Avoidant symptoms in PTSD predict fear circuit activation during multimodal fear extinction

Convergent evidence suggests that individuals with posttraumatic stress disorder (PTSD) exhibit exaggerated avoidance behaviors as well as abnormalities in Pavlonian fear conditioning. However, the link between the two features of this disorder is not well understood. In order to probe the brain basis of aberrant extinction learning in PTSD, we administered a multimodal classical fear conditioning/extinction paradigm that incorporated affectively relevant information from two sensory channels (visual and tactile) while participants underwent fMRI scanning. The sample consisted of fifteen OEF/OIF veterans with PTSD. In response to conditioned cues and contextual information, greater avoidance symptomatology was associated with greater activation in amygdala, hippocampus, vmPFC, dmPFC, and insula, during both fear acquisition and fear extinction. Heightened responses to previously conditioned stimuli in individuals with more severe PTSD could indicate a deficiency in safety learning, consistent with PTSD symptomatology. The close link between avoidance symptoms and fear circuit activation suggests that this symptom cluster may be a key component of fear extinction deficits in PTSD and/or may be particularly amenable to change through extinction-based therapie

Impaired contextual modulation of memories in PTSD: an fMRI and psychophysiological study of extinction retention and fear renewal

Post-traumatic stress disorder (PTSD) patients display pervasive fear memories, expressed indiscriminately. Proposed mechanisms include enhanced fear learning and impaired extinction or extinction recall. Documented extinction recall deficits and failure to use safety signals could result from general failure to use contextual information, a hippocampus-dependent process. This can be probed by adding a renewal phase to standard conditioning and extinction paradigms. Human subjects with PTSD and combat controls were conditioned (skin conductance response), extinguished, and tested for extinction retention and renewal in a scanner (fMRI). Fear conditioning (light paired with shock) occurred in one context, followed by extinction in another, to create danger and safety contexts. The next day, the extinguished conditioned stimulus (CS+E) was re-presented to assess extinction recall (safety context) and fear renewal (danger context). PTSD patients showed impaired extinction recall, with increased skin conductance and heightened amygdala activity to the extinguished CS+ in the safety context. However, they also showed impaired fear renewal; in the danger context, they had less skin conductance response to CS+E and lower activity in amygdala and ventral-medial prefrontal cortex compared with combat controls. Control subjects displayed appropriate contextual modulation of memory recall, with extinction (safety) memory prevailing in the safety context, and fear memory prevailing in the danger context. PTSD patients could not use safety context to sustain suppression of extinguished fear memory, but they also less effectively used danger context to enhance fear. They did not display globally enhanced fear expression, but rather showed a globally diminished capacity to use contextual information to modulate fear expression

DIT Library Services: An Evolving Learning Environment

DIT Library Services: an evolving learning environment The library as a place of learning has seen progressive change. DIT Library Services is listening and responding to the student need for a library service that supports all their learning requirements and learning styles. A service designed to reach them at their point of need

Health Behaviors and their Impact on Bariatric Surgery

Bariatric surgery is a long-term solution when dealing with obesity. The two most performed surgeries are sleeve gastrectomy (SG) and Roux-en-Y Gastric Bypass (RYGB). Both surgeries required a long-term follow-up with the patients as well as drastic changes in their lifestyle due to the alterations in their digestive system. For that reason, it is important to track health-related behaviors to keep a record of the patient’s health. In addition to a drastic change in the patient’s life, some of the health-related behaviors such as nocturnal eating and binge eating can lead to poorer surgical outcomes such as less weight loss. For that reason, there needs to be standardization around pre-health assessments in the bariatric world. The purpose of this literature review is to analyze preoperative surgery assessments for health behaviors including binge eating disorder (BED), nocturnal eating syndrome (NES), and alcohol use disorder (AUD).https://digitalcommons.unmc.edu/surp2022/1035/thumbnail.jp

Access to prompt diagnosis: The missing link in preventing mental health disorders associated with neglected tropical diseases

Globally, there are an estimated 1 billion people suffering from at least one of the 20 neglected tropical diseases (NTDs) prioritized by the World Health Organization (WHO). Prevalent in tropical and subtropical regions, this group of NTDs comprises diverse diseases, including vector-borne parasitic diseases (such as human African trypanosomiasis [HAT], Chagas disease, and leishmaniasis), skin diseases caused by environmental bacteria (such as Buruli ulcer [BU]), foodborne parasitic diseases (such as taeniasis/cysticercosis) or snake bite envenoming, which—together with scabies and other ectoparasites, mycetoma, and deep mycoses—were recently added to the list [1]. Despite their differences, NTDs are synonymous with poverty, life-long disability, stigma, and discrimination, not to mention the lack of effective control tools such as vaccines, diagnostics, and drugs.S

Mapping Indigenous Self-Determination in Highland Guatemala

The challenges of building research partnerships around community mapping are critically reviewed in reference to the politics of heritage and identity among Indigenous Maya communities in highland Guatemala. This paper discusses how the goals and interests of archaeologists meshed with those of indigenous mappers in five communities that chose to participate in the mapping program. Based on responses to a survey about the mapping project, participants report joining in order to enhance self-determination, gain cartographic literacy, and improve life opportunities. Community authority over the project and a broad base of participation (including young and old, male and female) proved essential to the program, which combined traditional practices of governance with new technologies. This paper describes the community organizational model and protocols for selecting features and topics for thematic maps as well as for gaining community consensus on map content. Finally, it reflects on this transmodern approach to indigenous mapping and the future of research partnerships

A Real Time Optical Biosensor Assay for Amoxicillin and Other β-Lactams in Water Samples

Antibiotic contamination of drinking water and sewage is a matter of environmental and public health concern. Traditionally, ELISA or HPLC methods have been used to detect and measure antibiotic contamination. By applying an optical biosensing method, biolayer inteferometry (BLI), we have developed a kinetic competition binding assay capable of quantitating less than 1ppm (~33 μM) amoxicillin. Similar to surface plasmon resonance, BLI senses changes that occur upon binding of one molecule to another near a surface to measure association and dissociation. Immobilized amoxicillin was used to screen for binding against an analyte solution of anti-amoxicillin equilibrated with amoxicillin-containing water samples, yielding binding that fit a one-state model. Maximal binding correlated highly with amoxicillin concentration. Simplified analysis of samples from water and sewage treatment plants in Georgia allowed quantitation without kinetic modeling. The assay is sensitive, cost-effective, fast and readily adaptable to a variety of samples and other small molecules

A Real Time Optical Biosensor Assay for Amoxicillin And Other β-Lactams in Water Samples

Antibiotic contamination of drinking water and sewage is a matter of environmental and public health concern. Traditionally, ELISA or HPLC methods have been used to detect and measure antibiotic contamination. By applying an optical biosensing method, biolayer inteferometry (BLI), we have developed a kinetic competition binding assay capable of quantitating less than lppm (~33 μM) amoxicillin. Similar to surface plasmon resonance, BLI senses changes that occur upon binding of one molecule to another near a surface to measure association and dissociation. Immobilized amoxicillin was used to screen for binding against an analyte solution of anti-amoxicillin equilibrated with amoxicillin-containing water samples, yielding binding that fit a one-state model. Maximal binding correlated highly with amoxicillin concentration. Simplified analysis of samples from water and sewage treatment plants in Georgia allowed quantitation without kinetic modeling. The assay is sensitive, cost-effective, fast and readily adaptable to a variety of samples and other small molecules

Best Practices User Guide: Youth Engagement

This user guide, funded by the Centers for Disease Control and Prevention, focuses on the role youth play in advancing policy as part of a comprehensive tobacco control program. This guide will provide tobacco control program managers with information on the best practices for engaging youth as a part of a comprehensive program. Youth involvement can lead to important policy and social norm changes, and advance the fight against pro-tobacco influences.https://openscholarship.wustl.edu/cphss/1104/thumbnail.jp

Childhood poverty is associated with altered hippocampal function and visuospatial memory in adulthood

Childhood poverty is a risk factor for poorer cognitive performance during childhood and adulthood. While evidence linking childhood poverty and memory deficits in adulthood has been accumulating, underlying neural mechanisms are unknown. To investigate neurobiological links between childhood poverty and adult memory performance, we used functional magnetic resonance imaging (fMRI) during a visuospatial memory task in healthy young adults with varying income levels during childhood. Participants were assessed at age 9 and followed through young adulthood to assess income and related factors. During adulthood, participants completed a visuospatial memory task while undergoing MRI scanning. Patterns of neural activation, as well as memory recognition for items, were assessed to examine links between brain function and memory performance as it relates to childhood income. Our findings revealed associations between item recognition, childhood income level, and hippocampal activation. Specifically, the association between hippocampal activation and recognition accuracy varied as a function of childhood poverty, with positive associations at higher income levels, and negative associations at lower income levels. These prospective findings confirm previous retrospective results detailing deleterious effects of childhood poverty on adult memory performance. In addition, for the first time, we identify novel neurophysiological correlates of these deficits localized to hippocampus activation