Visual mental imagery: Evidence for a heterarchical neural architecture.

Theories of Visual Mental Imagery (VMI) emphasize the processes of retrieval, modification, and recombination of sensory information from long-term memory. Yet, only few studies have focused on the behavioral mechanisms and neural correlates supporting VMI of stimuli from different semantic domains. Therefore, we currently have a limited understanding of how the brain generates and maintains mental representations of colors, faces, shapes - to name a few. Such an undetermined scenario renders unclear the organizational structure of neural circuits supporting VMI, including the role of the early visual cortex. We aimed to fill this gap by reviewing the scientific literature of five semantic domains: visuospatial, face, colors, shapes, and letters imagery. Linking theory to evidence from over 60 different experimental designs, this review highlights three main points. First, there is no consistent activity in the early visual cortex across all VMI domains, contrary to the prediction of the dominant model. Second, there is consistent activity of the frontoparietal networks and the left hemisphere's fusiform gyrus during voluntary VMI irrespective of the semantic domain investigated. We propose that these structures are part of a domain-general VMI sub-network. Third, domain-specific information engages specific regions of the ventral and dorsal cortical visual pathways. These regions partly overlap with those found in visual perception studies (e.g., fusiform face area for faces imagery; lingual gyrus for color imagery). Altogether, the reviewed evidence suggests the existence of domain-general and domain-specific mechanisms of VMI selectively engaged by stimulus-specific properties (e.g., colors or faces). These mechanisms would be supported by an organizational structure mixing vertical and horizontal connections (heterarchy) between sub-networks for specific stimulus domains. Such a heterarchical organization of VMI makes different predictions from current models of VMI as reversed perception. Our conclusions set the stage for future research, which should aim to characterize the spatiotemporal dynamics and interactions among key regions of this architecture giving rise to visual mental images.

Guided LGBTQ-affirmative internet cognitive-behavioral therapy for sexual minority youth's mental health: A randomized controlled trial of a minority stress treatment approach.

OBJECTIVE: LGBTQ-affirmative cognitive-behavioral therapy (CBT) addresses the adverse impacts of minority stress. However, this treatment has rarely been tested in randomized controlled trials with LGBTQ youth and never using an asynchronous online platform for broad reach. This study examined the feasibility, acceptability, preliminary efficacy, and multi-level stigma moderators of LGBTQ-affirmative internet-based CBT (ICBT). METHOD: Participants were 120 LGBTQ youth (ages 16-25; 37.5% transgender or non-binary; 75.8% assigned female at birth; 49.2% non-Latino White) living across 38 U.S. states and reporting depression and/or anxiety symptoms. Participants were randomized to receive 10 sessions of LGBTQ-affirmative ICBT or only complete 10 weekly assessments of mental and behavioral health and minority stress; all completed measures of psychological distress, depression, anxiety, suicidal thoughts, alcohol use, and HIV-transmission-risk behavior at baseline and 4 and 8 months post-baseline; 20 LGBTQ-affirmative ICBT participants completed a qualitative interview regarding intervention acceptability. RESULTS: Participants randomized to LGBTQ-affirmative ICBT completed, on average, 6.08 (SD = 3.80) sessions. Participants reported that LGBTQ-affirmative ICBT was helpful and engaging and provided suggestions for enhancing engagement. Although most outcomes decreased over time, between-group comparisons were small and non-significant. LGBTQ-affirmative ICBT was more efficacious in reducing psychological distress than assessment-only for participants in counties high in anti-LGBTQ bias (b = -1.73, p = 0.001, 95% CI [-2.75, -0.70]). Session dosage also significantly predicted reduced depression and anxiety symptoms. CONCLUSIONS: LGBTQ-affirmative ICBT represents a feasible and acceptable treatment. Future research can identify more efficacious approaches and modalities for engaging LGBTQ youth, especially those living under stigmatizing conditions, who might benefit most.

Body Image and High-Risk Weight and Shape Control Behaviors Among Transgender and Nonbinary Young Adults: The Role of Sexual Assault.

Purpose: Transgender and nonbinary (TNB) populations experience disproportionate rates of sexual assault. Despite evidence from cisgender samples linking sexual assault exposure to body image concerns and disordered eating behaviors, such as weight and shape control behaviors (WSCBs), little is known about these relationships in TNB people. The purpose of this study was to assess associations among past-year sexual assault exposure, body areas satisfaction, body weight esteem, and high-risk WSCBs in a sample of TNB young adults. Methods: A sample of 714 participants completed a cross-sectional online survey. Multivariable linear and logistic models were fit to determine associations between constructs of interest. Natural effects mediation analyses assessed for potential mediation of the relationship between sexual assault and WSCBs by body areas satisfaction and body weight esteem. Analyses were stratified by three gender identity categories. Results: Past-year sexual assault exposure was associated with significantly decreased body areas satisfaction, but only for nonbinary participants. No significant association was found between sexual assault and body weight esteem. Sexual assault was associated with significantly increased risk for WSCBs across gender identity categories. No mediation of these relationships by body areas satisfaction and body weight esteem was observed. Conclusion: Findings support clinical consideration of WSCBs in TNB survivors of sexual assault. Results suggest that multiple factors, including body image and sexual assault, may contribute separately to disordered eating behaviors in TNB young adults.