Aggression in Tilapia affects immunocompetent leucocytes

Social interactions are typical behavioral patterns serving to regulate life in a group. These interactions may develop into aggression, which causes stress in the defeated animal. We used Tilapia, a commercially important fish which is aggressive, to examine how this behavior affects them and whether it induces alterations in leucocytes. Compared to dominant fish, subordinate ones had elevated glucose levels and hemolytic blood sera. In addition, cells from blood and pronephros of subordinates, when compared to dominant fish, showed qualitative changes characterized by granulocytosis and lymphopenia. Furthermore, leucocytes revealed cytoplasmic and karyoplasmic vacuolation, indicating cellular disintegration. These morphological alterations were also accompanied by impaired leukocyte function and thus may increase susceptibility to diseases and neoplasia.     

Super-Recognisers show an advantage for other race face identification

The accurate identification of an unfamiliar individual from a face photo is a critical factor in several applied situations (e.g., border control). Despite this, matching faces to photographic ID is highly prone to error. In lieu of effective training measures, which could reduce face matching errors, the selection of “super-recognisers” (SRs) provides the most promising route to combat misidentification or fraud. However, to date, super-recognition has been defined and tested using almost exclusively “own-race” face memory and matching tests. Here, across three studies, we test Caucasian participants' performance on own- and other-race face identification tasks (GFMT, MFMT, CFMT+, EFMT, CFMT-Chinese). Our findings show that compared to controls, high-performing typical recognisers (Studies 1 and 2) and SRs (Study 3) show superior performance on both the own- and other-race tests. These findings suggest that recruiting SRs in ethnically diverse applied settings could be advantageous.     

A neural model of hippocampal–striatal interactions in associative learning and transfer generalization in various neurological and psychiatric patients

Building on our previous neurocomputational models of basal ganglia and hippocampal region function (and their modulation by dopamine and acetylcholine, respectively), we show here how an integration of these models can inform our understanding of the interaction between the basal ganglia and hippocampal region in associative learning and transfer generalization across various patient populations. As a common test bed for exploring interactions between these brain regions and neuromodulators, we focus on the acquired equivalence task, an associative learning paradigm in which stimuli that have been associated with the same outcome acquire a functional similarity such that subsequent generalization between these stimuli increases. This task has been used to test cognitive dysfunction in various patient populations with damages to the hippocampal region and basal ganglia, including studies of patients with Parkinson’s disease (PD), schizophrenia, basal forebrain amnesia, and hippocampal atrophy. Simulation results show that damage to the hippocampal region—as in patients with hippocampal atrophy (HA), hypoxia, mild Alzheimer’s (AD), or schizophrenia—leads to intact associative learning but impaired transfer generalization performance. Moreover, the model demonstrates how PD and anterior communicating artery (ACoA) aneurysm—two very different brain disorders that affect different neural mechanisms—can have similar effects on acquired equivalence performance. In particular, the model shows that simulating a loss of dopamine function in the basal ganglia module (as in PD) leads to slow acquisition learning but intact transfer generalization. Similarly, the model shows that simulating the loss of acetylcholine in the hippocampal region (as in ACoA aneurysm) also results in slower acquisition learning. We argue from this that changes in associative learning of stimulus–action pathways (in the basal ganglia) or changes in the learning of stimulus representations (in the hippocampal region) can have similar functional effects.     

Students' daily emotions in the classroom: Intra‐individual variability and appraisal correlates

Background. Recent literature on emotions in education has shown that competence‐ and value‐related beliefs are important sources of students' emotions; nevertheless, the role of these antecedents in students' daily functioning in the classroom is not yet well‐known. More importantly, to date we know little about intra‐individual variability in students' daily emotions. Aims. The objectives of the study were (1) to examine within‐student variability in emotional experiences and (2) to investigate how competence and value appraisals are associated with emotions. It was hypothesized that emotions would show substantial within‐student variability and that there would be within‐person associations between competence and value appraisals and the emotions. Sample(s). The sample consisted of 120 grade 7 students (52%, girls) in 5 randomly selected classrooms in a secondary school. Method. A diary method was used to acquire daily process variables of emotions and appraisals. Daily emotions and daily appraisals were assessed using items adapted from existing measures. Results. Multi‐level modelling was used to test the hypotheses. As predicted, the within‐person variability in emotional states accounted for between 41% (for pride) and 70% (for anxiety) of total variability in the emotional states. Also as hypothesized, the appraisals were generally associated with the emotions. Conclusions. The within‐student variability in emotions and appraisals clearly demonstrates the adaptability of students with respect to situational affordances and constraints in their everyday classroom experiences. The significant covariations between the appraisals and emotions suggest that within‐student variability in emotions is systematic.