Effects of OEF/OIF-Related Physical and Emotional Co-Morbidities on Associative Learning: Concurrent Delay and Trace Eyeblink Classical Conditioning

This study examined the performance of veterans and active duty personnel who served in Operation Enduring Freedom and/or Operation Iraqi Freedom (OEF/OIF) on a basic associative learning task. Eighty-eight individuals participated in this study. All received a comprehensive clinical evaluation to determine the presence and severity of posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI). The eyeblink conditioning task was composed of randomly intermixed delay and trace conditioned stimulus (CS) and unconditioned stimulus (US) pairs (acquisition) followed by a series of CS only trials (extinction). Results revealed that those with a clinical diagnosis of PTSD or a diagnosis of PTSD with comorbid mTBI acquired delay and trace conditioned responses (CRs) to levels and at rates similar to a deployed control group, thus suggesting intact basic associative learning. Differential extinction impairment was observed in the two clinical groups. Acquisition of CRs for both delay and trace conditioning, as well as extinction of trace CRs, was associated with alcoholic behavior across all participants. These findings help characterize the learning and memory function of individuals with PTSD and mTBI from OEF/OIF and raise the alarming possibility that the use of alcohol in this group may lead to more significant cognitive dysfunction

Reduced cortical thickness with increased lifetime burden of PTSD in OEF/OIF Veterans and the impact of comorbid TBI☆

Posttraumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) in military personnel is increasing dramatically following the OEF/OIF conflicts and is associated with alterations to brain structure. The present study examined the relationship between PTSD and cortical thickness, and its possible modification by mTBI, in a 104-subject OEF/OIF veteran cohort ranging in age from 20 to 62 years. For each participant, two T1-weighted scans were averaged to create high-resolution images for calculation of regional cortical thickness. PTSD symptoms were assessed using the Clinician Administered PTSD Scale (CAPS) and scores were derived based on the previous month's symptoms (“current”) and a Cumulative Lifetime Burden of PTSD (CLB-P) reflecting the integral of CAPS scores across the lifetime. Mild TBI was diagnosed using the Boston Assessment of TBI-Lifetime (BAT-L). Results demonstrated a clear negative relationship between current PTSD severity and thickness in both postcentral gyri and middle temporal gyri. This relationship was stronger and more extensive when considering lifetime burden (CLB-P), demonstrating the importance of looking at trauma in the context of an individual's lifetime, rather than only at their current symptoms. Finally, interactions with current PTSD only and comorbid current PTSD and mTBI were found in several regions, implying an additive effect of lifetime PTSD and mTBI on cortical thickness

Lack of MEF2A Δ7aa mutation in Irish families with early onset ischaemic heart disease, a family based study

BACKGROUND: Ischaemic heart disease (IHD) is a complex disease due to the combination of environmental and genetic factors. Mutations in the MEF2A gene have recently been reported in patients with IHD. In particular, a 21 base pair deletion (Δ7aa) in the MEF2A gene was identified in a family with an autosomal dominant pattern of inheritance of IHD. We investigated this region of the MEF2A gene using an Irish family-based study, where affected individuals had early-onset IHD. METHODS: A total of 1494 individuals from 580 families were included (800 discordant sib-pairs and 64 parent-child trios). The Δ7aa region of the MEF2A gene was investigated based on amplicon size. RESULTS: The Δ7aa mutation was not detected in any individual. Variation in the number of CAG (glutamate) and CCG (proline) residues was detected in a nearby region. However, this was not found to be associated with IHD. CONCLUSION: The Δ7aa mutation was not detected in any individual within the study population and is unlikely to play a significant role in the development of IHD in Ireland. Using family-based tests of association the number of tri-nucleotide repeats in a nearby region of the MEF2A gene was not associated with IHD in our study group

Association of war zone–related stress with alterations in limbic gray matter microstructure

IMPORTANCE: Military service members returning from theaters of war are at increased risk for mental illness, but despite high prevalence and substantial individual and societal burden, the underlying pathomechanisms remain largely unknown. Exposure to high levels of emotional stress in theaters of war and mild traumatic brain injury (mTBI) are presumed factors associated with risk for the development of mental disorders. OBJECTIVE: To investigate (1) whether war zone–related stress is associated with microstructural alterations in limbic gray matter (GM) independent of mental disorders common in this population, (2) whether associations between war zone–related stress and limbic GM microstructure are modulated by a history of mTBI, and (3) whether alterations in limbic GM microstructure are associated with neuropsychological functioning. DESIGN, SETTING, AND PARTICIPANTS: This cohort study was part of the TRACTS (Translational Research Center for TBI and Stress Disorders) study, which took place in 2010 to 2014 at the Veterans Affair Rehabilitation Research and Development TBI National Network Research Center. Participants included male veterans (aged 18-65 years) with available diffusion tensor imaging data enrolled in the TRACTS study. Data analysis was performed between December 2017 to September 2021. EXPOSURES: The Deployment Risk and Resilience Inventory (DRRI) was used to measure exposure to war zone–related stress. The Boston Assessment of TBI-Lifetime was used to assess history of mTBI. Stroop Inhibition (Stroop-IN) and Inhibition/Switching (Stroop-IS) Total Error Scaled Scores were used to assess executive or attentional control functions. MAIN OUTCOMES AND MEASURES: Diffusion characteristics (fractional anisotropy of tissue [FA(T)]) of 16 limbic and paralimbic GM regions and measures of functional outcome. RESULTS: Among 384 male veterans recruited, 168 (mean [SD] age, 31.4 [7.4] years) were analyzed. Greater war zone–related stress was associated with lower FA(T) in the cingulate (DRRI-combat left: P = .002, partial r = −0.289; DRRI-combat right: P = .02, partial r = −0.216; DRRI-aftermath left: P = .004, partial r = −0.281; DRRI-aftermath right: P = .02, partial r = −0.219), orbitofrontal (DRRI-combat left medial orbitofrontal cortex: P = .02, partial r = −0.222; DRRI-combat right medial orbitofrontal cortex: P = .005, partial r = −0.256; DRRI-aftermath left medial orbitofrontal cortex: P = .02, partial r = −0.214; DRRI-aftermath right medial orbitofrontal cortex: P = .005, partial r = −0.260; DRRI-aftermath right lateral orbitofrontal cortex: P = .03, partial r = −0.196), and parahippocampal (DRRI-aftermath right: P = .03, partial r = −0.191) gyrus, as well as with higher FA(T) in the amygdala-hippocampus complex (DRRI-combat: P = .005, partial r = 0.254; DRRI-aftermath: P = .02, partial r = 0.223). Lower FA(T) in the cingulate-orbitofrontal gyri was associated with impaired response inhibition (Stroop-IS left cingulate: P < .001, partial r = −0.440; Stroop-IS right cingulate: P < .001, partial r = −0.372; Stroop-IS left medial orbitofrontal cortex: P < .001, partial r = −0.304; Stroop-IS right medial orbitofrontal cortex: P < .001, partial r = −0.340; Stroop-IN left cingulate: P < .001, partial r = −0.421; Stroop-IN right cingulate: P < .001, partial r = −0.300; Stroop-IN left medial orbitofrontal cortex: P = .01, partial r = −0.223; Stroop-IN right medial orbitofrontal cortex: P < .001, partial r = −0.343), whereas higher FA(T) in the mesial temporal regions was associated with improved short-term memory and processing speed (left amygdala-hippocampus complex: P < .001, partial r = −0.574; right amygdala-hippocampus complex: P < .001, partial r = 0.645; short-term memory left amygdala-hippocampus complex: P < .001, partial r = 0.570; short-term memory right amygdala-hippocampus complex: P < .001, partial r = 0.633). A history of mTBI did not modulate the association between war zone–related stress and GM diffusion. CONCLUSIONS AND RELEVANCE: This study revealed an association between war zone–related stress and alteration of limbic GM microstructure, which was associated with cognitive functioning. These results suggest that altered limbic GM microstructure may underlie the deleterious outcomes of war zone–related stress on brain health. Military service members may benefit from early therapeutic interventions after deployment to a war zone

Systematic study of charged-pion and kaon femtoscopy in Au++Au collisions at sNN\sqrt{s_{_{NN}}}=200 GeV

We present a systematic study of charged pion and kaon interferometry in Au$+$Au collisions at $\sqrt{s_{_{NN}}}$=200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal-angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-mass dependence of the oscillations.Comment: 499 authors, 27 pages, 13 figures, and 11 tables. v2 is the version accepted for publication in Phys. Rev. C. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Measurement of higher cumulants of net-charge multiplicity distributions in Au++Au collisions at sNN=7.7−200\sqrt{s_{_{NN}}}=7.7-200 GeV

We report the measurement of cumulants ($C_n, n=1\ldots4$) of the net-charge distributions measured within pseudorapidity ($|\eta|<0.35$) in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=7.7-200$ GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g. $C_1/C_2$, $C_3/C_1$) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmonotonic behavior in the ratios of the cumulants as a function of collision energy. The measured values of $C_1/C_2 = \mu/\sigma^2$ and $C_3/C_1 = S\sigma^3/\mu$ can be directly compared to lattice quantum-chromodynamics calculations and thus allow extraction of both the chemical freeze-out temperature and the baryon chemical potential at each center-of-mass energy.Comment: 512 authors, 8 pages, 4 figures, 1 table. v2 is version accepted for publication in Phys. Rev. C as a Rapid Communication. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Upsilon (1S+2S+3S) production in d+Au and p+p collisions at sqrt(s_NN)=200 GeV and cold-nuclear matter effects

The three Upsilon states, Upsilon(1S+2S+3S), are measured in d+Au and p+p collisions at sqrt(s_NN)=200 GeV and rapidities 1.2<|y|<2.2 by the PHENIX experiment at the Relativistic Heavy-Ion Collider. Cross sections for the inclusive Upsilon(1S+2S+3S) production are obtained. The inclusive yields per binary collision for d+Au collisions relative to those in p+p collisions (R_dAu) are found to be 0.62 +/- 0.26 (stat) +/- 0.13 (syst) in the gold-going direction and 0.91 +/- 0.33 (stat) +/- 0.16 (syst) in the deuteron-going direction. The measured results are compared to a nuclear-shadowing model, EPS09 [JHEP 04, 065 (2009)], combined with a final-state breakup cross section, sigma_br, and compared to lower energy p+A results. We also compare the results to the PHENIX J/psi results [Phys. Rev. Lett. 107, 142301 (2011)]. The rapidity dependence of the observed Upsilon suppression is consistent with lower energy p+A measurements.Comment: 495 authors, 11 pages, 9 figures, 5 tables. Submitted to Phys. Rev. C. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm