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The ability of bilateral medial temporal lobe amnesic patients (MT; n = 8) and normal participants (NC; n = 8) to acquire a conditional discrimination in trace and delay eyeblink conditioning paradigms was investigated. Experiment 1 assessed trace conditional discrimination learning by using a light conditional stimulus (S+/S-) and tone conditioned stimulus (CS) separated by a 1-s trace. NCs responded differentially on S+ trials (mean percent conditioned responses = 66) versus S - trials (30), whereas MTs were impaired in their acquisition of the conditional discrimination (S+ = 51, S- = 43). In Experiment 2, the temporal separation was eliminated. NCs acquired the conditional discrimination (S + = 70, S- = 29). MTs were unable to respond differentially (S+ = 42, S- = 37). The findings indicate that the hippocampal system is essential in acquiring a conditional discrimination, even in a delay paradigm. [ABSTRACT FROM AUTHOR]

Objective. Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) are common among US veterans of Operation Enduring Freedom/ Operation Iraqi Freedom/Operation New Dawn (OEF/ OIF/OND). We postulated that these injuries may modulate pain processing in these individuals and affect their subjective pain levels. Design. Cross-sectional. Subjects. 310 deployed service members of OEF/ OIF/OND without a lifetime history of moderate or severe TBI were included in this study. Methods. All participants completed a comprehensive evaluation for Blast Exposure, mTBI, PTSD, and Pain Levels. The Boston Assessment of TBI-Lifetime Version (BAT-L) was used to assess blast exposure and potential brain injury during military service. The Clinician-Administered PTSD Scale (CAPS) characterized presence and severity of PTSD. The Visual Analog Scale (VAS) was used to assess pain intensity over the previous month before the interview, with higher scores indicative of worse pain. Statistical analysis was performed by ANOVA and results were adjusted for co-morbidities, clinical characteristics and demographic data. Results. In comparison to control participants (veterans without mTBI or current PTSD), veterans with both current PTSD and mTBI reported the highest pain intensity levels, followed by veterans with PTSD only (P<0.0001 and P = 0.0005, respectively). Pain levels in veterans with mTBI only were comparable to control participants. Conclusions. Comorbid PTSD and mTBI is associated with increased self-reported pain intensity. mTBI alone was not associated with increased pain. [ABSTRACT FROM AUTHOR]

Background: Adolescence is a critical period for neural development and has been associated with high rates of alcohol abuse. This research examined potential long‐term brain and behavioral effects of early versus late‐onset adolescent binge drinking in an adult sample of post‐9/11 Veterans. Methods: We compared cortical thickness measures in Veterans with a history of binge drinking that began before the age of 15 (n = 50; mean age = 32.1 years) to those with a history of binge drinking with onset after the age of 15 (n = 300; mean age = 32.1 years). Data processing was conducted with FreeSurfer. A targeted neuropsychological battery (Digit Span test, Delis‐Kaplan Executive Function System Color‐Word Interference Test, California Verbal Learning Test‐II) was used to examine the relationships between cortical thickness and attention, memory, and inhibition. A reference group of social drinkers with no history of early binge drinking (n = 31) was used to provide normative data. Results: Early‐onset adolescent binge drinkers (EBD) had greater cortical thickness in several regions than late‐onset adolescent binge drinkers (LBD); both binge‐drinking groups had greater cortical thickness than the reference group. There was a stronger negative association between cortical thickness and age in EBDs than LBDs in the (i) lateral orbitofrontal cortex, (ii) supramarginal gyrus, (iii) paracentral lobule, and (iv) anterior caudal cingulate. Poorer performance on the attention and inhibition tasks in the EBDs was also associated with thicker cortices. Conclusions: This study demonstrates greater cortical thickness across frontoparietal regions in adults who began binge drinking in early versus late adolescence. A stronger negative association between cortical thickness and age in the EBDs suggests that early‐onset adolescent binge drinking may be associated with accelerated cortical thinning. Thicker cortex in these regions, which are known to mediate inhibitory control, may increase impulsive behavior and contribute to the risk of alcohol addiction. [ABSTRACT FROM AUTHOR]

Many US veterans of Afghanistan and Iraq have multiple physical and psychiatric problems. A major focus of research has been on determining the effects of mild Traumatic Brain Injury (mTBI), but mTBI is rarely diagnosed in the absence of co-occurring conditions such as blast exposure, post-traumatic stress disorder (PTSD), depression, substance abuse, etc. These potentially interactive psychological and physical conditions produce complex patterns of cognitive, psychological, and physical symptoms that impede civilian reintegration and complicate efficient and effective treatment planning. The Translational Research Center for TBI and Stress Disorders (TRACTS) has developed a multidisciplinary approach to the assessment of deployment trauma and its consequences in veterans of these wars. The prospective TRACTS longitudinal cohort study conducts state-of-the-art assessments in the domains of biomedical function, lifetime head trauma, psychological function encompassing deployment experience and lifetime exposure to traumatic events, neuropsychological function, and structural and functional neuroimaging. The TRACTS longitudinal cohort study is the first of its kind to comprehensively evaluate lifetime incidence of TBI and PTSD in these veterans, in addition to those incurred during military deployment. The protocol has begun to reveal information that will help improve understanding of the complex pathophysiology associated with co-occurring mTBI and related stress disorders. [ABSTRACT FROM AUTHOR]