Changes in cognitive performance during a 216 kilometer, extreme endurance footrace: a descriptive and prospective study

Two subjects participated in a 216 km ultramarathon with outside temperatures above 50 degrees C while several physiological and psychological parameters (cognitive performance assessed by a mental calculation task and an attentional task, subjective bodily experience, and lactate level) were evaluated throughout the race. Severe stress from dehydration, sleep deprivation, and total physical exhaustion are combined in a unique manner, allowing evaluation of their effects in a range far outside that obtainable in a laboratory setting. During the race the subjects answered a questionnaire about their actual bodily experiences, underwent 8 medical examinations, and performed two cognitive tests approximately every 35 kilometers. Analysis showed cognitive performance did not decrease steadily in a simple and gradual way but reached a peak in the morning of Day 2 after a short sleeping period and then decreased. In the early morning of Day 3, in general cognitive performance exhibited the worst results but increased differentially between the subjects again in the last test 1 km before the finish line.     

The effects of prior knowledge on children's memory and suggestibility

In this study, 5- and 6-year-olds were read a story and asked to recall its details. Two independent factors-prestory knowledge and poststory suggestions-were crossed to examine the effects on children's story recall. The results indicated that prestory social knowledge about the story protagonist as well as academic knowledge relating to the content of the story influenced the accuracy of children's recall immediately after the story presentation. Following the suggestive interview, children reported interviewer-provided social and academic misinformation to a greater extent when the misinformation was consistent with their prior knowledge. In contrast, children were more likely to refute misinformation that contradicted their academic knowledge. These findings are discussed in terms of the mechanisms underlying the knowledge-memory and knowledge-suggestibility linkages.     

Stroop dilution but not word-processing dilution: evidence for attention capture

Stroop dilution refers to the observation that the impact of a color word on the naming of a color bar is reduced if another word-like object is displayed simultaneously. Recently, Brown, Roos-Gilbert, and Carr (1995) concluded that Stroop dilution is due to early-visual interference. This conclusion was evaluated in three experiments. Experiment 1 showed that, contrary to the predictions of an early-visual interference account, (a) diluters that are similar in terms of visual complexity induced different amounts of dilution and (b) the size of the dilution effect is proportional to the size of the Stroop interference effect when the diluters are used as single distractors. Experiments 2 and 3 revealed that when the position of the color bar is pre-cued, Stroop dilution disappears. We argue that these findings support Van der Heijden's (1992) attention-capture account of Stroop dilution.     

Elementary Classes in Basic Modal Logic

Dealing with topics of definability, this paper provides some interesting insights into the expressive power of basic modal logic. After some preliminary work it presents an abstract algebraic characterization of the elementary classes of basic modal logic, that is, of the classes of models that are definable by means of (sets of) basic modal formulas. Taking that for a start, the paper further contains characterization results for modal universal classes and modal positive classes.     

Causation in terms of production

Philosophical Studies - In this paper, we analyse actual causation in terms of production. The latter concept is made precise by a strengthened Ramsey Test semantics of conditionals: $$A \gg C$$...     

Examining psychokinesis: the interaction of human intention with random number generators--a meta-analysis

Séance-room and other large-scale psychokinetic phenomena have fascinated humankind for decades. Experimental research has reduced these phenomena to attempts to influence (a) the fall of dice and, later, (b) the output of random number generators (RNGs). The meta-analysis combined 380 studies that assessed whether RNG output correlated with human intention and found a significant but very small overall effect size. The study effect sizes were strongly and inversely related to sample size and were extremely heterogeneous. A Monte Carlo simulation revealed that the small effect size, the relation between sample size and effect size, and the extreme effect size heterogeneity found could in principle be a result of publication bias.     

A semiautomatic method for adding behavioral data to videotape records in combination with the Noldus Observer system

The Observer 3.0 (Noldus, 1991) was used as the base for a time-saving fine analysis of animal behavior. A PC controlled a shuttlebox and a shuttlebox control unit. Learning behavior was recorded on videotapes by an S-VHS camcorder with vertical interval time code (VITC), which was used to generate an observational data file (ODF). The observational system was enhanced by automatically recorded status signals from the PC as event markers on the soundtrack of the videotape. These signals were used to subdivide a training session into numbered trials during generation of the ODF. They were later used for a PC-aided fine analysis of behavioral events, such as attention responses (AR) and orienting responses (OR) during shuttlebox learning. In this way, a large number of both automatically inserted PC event markers and manually inserted, key-defined behavioral events were registered and analyzed effectively in a semiautomatic fashion. The system is illustrated with an analysis of shuttlebox avoidance data from gerbils (Meriones unguiculatus).     

Modeling Mental Spatial Reasoning About Cardinal Directions

This article presents research into human mental spatial reasoning with orientation knowledge. In particular, we look at reasoning problems about cardinal directions that possess multiple valid solutions (i.e., are spatially underdetermined), at human preferences for some of these solutions, and at representational and procedural factors that lead to such preferences. The article presents, first, a discussion of existing, related conceptual and computational approaches; second, results of empirical research into the solution preferences that human reasoners actually have; and, third, a novel computational model that relies on a parsimonious and flexible spatio‐analogical knowledge representation structure to robustly reproduce the behavior observed with human reasoners.     

Johann Christian August Heinroth (1773–1843): the first professor of psychiatry as a psychotherapist

Heinroth is known as the first professor of psychiatry. His chair was established 200 years ago on the 21st of October 1811. His major importance for the history of psychotherapy has not yet been acknowledged. Heinroth regarded restriction as well as activation as fundamental remedies for mental illnesses. Restriction meant making a voluntary decision to live a life based on religious faith and to abstain from earthly satisfaction. Within his specific psychotherapeutical module—the ‘‘direct-psychic’’method—he utilized the patient’s mental powers—mood, mind and will, but also his spirituality. His therapeutic approach additionally contained elements of cognitive,behavioral and conversational therapy.     

Can clouds dance? Part 2: An ERP investigation of passive conceptual expansion

Conceptual expansion, one of the core operations in creative cognition, was investigated in the present ERP study. An experimental paradigm using novel metaphoric, nonsensical and literal phrases was employed where individual differences in conceptual knowledge organization were accounted for by using participants’ responses to categorize the stimuli to each condition. The categorization was determined by their judgment of the stimuli on the two defining criteria of creativity: unusualness and appropriateness. Phrases judged as unusual and appropriate were of special interest as they are novel and unfamiliar phrases thought to passively induce conceptual expansion. The results showed a graded N400 modulation for phrases judged to be unusual and inappropriate (nonsense) or unusual and appropriate (conceptual expansion, novel metaphorical) relative to usual and appropriate (literal) phrases. The N400 is interpreted as indexing greater effort to retrieve semantic information and integrate the novel concepts presented through the phrases. Analyses of the later time-window showed an ongoing negativity that was graded in the same manner as the N400. The findings attest to the usefulness of investigating creative cognition using event-related electrophysiology.