Józef Tischner’s epistemology of “political reason” and the “ethics of truth”

Studies in East European Thought - That which connects ethics and epistemology is the concept of truth. The threads concerned with the ethical and epistemological understanding of truth are...     

Pigeons play the percentages: computation of probability in a bird

The ability to compute probability, previously shown in nonverbal infants, apes, and monkeys, was examined in three experiments with pigeons. After responding to individually presented keys in an operant chamber that delivered reinforcement with varying probabilities, pigeons chose between these keys on probe trials. Pigeons strongly preferred a 75% reinforced key over a 25% reinforced key, even when the total number of reinforcers obtained on each key was equated. When both keys delivered 50% reinforcement, pigeons showed indifference between them, even though three times more reinforcers were obtained on one key than on the other. It is suggested that computation of probability may be common to many classes of animals and may be driven by the need to forage successfully for nutritional food items, mates, and areas with a low density of predators.     

Gami-Chunghyuldan ameliorates memory impairment and neurodegeneration induced by intrahippocampal Aβ 1-42 oligomer injection

Soluble oligomeric forms of amyloid beta (AβO) are regarded as a main cause of synaptic and cognitive dysfunction in Alzheimer’s disease (AD) and have been a primary target in the development of drug treatments for AD. The present study utilized a mouse model of AD induced by intrahippocampal injection of AβO (10 μM) to investigate the effects of Gami-Chunghyuldan (GCD), a standardized multi-herbal medicinal formula, on the presentation of memory deficits and neurohistological pathogenesis. GCD (10 and 50 mg/kg/day, 5 days, p.o.) improved AβO-induced memory impairment as well as reduced neuronal cell death, astrogliosis, and microgliosis in the hippocampus. In addition, GCD prevented AβO-triggered synaptic disruption and cholinergic fiber loss. These results suggest that GCD may be useful in the prevention and treatment of AD.     

The effects of rumination and negative cognitive styles on depression: a mediation analysis

Research on cognitive models of depression has identified negative cognitive styles and rumination as risk factors for depression. The present study examined the hypothesis that rumination mediates the effect of negative cognitive styles on depression. Specifically, we evaluated the differential effects of two aspects of rumination, characterized by brooding and reflection, on the relationship between negative cognitive styles and level of depressive symptoms. A total of 115 college students and 38 patients suffering from depressive disorders completed a battery of questionnaires measuring levels of depressive symptoms, brooding, reflection, and negative cognitive styles. The results support the notion that there exist two distinct dimensions of rumination and that, of the two, it is brooding and not reflection that mediates the relationship between negative cognitive styles and depression and contributes to its negative outcomes.