Event-Related Potentials Differentiate Gender-Based Responses to Brands

Despite significant advances in scholarship at the intersection of gender and neuroscience, marketing scholars have failed to capitalize on these developments. This research seeks to fill a gap in the literature by examining brain-related responses to brands as a function of gender using event-related potentials (ERPs), which employs time-locked electroencephalographic (EEG) data. Thirty-three participants (17 female) made evaluations of clothing brands and clothing articles, individually and combined, while their preferences and brain-related data were recorded. Results reveal a gender-based dissociation in the time course of product-brand evaluations and offer new insights for gender selectivity theory

Revisiting the Role of the Amygdala in Posttraumatic Stress Disorder

Over the past 20 years, the reactivity of amygdala to emotive stimuli has been explored by emerging neuroimaging techniques in an effort to understand the role of amygdala in the pathophysiology of posttraumatic stress disorder (PTSD). A fear neurocircuitry model, whereby the amygdala is hyperactive due to poor top-down control from the anterior cingulate and ventromedial prefrontal cortices, has been supported by numerous experimental studies and meta-analyses. However, this model has not always been upheld by experimental data and clinical observations. In particular, many neuroimaging studies find that the amygdala fails to activate in response to negative stimuli in individuals with PTSD. Several technical and design issues may explain disparate results regarding amygdala reactivity in PTSD. However, biological and symptom-based factors emerge as possible mediators of amygdala function in PTSD, leading to the conclusion that symptoms of emotional disengagement and dissociation are associated with amygdala hyporeactivity, and symptoms of hypervigilance/hyperarousal and problems with fear conditioning and extinction are reflected by amygdala hyperactivity. Therefore, treatment of PTSD should take into account the nature of amygdala dysfunction in the individual to optimize treatment outcomes

Motor, not visual, encoding of potential reach targets

SummaryWe often encounter situations in which there are multiple potential targets for action, as when, for example, we hear the request “could you pass the …” at the dinner table. It has recently been shown that, in such situations, activity in sensorimotor brain areas represents competing reach targets in parallel prior to deciding between, and then reaching towards, one of these targets [1]. One intriguing possibility, consistent with the influential notion of action ‘affordances’ [2], is that this activity reflects movement plans towards each potential target [3]. However, an equally plausible explanation is that this activity reflects an encoding of the visual properties of the potential targets (for example, their locations or directions), prior to any target being selected and the associated movement plan being formed. Notably, previous work showing spatial averaging behaviour during reaching, in which initial movements are biased towards the midpoint of the spatial distribution of potential targets [4–6], remains equally equivocal concerning the motor versus visual encoding of reach targets. Here, using a rapid reaching task that disentangles these two competing accounts, we show that reach averaging behaviour reflects the parallel encoding of multiple competing motor plans. This provides direct evidence for theories proposing that the brain prepares multiple available movements before selecting between them [3]

The Oxford-Dartmouth Thirty Degree Survey II: Clustering of Bright Lyman Break Galaxies - Strong Luminosity Dependent Bias at z=4

We present measurements of the clustering properties of bright ($L>L_{*}$) z$\sim$4 Lyman Break Galaxies (LBGs) selected from the Oxford-Dartmouth Thirty Degree Survey (ODT). We describe techniques used to select and evaluate our candidates and calculate the angular correlation function which we find best fitted by a power law, $\omega(\theta)=A_{w}\theta^{-\beta}$ with $A_{w}=15.4$ (with $\theta$ in arcseconds), using a constrained slope of $\beta=0.8$. Using a redshift distribution consistent with photometric models, we deproject this correlation function and find a comoving $r_{0}=11.4_{-1.9}^{+1.7}$ h$_{100}^{-1}$ Mpc in a $\Omega_m=0.3$ flat $\Lambda$ cosmology for $i_{AB}\leq24.5$. This corresponds to a linear bias value of $b=8.1_{-2.6}^{+2.0}$ (assuming $\sigma_{8}=0.9$). These data show a significantly larger $r_{0}$ and $b$ than previous studies at $z\sim4$. We interpret this as evidence that the brightest LBGs have a larger bias than fainter ones, indicating a strong luminosity dependence for the measured bias of an LBG sample. Comparing this against recent results in the literature at fainter (sub-$L_{*}$) limiting magnitudes, and with simple models describing the relationship between LBGs and dark matter haloes, we discuss the implications on the implied environments and nature of LBGs. It seems that the brightest LBGs (in contrast with the majority sub-$L_{*}$ population), have clustering properties, and host dark matter halo masses, that are consistent with them being progenitors of the most massive galaxies today.Comment: Accepted for Publication in MNRAS. 15 Pages, 13 Figure

Sussing merger trees: the Merger Trees Comparison Project

Merger trees follow the growth and merger of dark-matter haloes over cosmic history. As well as giving important insights into the growth of cosmic structure in their own right, they provide an essential backbone to semi-analytic models of galaxy formation. This paper is the first in a series to arise from the Sussing Merger Trees Workshop in which 10 different tree-building algorithms were applied to the same set of halo catalogues and their results compared. Although many of these codes were similar in nature, all algorithms produced distinct results. Our main conclusions are that a useful merger-tree code should possess the following features: (i) the use of particle IDs to match haloes between snapshots; (ii) the ability to skip at least one, and preferably more, snapshots in order to recover subhaloes that are temporarily lost during merging; (iii) the ability to cope with (and ideally smooth out) large, temporary fluctuations in halo mass. Finally, to enable different groups to communicate effectively, we defined a common terminology that we used when discussing merger trees and we encourage others to adopt the same language. We also specified a minimal output format to record the results

Current Understanding of Biomarkers in Post Traumatic Stress Disorder and Mild Traumatic Brain Injury: A Systematic Review and Implications for Research and Treatment

For nearly 100 years, it was erroneously believed that the loss of consciousness and/or the altered mental status associated with a mild traumatic brain injury (mTBI) offered protection from the development of posttraumatic stress disorder (PTSD). However, it is now accepted that it is possible for PTSD to result from mTBI, and that the co-occurrence of these two conditions creates a more difficult condition to treat and worsens prognosis. In addition, it is known that the symptomology associated with PTSD and mTBI have a great deal of overlap, complicating diagnoses. The objective of this chapter is to review the current state of biomarkers aimed at diagnosing comorbid mTBI and PTSD that are useful on a single-patient basis and are not reliant on self-report or arduous interviews. Further, implications for future research and treatment are discussed

Clinicopathological evaluation of chronic traumatic encephalopathy in players of American football

IMPORTANCE: Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). OBJECTIVE: To determine the neuropathological and clinical features of deceased football players with CTE. DESIGN, SETTING, AND PARTICIPANTS: Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. EXPOSURES: Participation in American football at any level of play. MAIN OUTCOMES AND MEASURES: Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. RESULTS: Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre–high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89%) had behavioral or mood symptoms or both, 80 (95%) had cognitive symptoms, and 71 (85%) had signs of dementia. CONCLUSIONS AND RELEVANCE: In a convenience sample of deceased football players who donated their brains for research, a high proportion had neuropathological evidence of CTE, suggesting that CTE may be related to prior participation in football.This study received support from NINDS (grants U01 NS086659, R01 NS078337, R56 NS078337, U01 NS093334, and F32 NS096803), the National Institute on Aging (grants K23 AG046377, P30AG13846 and supplement 0572063345-5, R01 AG1649), the US Department of Defense (grant W81XWH-13-2-0064), the US Department of Veterans Affairs (I01 CX001038), the Veterans Affairs Biorepository (CSP 501), the Veterans Affairs Rehabilitation Research and Development Traumatic Brain Injury Center of Excellence (grant B6796-C), the Department of Defense Peer Reviewed Alzheimer’s Research Program (grant 13267017), the National Operating Committee on Standards for Athletic Equipment, the Alzheimer’s Association (grants NIRG-15-362697 and NIRG-305779), the Concussion Legacy Foundation, the Andlinger Family Foundation, the WWE, and the NFL

UV-optical colors as probes of early-type galaxy evolution

We have studied ∼2100 early-type galaxies in the SDSS DR3 which have been detected by the GALEX Medium Imaging Survey (MIS), in the redshift range O <z <0.1.1. Combining GALEXUV photometry with corollary optical data from the SDSS, we find that, at a 95% confidence level, at least ∼30% of galaxies in this sample have UV to optical colors consistent with some recent star formation within the last Gyr. In particular, galaxies with an NUV - r color less than 5.5 are very likely to have experienced such recent star formation, taking into account the possibility of a contribution to NUV flux from the UV upturn phenomenon. We find quantitative agreement between the observations and the predictions of a semianalytical ACDM hierarchical merger model and deduce that early-type galaxies in the redshift range 0 <z <0.11 have ∼ 1 % -3 % of their stellar mass in stars less than 1 Gyr old. The average age of this recently formed population is ∼300-500 Myr. We also find that "monolithically" evolving galaxies, where recent star formation can be driven solely by recycled gas from stellar mass loss, cannot exhibit the blue colors (NUV - r <5.5) seen in a significant fraction (∼30%) of our observed sample.Peer reviewe

The Ages, Metallicities and Alpha Element Enhancements of Globular Clusters in the Elliptical NGC 5128: A Homogeneous Spectroscopic Study with Gemini/GMOS

We present new integrated light spectroscopy of globular clusters (GCs) in NGC 5128 in order to measure radial velocities and derive ages, metallicities, and alpha-element abundance ratios. Using Gemini-S 8-m/GMOS, we obtained spectroscopy in the range of ~3400-5700 AA for 72 GCs with S/N > 30 /AA and we have also discovered 35 new GCs within NGC 5128 from our radial velocity measurements. We measured and compared the Lick indices from HdeltaA through Fe5406 with the single stellar population (SSP) models of Thomas et al.(2003,2004). We also measure Lick indices for 41 Milky Way GCs from Puzia et al. (2002) and Schiavon et al. (2005) with the same methodology for direct comparison. Our results show that 68% of the NGC 5128 GCs have old ages (> 8 Gyr), 14% have intermediate ages (5-8 Gyr), and 18% have young ages (< 5 Gyr). However, when we look at the metallicity of the GCs as a function of age, we find 92% of metal-poor GCs and 56% of metal-rich GCs in NGC 5128 have ages > 8 Gyr, indicating that the majority of both metallicity subpopulations of GCs formed early, with a significant population of young and metal-rich GCs forming later. Our metallicity distribution function generated directly from spectroscopic Lick indices is clearly bimodal, as is the color distribution of the same set of GCs. Thus the metallicity bimodality is real and not an artifact of the color to metallicity conversion. The [alpha/Fe] values are supersolar with a mean value of 0.14pm0.04, indicating a fast formation timescale. However, the GCs in NGC 5128 are not as [alpha/Fe] enhanced as the Milky Way GCs also examined in this study. Our results support a rapid, early formation of the GC system in NGC 5128, with subsequent major accretion and/or GC and star forming events in more recent times (abridged).Comment: Accepted to The Astrophysical Journal, 36 pages, 14 figures, 7 table

Galaxy clustering in the NEWFIRM Medium Band Survey: the relationship between stellar mass and dark matter halo mass at 1 < z < 2

We present an analysis of the clustering of galaxies as a function of their stellar mass at 1 < z < 2 using data from the NEWFIRM Medium Band Survey (NMBS). The precise photometric redshifts and stellar masses that the NMBS produces allows us to define a series of mass limited samples of galaxies more massive than 0.7, 1 and 3x10^10 Msun in redshift intervals centered on z = 1.1, 1.5 and 1.9 respectively. In each redshift interval we show that there exists a strong dependence of clustering strength on the stellar mass limit of the sample, with more massive galaxies showing a higher clustering amplitude on all scales. We further interpret our clustering measurements in the LCDM cosmological context using the halo model of galaxy clustering. We show that the typical halo mass of central and satellite galaxies increases with stellar mass, whereas the satellite fraction decreases with stellar mass, qualitatively the same as is seen at z < 1. We see little evidence of any redshift dependence in the stellar mass-to-halo mass relationship over our narrow redshift range. However, when we compare with similar measurements at z~0, we see clear evidence for a change in this relation. If we assume a universal baryon fraction, the ratio of stellar mass to halo mass reveals the fraction of baryons that have been converted to stars. We see that the peak in this star formation efficiency for central galaxies shifts to higher halo masses at higher redshift, moving from ~7x10^11 Msun at z~0 to ~3x10^12 Msun at z~1.5, revealing evidence of `halo downsizing'. Finally we show that for highly biased galaxy populations at z > 1 there may be a discrepancy between the measured space density and clustering and that predicted by the halo model. This could imply that there is a problem with one or more ingredients of the halo model at these redshifts, for instance the halo bias relation or the halo profile.Comment: Accepted for publication in ApJ. Correction made to typo in halo masses in conclusion