Neurocognitive disorders, among which Alzheimer’s disease (AD), have become one of the major causes of death in developed countries. No effective disease-modifying therapy is available, possibly because current treatments are administered too late to still be able to intervene in the disease progress. AD is characterized by a gradual onset with subclinical neurobiological and behavioral changes that precede diagnosis with years to even decades. The earlier the diagnosis, the earlier potential treatments can be tested and started. Mouse models are valuable to study the possible causes underlying early phases of neuropathology and their reflection in behavior and other biomarkers, to help improve preclinical detection and diagnosis of AD. Here, we assessed cognitive functioning and social behavior in transgenic mice expressing tau pathology only (Tau-P301L) or a combination of amyloid and tau pathology [amyloid precursor protein (APP)-V717I × Tau-P301L]. The mice were subjected to a variety of behavioral tasks at an age of 3–6 months, i.e., at an early phase of their AD-like pathology. We hypothesized that compared to age-matched wild-type controls, transgenic mice would show specific impairments in both cognitive and non-cognitive tasks. In line with our expectations, transgenic mice showed decreased cognitive flexibility in the Morris water maze, decreased exploratory behavior, decreased performance in a nesting task, and increased anxiety-like behavior. In accordance with the amyloid-cascade hypothesis, some of the behavioral measures showed more severe deficits in APP-V717I × Tau-P301L compared to Tau-P301L mice, indicating an exacerbation of disease processes due to the co-occurrence of amyloid and tau pathology. Our study supports the use of behavioral markers as early indicators of ongoing AD pathology during the preclinical phase.

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Numerous examples of meaningful inter-individual differences in visual processing have been documented in low-and high-level vision. For mid-level vision or perceptual organization, vision scientists have only recently started to study the inter-individual differences structure. In this study, we focus on orientation and proximity as emergent features and combine a quantitative information processing approach with an individual differences approach. We first replicated a previous study with a similar question in a set of 52 observers. That is, observers showed higher processing capacity for detecting a change in a stimulus configuration when the emergent features orientation or proximity were changed. Next, we asked whether individual differences processing capacities were similar across emergent features. The capacity to detect any type of change correlated moderately across individuals, whereas the capacity to detect changes in either emergent feature alone was not strongly correlated. This indicates that there is no general sensitivity to emergent features and that observers can be good at detecting orientation changes whilst being poor at detecting proximity changes (and vice versa). An additional exploratory multivariate analysis of the data revealed that response times and accuracies correlated strongly within each emergent feature. Moreover, specific factors related to change detection and inward displacements were observed, revealing consistent individual differences in our data. We discuss the results in the context of the literature on individual differences in vision where both specific, fragmented factors as well as broad, general factors have been reported.

Exercise has a beneficial effect on mental health and cognitive functioning, but the exact underlying mechanisms remain largely unknown. In this review, we focus on the effect of exercise on hippocampal pattern separation, which is a key component of episodic memory. Research has associated exercise with improvements in pattern separation. We propose an integrated framework mechanistically explaining this relationship. The framework is divided into three pathways, describing the pro-neuroplastic, anti-inflammatory and hormonal effects of exercise. The pathways are heavily intertwined and may result in functional and structural changes in the hippocampus. These changes can ultimately affect pattern separation through direct and indirect connections. The proposed framework might guide future research on the effect of exercise on pattern separation in the hippocampus.

Introduction: Childhood adversity may result in a negative expectation of future interactions with others, also referred to as ‘threat anticipation’. It may also negatively impact on identity development, which subsequently may influence how individuals deal with their environment. Here, we examine the hypotheses that 1) identity development is associated with threat anticipation, and 2) that identity confusion, in the presence of childhood adversity, has a synergistic effect on the development of threat anticipation. Methods: 1913 adolescents from the general population (mean age = 13.8 years, SD = 1.86, range = 11-20) completed self-report questionnaires assessing exposure to childhood adversity, identity development and threat anticipation. Results: Identity development was significantly associated with threat anticipation in the expected direction: identity synthesis was associated with reduced anticipation of threat (β = -.0013, p < .001), whereas identity confusion was association with increased threat anticipation (β = .0017, p < .001). Furthermore, childhood adversity was positively associated with threat anticipation (β = .0018, p < .001). However, no evidence for an interaction effect of identity on the association between childhood adversity and threat anticipation was found.Conclusion: The current study illustrates the importance of exposure to childhood adversity and identity development for the anticipation of threat. Identity development however did not moderate the association between childhood adversity and threat anticipation, suggesting childhood adversity and identity development have an additive rather than synergistic effect on threat anticipation. Further research is needed to clarify how both factors influence each other within a developmental framework.