04 on liver CSCs (LCSCs) and the malignancy of hepatocellular carcinoma (HCC) has not been elucidated yet. Here, we showed that JIB-04 targeted KDMs, leading to the growth inhibition and cell cycle arrest of HCC, and abolished the viability of LCSCs. JIB-04 significantly attenuated CSC tumorsphere formation, growth, relapse, migration, and invasion in vitro. Among KDMs, the deficiency of KDM4B, KDM4D, and KDM6B reduced the viability of the tumorspheres, suggesting their roles in the function of LCSCs. RNA sequencing revealed that JIB-04 affected various cancer-related pathways, especially the PI3K/AKT pathway, which is crucial for HCC malignancy and the maintenance of LCSCs. Our results revealed KDM6B-dependent AKT2 expression and the downregulation of E2F-regulated genes via JIB-04-induced inhibition of the AKT2/FOXO3a/p21/RB axis. A ChIP assay demonstrated JIB-04-induced reduction in H3K27me3 at the AKT2 promoter and the enrichment of KDM6B within this promoter. Overall, our results strongly suggest that the inhibitory effect of JIB-04 on HCC malignancy and the maintenance of LCSCs is mediated via targeting the KDM6B-AKT2 pathway, indicating the therapeutic potential of JIB-04.

Transcranial Electrical Stimulation for Psychiatric Disorders in Adults: A Primer.

Transcranial electrical stimulation (tES) comprises noninvasive neuromodulation techniques that deliver low-amplitude electrical currents to targeted brain regions with the goal of modifying neural activities. Expanding evidence from the past decade, specifically using transcranial direct current simulation and transcranial alternating current stimulation, presents promising applications of tES as a treatment for psychiatric disorders. In this review, the authors discuss the basic technical aspects and mechanisms of action of tES in the context of clinical research and practice and review available evidence for its clinical use, efficacy, and safety. They also review recent advancements in use of tES for the treatment of depressive disorders, schizophrenia, substance use disorders, and obsessive-compulsive disorder. Findings largely support growing evidence for the safety and efficacy of tES in the treatment of patients with resistance to existing treatment options, particularly demonstrating promising treatment outcomes for depressive disorders. Future directions of tES research for optimal application in clinical settings are discussed, including the growing home-based, patient-friendly methods and the potential pairing with existing pharmacological or psychotherapeutic treatments for enhanced outcomes. Finally, neuroimaging advancements may provide more specific mapping of brain networks, aiming at more precise tES therapeutic targeting in the treatment of psychiatric disorders.

Evaluation of protein descriptors in computer-aided rational protein engineering tasks and its application in property prediction in SARS-CoV-2 spike glycoprotein.

The importance of protein engineering in the research and development of biopharmaceuticals and biomaterials has increased. Machine learning in computer-aided protein engineering can markedly reduce the experimental effort in identifying optimal sequences that satisfy the desired properties from a large number of possible protein sequences. To develop general protein descriptors for computer-aided protein engineering tasks, we devised new protein descriptors, one sequence-based descriptor (PCgrades), and three structure-based descriptors (PCspairs, 3D-SPIEs_5.4 Å, and 3D-SPIEs_8Å). While the PCgrades and PCspairs include general and statistical information in physicochemical properties in single and pairwise amino acids respectively, the 3D-SPIEs include specific and quantum-mechanical information with parameterized quantum mechanical calculations (FMO2-DFTB3/D/PCM). To evaluate the protein descriptors, we made prediction models with the new descriptors and previously developed descriptors for diverse protein datasets including protein expression and binding affinity change in SARS-CoV-2 spike glycoprotein. As a result, the newly devised descriptors showed a good performance in diverse datasets, in which the PCspairs showed the best performance ( R 2 = 0.783 for protein expression and R 2 = 0.711 for binding affinity). As a result, the newly devised descriptors showed a good performance in diverse datasets, in which the PCspairs showed the best performance. Similar approaches with those descriptors would be promising and useful if the prediction models are trained with sufficient quantitative experimental data from high-throughput assays for industrial enzymes or protein drugs.

Mobile Attention Bias Modification Training Is a Digital Health Solution for Managing Distress in Multiple Sclerosis: A Pilot Study in Pediatric Onset.

Introduction: Emotional health is important dimension of care for patients living with pediatric onset multiple sclerosis (POMS), but few options are available for stress and anxiety reduction. The high burden of interventions requiring regular in person and onsite visits for treatment are less feasible. Attention bias modification training (ABMT) is effective for anxiety reduction in adult and adolescent populations. We tested the feasibility and preliminary efficacy of ABMT delivered through a mobile gamified version as a digital emotional health tool for patients with POMS. Methods: Participants with POMS were consecutively recruited from the NYU Langone Pediatric MS Care Center and enrolled to complete a 1-month intervention with use of the Personal Zen ABMT app on their mobile personal device. Feasibility was evaluated by use of the 1-month intervention and efficacy was measured by changes in depression, anxiety, and affect. Results: A total n = 35 patients with POMS were enrolled in the study (M age = 17.7, SD = 2.2 years, range 14-23). Feasibility criteria were met with 74% completing the full intervention time, and 100% of the sample completing at least 50% of targeted intervention use. Initial efficacy was found for a reduction in negative affect from baseline to intervention end [M = 22.88, SD = 9.95 vs. M = 19.56, SD = 7.37; t (33) = 2.47, p = 0.019]. Anxiety also significantly decreased from pre to post-intervention in adults [M = 11.82, SD = 9.90 vs. M = 7.29, SD = 7.17; t (16) = 3.88, p = 0.001] and youth [M = 51.14, SD = 19.66 vs. M = 40.86, SD = 27.48; t (13) = 3.17, p = 0.007]. Conclusion: Mobile ABMT with the Personal Zen app is a feasible and accessible digital emotional health tool for patients with POMS and may have broader application for managing distress across chronic neurological conditions.

Absence Makes the Mind Grow Fonder: Reconceptualizing Studies of Safety Learning in Translational Research on Anxiety.

Overgeneralized fear (OGF), or indiscriminate fear responses to signals of threat and nonthreat, is a well-studied cognitive mechanism in human anxiety. Anxiety-related OGF has been studied primarily through fear-learning paradigms and conceptualized as overly exaggerated learning of cues signaling imminent threat. However, the role of safety learning in OGF has not only received much less empirical attention but has been fundamentally conceptualized as learning about the absence of threat rather than the presence of safety. As a result, the relative contributions of exaggerated fear learning and weakened safety learning to anxiety-related OGF remain poorly understood, as do the potentially unique biological and behavioral underpinnings of safety learning. The present review outlines these gaps by, first, summarizing animal and human research on safety learning related to anxiety and OGF. Second, we outline innovations in methods to tease apart unique biological and behavioral contributions of safety learning to OGF. Lastly, we describe clinical and treatment implications of this framework for translational research relevant to human anxiety.

Transcranial Direct Current Stimulation (tDCS) Augments the Effects of Gamified, Mobile Attention Bias Modification.

Anxiety-related attention bias (AB) is the preferential processing of threat observed in clinical and sub-clinical anxiety. Attention bias modification training (ABMT) is a computerized cognitive training technique designed to systematically direct attention away from threat and ameliorate AB, but mixed and null findings have highlighted gaps in our understanding of mechanisms underlying ABMT and how to design the most effective delivery systems. One neuromodulation technique, transcranial direct current stimulation (tDCS) across the pre-frontal cortex (PFC) may augment the effects of ABMT by strengthening top-down cognitive control processes, but the evidence base is limited and has not been generalized to current approaches in digital therapeutics, such as mobile applications. The present study was a single-blind randomized sham-controlled design. We tested whether tDCS across the PFC, vs. sham stimulation, effectively augments the beneficial effects of a gamified ABMT mobile app. Thirty-eight adults (Mage = 23.92, SD = 4.75; 18 females) evidencing low-to-moderate anxiety symptoms were randomly assigned to active or sham tDCS for 30-min while receiving ABMT via a mobile app. Participants reported on potential moderators of ABMT, including life stress and trait anxiety. ECG was recorded during a subsequent stressor to generate respiratory sinus arrhythmia (RSA) suppression as a metric of stress resilience. ABMT delivered via the app combined with tDCS (compared to sham) reduced AB and boosted stress resilience measured via RSA suppression, particularly for those reporting low life stress. Our results integrating tDCS with ABMT provide insight into the mechanisms of AB modulation and support ongoing evaluations of enhanced ABMT reliability and effectiveness via tDCS.

EEG Correlates of Involuntary Cognitions in the Reflexive Imagery Task.

The Reflexive Imagery Task (RIT) reveals that the activation of sets can result in involuntary cognitions that are triggered by external stimuli. In the basic RIT, subjects are presented with an image of an object (e.g., CAT) and instructed to not think of the name of the object. Involuntary subvocalizations of the name (the RIT effect) arise on roughly 80% of the trials. We conducted an electroencephalography (EEG) study to explore the neural correlates of the RIT effect. Subjects were presented with one object at a time in one condition and two objects simultaneously in another condition. Five regions were defined by electrode sites: frontal (F3-F4), parietal (P3-P4), temporal (T3-T4), right hemisphere (F4-P4), and left hemisphere (F3-P3). We focused on the alpha (8-13 Hz), beta (13-30 Hz), delta (0.01-4 Hz), and theta (4-8 Hz) frequencies.

The late positive potential as a neurocognitive index of emotion regulatory flexibility.

A growing body of research has examined regulatory flexibility as the ability to dynamically modulate emotional expression and experience (Bonanno & Burton, 2013). The late positive potential (LPP), an event-related potential reflecting processing of emotionally-evocative stimuli, is sensitive to emotion regulation (ER) or the psychological processes that underlie the experience, expression, and management of emotions. However, few studies have used the LPP to index regulatory flexibility or tested its association with self-reported emotional well-being and ER. The results of the current study showed that regulatory flexibility indexed via the LPP was associated with self-reported use of specific ER strategies. Further, greater regulatory flexibility measured as the full LPP regulatory range (indexed following prompts to enhance and suppress emotional responses to stimuli) was specifically and uniquely associated with greater self-reported coping flexibility. Findings provide preliminary support for this neurocognitive approach to conceptualizing and assessing regulatory flexibility.

Involuntary Entry Into Consciousness From the Activation of Sets: Object Counting and Color Naming.

High-level cognitions can enter consciousness through the activation of certain action sets and the presentation of external stimuli ("set-based entry," for short). Set-based entry arises in a manner that is involuntary and systematic. In the Reflexive Imagery Task, for example, subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We examined whether or not set-based entry can also occur in the case of involuntary counting. Subjects in Experiment 1A were instructed to not count the number of objects presented in an array. Involuntary counting arose on a high proportion of the trials (a mean proportion of ∼0.90) for stimulus arrays having 2-5 objects, and such counting arose less frequently across trials when the array consisted of 6-10 objects (a mean proportion of ∼0.21). The data from Experiment 1B revealed that, when people choose to perform Set X, they also experience thoughts about an unselected Set (Set Y). Subjects were trained on one set (e.g., to "color name") and then, when presented with stimuli, were given the choice to perform the trained set or a novel set. Consistent with theories proposing that the conscious contents represent several potential action plans, subjects were equally likely to experience set-related imagery or set-unrelated imagery. Our findings regarding set-based entry are relevant to many subfields of psychology and neuroscience (e.g., the study of high-level mental processes, attention, imagery, and action control).

The reflexive imagery task: An experimental paradigm for neuroimaging.

High-level cognitions can be triggered into consciousness through the presentation of external stimuli and the activation of certain action sets. These activations arise in a manner that is involuntary, systematic and nontrivial. For example, in the Reflexive Imagery Task (RIT), subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We review the findings from this paradigm, discuss neural findings that are relevant to the RIT, and present new data that further corroborate the reliability and robustness of the RIT, a paradigm that could be coupled with neuroimaging technologies. We developed an RIT variant in which two, non-focal objects are presented simultaneously. In previous RITs, visual objects were presented only one at a time, in the center of the screen, and subjects were instructed to focus on the center of the screen, where these objects were presented. Replicating the RIT effect, involuntary subvocalizations still occurred on a high proportion of trials (M = 0.78). An RIT effect arose for both objects on a considerable proportion of the trials (M = 0.35). These findings were replicated in a second experiment having a different sample of subjects. Our findings are relevant to many subfields of neuroscience (e.g., the study of high-level mental processes, attention, imagery and action control).

The reflexive imagery task: An experimental paradigm for neuroimaging.

High-level cognitions can be triggered into consciousness through the presentation of external stimuli and the activation of certain action sets. These activations arise in a manner that is involuntary, systematic and nontrivial. For example, in the Reflexive Imagery Task (RIT), subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We review the findings from this paradigm, discuss neural findings that are relevant to the RIT, and present new data that further corroborate the reliability and robustness of the RIT, a paradigm that could be coupled with neuroimaging technologies. We developed an RIT variant in which two, non-focal objects are presented simultaneously. In previous RITs, visual objects were presented only one at a time, in the center of the screen, and subjects were instructed to focus on the center of the screen, where these objects were presented. Replicating the RIT effect, involuntary subvocalizations still occurred on a high proportion of trials (M = 0.78). An RIT effect arose for both objects on a considerable proportion of the trials (M = 0.35). These findings were replicated in a second experiment having a different sample of subjects. Our findings are relevant to many subfields of neuroscience (e.g., the study of high-level mental processes, attention, imagery and action control).

Do people with schizophrenia experience more negative emotion and less positive emotion in their daily lives? A meta-analysis of experience sampling studies.

Research on emotion experience in response to valenced stimuli has consistently shown that people with schizophrenia have the capacity to experience emotion. Specifically, people with schizophrenia report similar experiences to both positive and negative emotion-eliciting stimuli as individuals without the disorder. However, it is less clear if people with schizophrenia experience similar levels of positive emotion and negative emotion outside of standardized laboratory contexts, as in their daily lives. One reliable method for assessing emotion experience in schizophrenia has been the Experience Sampling Method (ESM), or Ecological Momentary Assessment (EMA). Using the PRISMA guidelines for meta-analysis, we reviewed the literature for all studies that included people with and without schizophrenia, and that included a positive or negative emotion assessment during participants' daily lives. The current study is a meta-analysis of 12 EMA studies of emotion experience, which included a total of 619 people with schizophrenia and 730 healthy controls. Results indicate that people with schizophrenia consistently report more negative and less positive emotion than healthy control participants. These findings differ from laboratory-based studies, which may be due to several factors, including environmental differences, effects of the disorder that appear more clearly in daily life, or additional concerns, such as depression, which has been shown to be related to negative emotion in schizophrenia. Importantly, these findings are in line with questionnaire-based measures of emotion experience, lending some support for their use in research and clinical settings.

Involuntary symbol manipulation (Pig Latin) from external control: Implications for thought suppression.

In ironic processing, one is more likely to think about something (e.g., white bears) when instructed to not think about that thing. Entry into consciousness of such content may be automatic, reflecting the 'encapsulated' nature of the generation of conscious contents. Based on this research, the Reflexive Imagery Task (RIT) reveals that, following the activation of action sets, conscious contents can arise involuntarily and systematically in response to external stimuli. In the most basic version of this paradigm, participants are presented with visual objects and instructed to not think of the names of the objects, which is challenging. Here, we addressed one criticism of the RIT-that the effect arises only for automatic processes (e.g., forms of cued-memory retrieval) and not for more complex processes (e.g., symbol manipulation). Participants were first trained to perform a word-manipulation task similar to the game of Pig Latin (e.g., "CAR" becomes "AR-CAY"). Such a task involves complex symbol manipulations that are associated with processes in frontal cortex. After training, participants were instructed to not transform stimulus words in this way. The RIT effect still arose under these conditions. This striking finding is relevant to theories of cognitive control, psychopathology, and conscious/unconscious processing.

Internally generated conscious contents: interactions between sustained mental imagery and involuntary subvocalizations.

The conscious field includes not only representations about external stimuli (e.g., percepts), but also conscious contents associated with internal states, such as action-related intentions (e.g., urges). Although understudied, the latter may provide unique insights into the nature of consciousness. To illuminate these phenomena, in a new experimental paradigm [Reflexive Imagery Task (RIT)], participants were instructed to not subvocalize the names of visually-presented objects. Each object was presented for 10 s on a screen. Participants indicated whenever they involuntarily subvocalized the object name. Research has revealed that it is difficult to suppress such subvocalizations, which occur on over 80% of the trials. Can the effect survive if one intentionally generates a competing (internally-generated) conscious content? If so, this would suggest that intentional and unintentional contents can co-exist simultaneously in consciousness in interesting ways. To investigate this possibility, in one condition, participants were instructed to reiteratively subvocalize a speech sound ("da, da, da") throughout the trial. This internally generated content is self-generated and intentional. Involuntary subvocalizations of object names still arose on over 80% of the trials. One could hypothesize that subvocalizations occurred because of the pauses between the intended speech sounds, but this is inconsistent with the observation that comparable results arose even when participants subvocalized a continuous, unbroken hum ("daaa….") throughout the trial. Regarding inter-content interactions, the continuous hum and object name seem to co-exist simultaneously in consciousness. This intriguing datum requires further investigation. We discuss the implications of this new paradigm for the study of internally-generated conscious contents.