Cerebrospinal fluid concentrations of biogenic amines and corticotropin-releasing factor in adolescent non-human primates as a function of the timing of adverse early rearing

Adolescent bonnet macaques nursed as infants by mothers facing unpredictable requirements for food procurement (variable foraging demand, VFD) display persistent neurobiological disturbances. This study examined the long-term neurochemical and behavioral effects of adverse rearing initiated later in infancy than in previous cohorts of subjects to test the hypothesis that the timing of an early adverse experience would influence patterns of biobehavioral outcome. Cisternal cerebrospinal fluid (CSF) monoamine and corticotropin-releasing factor (CRF) concentrations were obtained from 20 bonnet macaques (11 VFD-reared and 9 normally reared controls) approximately 2 years after the end of differential rearing. VFD-reared primates displayed on multiple samplings significantly lower CSF CRF concentrations and higher CSF 5-hydroxyindoleacetic acid (5-HIAA) concentration compared to controls. In the VFD-reared, significant inverse correlations between CRF and all three monoamines were found (5-HIAA, 3-methoxy-4-hydroxyphenethyleneglycol and homovanillic acid), most prominently for 5-HIAA. In controls, but not VFD-reared subjects, CSF CRF was positively correlated with changes in "gregariousness" upon presentation of a fear stimulus. VFD-reared subjects displayed greater baseline hierarchical engagement than controls. In contrast to prior findings, in which rearing under VFD conditions at an earlier age led to increased CSF CRF compared with controls, CSF CRF was lower after later exposure to VFD rearing than in controls. Thus, the timing of exposure to VFD conditions early in life evidently determines whether CSF CRF was found to be elevated or decreased, within the context of increased serotonin metabolism, during the course of primate maturation.     

Reduced delayed-rectifier K+ current in the learning mutant rutabaga

In the Drosophila mutant rutabaga, short-term memory is deficient and intracellular cyclic adenosine monophosphate (cAMP) concentration is reduced. We characterized the delayed-rectifier potassium current (IK_DR) in rutabaga as compared with the wild-type. The conventional whole-cell patch-clamp technique was applied to cultured Drosophila neurons derived from embryonic neuroblasts. IK_DR was smaller in rutabaga (368±11 pA) than in wild-type (541±14 pA) neurons, measured in a Ca²⁺-free solution. IK_DR was clearly activated at ~0 mV in the two genotypes. IK_DR typically reached its peak within 10–20 msec after the start of the pulse (60 mV). There was no difference in inactivation of IK_DR for wild-type (14±3%) and rutabaga (19±3%). After application of 10 mM TEA, in wild-type, IK_DR was reduced by 46±5%, whereas in rutabaga, IK_DR was reduced by 28±3%. Our results suggest that IK_DR is carried by two different types of channels, one which is TEA-sensitive, whereas the other is TEA-insensitive. Apparently, the TEA-sensitive channel is less expressed in rutabaga neurons than in wild-type neurons. Conceivably, altered neuronal excitability in the rutabaga mutant could disrupt the processing of neural signals necessary for learning and memory.     

Glutamate-hypothalamic-pituitary-adrenal axis interactions: implications for mood and anxiety disorders

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is a pathologic feature of certain mood and anxiety disorders that results in the increased production and secretion of corticotropin-releasing factor. There is increasing preclinical evidence that glutamate, an excitatory amino acid, plays an important role in the regulation of the HPA axis. Activation of glutamatergic projections to limbic structures such as the amygdala and brainstem structures such as the nucleus tractus solitarius is implicated in the stress response. There are laboratory and clinical suggestions that glutamatergic N-methyl-D-aspartate (NMDA) receptor antagonists function as antidepressants, and that chronic antidepressant treatments have a significant impact on NMDA receptor function. Clinical investigations of glutamate antagonists in patients with mood and anxiety disorders are in their infancy, with a few reports suggesting the presence of mood-elevating properties. Ultimately, HPA axis modulators, serotonin-enhancing agents, and glutamate antagonists might serve to increase neurotropic factors in key brain regions for affective and anxiety regulation, providing a putative final common pathway.     

Mitigation system threat partially mediates the effects of right‐wing ideologies on climate change beliefs

Research consistently shows that right‐wing ideological adherents are more likely to deny climate change. However, less is known about how right‐wing ideological subtypes are uniquely related to climate change denial, as well as what explains these relationships. This study examines whether threat to the socioeconomic system in the form of climate change mitigation policies, referred to as Climate Change Mitigation Threat (CCMT), mediates the relationships between Right‐Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO) subtypes and four forms of climate change denial (existence denial, human cause denial, impact denial and climate science denial). U.S. participants (N = 334; M_age = 34.70, SD = 5.98) were recruited via Amazon MTurk. When shared variance in the predictors was accounted for, we found that: (a) Conventionalism (RWA‐C) positively predicted all forms of climate change denial; (b) Dominance (SDO‐D) positively predicted existence denial; (c) Anti‐Egalitarianism (SDO‐E) positively predicted both human cause and impact denial; and (d) Aggression (RWA‐A) negatively predicted existence denial. All significant direct relationships were partially mediated by CCMT, except for the direct paths between SDO‐D and existence denial, and RWA‐A and existence denial. These findings suggest that right‐wing adherents who conform to societal norms and prefer unequal social systems may deny climate change partly due to a perception that mitigation strategies proposed to combat climate change threaten the existing socioeconomic system.     

Human trafficking: factors that influence willingness to combat the issue

Human trafficking involves severe violations of human rights and social action is required to combat it. Past research has identified emotional reactions to victims of trafficking, as well as the perceived cost and efficacy of actions, as significant predictors of willingness to get involved. We surveyed 216 Australians (70% female) to assess their perceptions of sex and labor trafficking and actions to reduce them. Results demonstrated that women reported greater personal distress (but not empathy) for victims than men, which was associated with greater willingness to take action. Women also perceived available actions to be more efficacious than men, which predicted willingness, while perceived cost of actions did not. Implications for promoting social action to reduce human trafficking are discussed.     

A Global Happiness Scale for Measuring Wellbeing: A Test of Immunity Against Hedonism

Wellbeing is gaining acceptance as an indicator of social and economic progress by many governments and agencies. As such the scientific community is actively engaging in developing scales to gauge wellbeing at a community and national level. A common approach used comprises of asking subjects a single question on happiness. A major issue with single questions is the difficulty to establish reliability. Recognising this issue, researchers have developed an itemised Global Happiness Scale (GHS) comprising of four items. GHS is reported to have satisfactory reliability and convergent validity and the scale has been translated into a number of different languages. However to ensure GHS is measuring happiness at a global level, that is measuring eudaimonic happiness, it is necessary to ensure it is immune to hedonic happiness. GHS had not been previously subjected to a hedonic immunity test, which the current study addressed. This paper reports and discusses the reliability and hedonic immunity of GHS.     

The Effect of Non-Stroke Cardiovascular Disease States on Risk for Cognitive Decline and Dementia: A Systematic and Meta-Analytic Review

Cardiovascular disease is associated with increased risk for cognitive decline and dementia, but it is unclear whether this risk varies across disease states or occurs in the absence of symptomatic stroke. To examine the evidence of increased risk for cognitive decline and dementia following non-stroke cardiovascular disease we conducted two independent meta-analyses in accordance with PRISMA guidelines. The first review examined cardiovascular diagnoses (atrial fibrillation, congestive heart failure, periphery artery disease and myocardial infarction) while the second review assessed the impact of atherosclerotic burden (as indicated by degree of stenosis, calcification score, plaque morphology or number of plaques). Studies eligible for review longitudinally assessed risk for clinically significant cognitive decline and/or dementia and excluded stroke and cognitive impairment at baseline. Summary statistics were computed via the inverse variance weighted method, utilising Cox Proportional Hazards data (Hazard Ratios, HR). Both atrial fibrillation (n = 5, HR = 1.26, 95% CI [1.12, 1.43]) and severe atherosclerosis (n = 4, HR = 1.59, 95% CI [1.12, 2.26]) emerged as significant risk factors for cognitive decline and/or dementia. A small set of studies reviewed, insufficient for meta-analysis, examining congestive heart failure, peripheral artery disease and myocardial infarction suggested that these conditions may also be associated with an increased risk of cognitive decline/dementia. In the absence of stroke, patients with atrial fibrillation or generalised atherosclerosis are at heightened risk for cognitive deterioration. Nonetheless, this paper highlights the need for methodologically rigorous and prospective investigation of the relationship between CVD and dementia.     

Enhancement of phonological memory following transcranial magnetic stimulation (TMS)

Phonologically similar items (mell, rell, gell) are more difficult to remember than dissimilar items (shen, floy, stap), likely because of mutual interference of the items in the phonological store. Low-frequency transcranial magnetic stimulation (TMS), guided by functional magnetic resonance imaging (fMRI) was used to disrupt this phonological confusion by stimulation of the left inferior parietal (LIP) lobule. Subjects received TMS or placebo stimulation while remembering sets of phonologically similar or dissimilar pseudo-words. Consistent with behavioral performance of patients with neurological damage, memory for phonologically similar, but not dissimilar, items was enhanced following TMS relative to placebo stimulation. Stimulation of a control region of the brain did not produce any changes in memory performance. These results provide new insights into how the brain processes verbal information by establishing the necessity of the inferior parietal region for optimal phonological storage. A mechanism is proposed for how TMS reduces phonological confusion and leads to facilitation of phonological memory.