Dietary ethyl-eicosapentaenoic acid but not soybean oil reverses central interleukin-1-induced changes in behavior, corticosterone and immune response in rats

Omega (n)-3 and n-6 fatty acids are important membrane components of neurons and immune cells, and related to psychiatric and inflammatory diseases. Increased ratio of n-6/n-3 in the blood has been reported in depressed patients and in students following stress exposure. The n-3 fatty acid, eicosapentaenoic acid (ethyl-EPA) suppresses inflammation and has antidepressant properties. Interleukin (IL)-1beta can stimulate corticosterone secretion, induce anxiety and stress-like behavior and inflammatory responses. This study was to evaluate the effect of diets enriched with coconut oil, ethyl-EPA and soybean oil on central IL-1beta induced stress and anxiety-like behavior, induced changes in the concentration of prostaglandin (PG) E2 and corticosterone and the release of IL-10. Groups of rats were fed with either 5% coconut oil (as control diet), 0.2% EPA with 4.8% coconut oil or 1% EPA with 4% coconut oil and 5% soybean oil for 7 weeks. The central administration of IL-1beta induced sickness, stress and anxiety-like behavior as indicated by a reduction in body weight, decreased time spent, and the number of entries, into the open arms of the elevated plus maze and decreased exploration and entry into the central zone of the "open field" apparatus. IL-1beta also increased PGE2 and corticosterone concentrations and decreased the release of IL-10 from leucocytes. Food enriched with ethyl-EPA but not soybean oil, significantly attenuated most of these changes. These results demonstrate that ethyl-EPA has anti-inflammatory, anti-stress and anti-anxiety effects in rats.     

The Gladiator Sparrow: ethical issues in behavioral research on captive populations of wild animals: a case study with commentaries exploring ethical issues and research on wild animal populations

This case involves invasive research on captive wild populations of birds to study aggressive animal behavior. The case and associated commentaries raise and examine fundamental issues, whether and under what conditions, such research is ethically justified when the research has no expected, direct application to the human species; the moral status of animals and how one balances concern for the animal's interests against the value of gains in scientific knowledge. They also emphasize the issue of the importance of a thorough literature search to ensure appropriate research design and experimental design to minimize animal suffering. It raises the issue of circumstances in which such research should be modified or terminated.     

Effects of grouping and attention on the perception of causality

Beyond perceiving patterns of motion in simple dynamic displays, we can also perceive higher level properties, such as causality, as when we see one object collide with another object. Although causality is a seemingly high-level property, its perception--like the perception of faces or speech--often appears to be automatic, irresistible, and driven by highly constrained and stimulus-driven rules. Here, in an exploration of such rules, we demonstrate that perceptual grouping and attention can influence the both perception of causality in ambiguous displays. We first report several types of grouping effects, based on connectedness, proximity, and common motion. We further suggest that such grouping effects are mediated by the allocation of attention, and we directly demonstrate that causal perception can be strengthened or attenuated on the basis of where observers are attending, independent of fixation. Like Michotte, we find that the perception of causality is mediated by strict visual rules. Beyond Michotte, we find that these rules operate not only over discrete objects, but also over perceptual groups, constrained by the allocation of attention.     

Autobiographical memory and the self in time: brain lesion effects, functional neuroanatomy, and lifespan development

Autobiographical remembering reflects an advanced state of consciousness that mediates awareness of the self as continuous across time. In naturalistic autobiographical memory, self-aware recollection of temporally and spatially specific episodes and generic factual information (both public and personal) operate in tandem. Evidence from both laboratory and real-life studies, however, suggests that these two processes can be dissociated. This paper reviews aging, lesion, and functional neuroimaging research on the anatomical substrates of autobiographical memory processes using a new measure, the Autobiographical Interview, and prospective collection of autobiographical material. Results indicate that autobiographical recollection is mediated by a distributed fronto-temporo-parietal system, with the anteromedial prefrontal cortex positioned to integrate sensory information with self-specific information. The emergence of autobiographical recollection at around age four coincides with the timing of prefrontal regressive cortical and progressive white matter changes that may support the development of this high-level capacity.     

Group therapy for depressed elderly women

We describe and evaluate a group therapy program targeting depression among elderly residents (N=303) of subsidized high-rise apartments in Nashville, TN. This eclectic program was comprised of 12 sessions (a total of 24 hours) that included modules on exercise and preventive health behaviors, cognitive and re-motivation therapy, reminiscence and grief therapy, and social skills development. Our multivariate regression analyses of pre-post measures using the Geriatric Depression Scale (GDS) showed that the effects of the group therapy varied by race, age, and level of initial depression among the participants. The program was effective in reducing depression, but only among Caucasian women who reported at least moderate depression prior to the program, and it yielded greater benefits for women between 55 and 75 years of age.     

Divide and conquer: how object files adapt when a persisting object splits into two

Coherent visual experience requires not only segmenting incoming visual input into a structured scene of objects, but also binding discrete views of objects into dynamic representations that persist across time and motion. However, surprisingly little work has explored the principles that guide the construction and maintenance of such persisting object representations. What causes a part of the visual field to be treated as the same object over time? In the cognitive development literature, a key principle of object persistence is cohesion: An object must always maintain a single bounded contour. Here we demonstrate for the first time that mechanisms of adult midlevel vision are affected by cohesion violations. Using the object-file framework, we tested whether object-specific preview benefits-a hallmark of persisting object representations-are obtained for dynamic objects that split into two during their motion. We found that these preview benefits do not fully persist through such cohesion violations without incurring significant performance costs. These results illustrate how cohesion is employed as a constraint that guides the maintenance of object representations in adult midlevel vision.