On the Meaning of Hilbert's Consistency Problem (Paris, 1900)

The theory that ``consistency implies existence' was put forward by Hilbert on various occasions around the start of the last century, and it was strongly and explicitly emphasized in his correspondence with Frege. Since (Gödel's) completeness theorem, abstractly speaking, forms the basis of this theory, it has become common practice to assume that Hilbert took for granted the semantic completeness of second order logic. In this paper I maintain that this widely held view is untrue to the facts, and that the clue to explain what Hilbert meant by linking together consistency and existence is to be found in the role played by the completeness axiom within both geometrical and arithmetical axiom systems.     

Self-motion perception and vestibulo-ocular reflex during whole body yaw rotation in standing subjects: the role of head position and neck proprioception

Self-motion perception and vestibulo-ocular reflex (VOR) were studied during whole body yaw rotation in the dark at different static head positions. Rotations consisted of four cycles of symmetric sinusoidal and asymmetric oscillations. Self-motion perception was evaluated by measuring the ability of subjects to manually track a static remembered target. VOR was recorded separately and the slow phase eye position (SPEP) was computed. Three different head static yaw deviations (active and passive) relative to the trunk (0°, 45° to right and 45° to left) were examined. Active head deviations had a significant effect during asymmetric oscillation: the movement perception was enhanced when the head was kept turned toward the side of body rotation and decreased in the opposite direction. Conversely, passive head deviations had no effect on movement perception. Further, vibration (100 Hz) of the neck muscles splenius capitis and sternocleidomastoideus remarkably influenced perceived rotation during asymmetric oscillation. On the other hand, SPEP of VOR was modulated by active head deviation, but was not influenced by neck muscle vibration. Through its effects on motion perception and reflex gain, head position improved gaze stability and enhanced self-motion perception in the direction of the head deviation.     

‘Kimberley Brownlee: Being Sure of each Other. An Essay on Social Rights and Freedoms’ Oxford: Oxford University Press, 2020

Ethical Theory and Moral Practice -     

Variability in the “stereotyped” prey capture sequence of male cuttlefish (<Emphasis Type="Italic">Sepia officinalis</Emphasis>) could relate to personality differences

Studies of animal personality have shown consistent between-individual variation in behaviour in many social and non-social contexts, but hunting behaviour has been overlooked. Prey capture sequences, especially in invertebrates, are supposed to be quite invariant. In cuttlefish, the attack includes three components: attention, positioning, and seizure. The previous studies indicated some variability in these components and we quantified it under the hypothesis that it could relate to personality differences. We, therefore, analysed predation sequences of adult cuttlefish to test their association with personality traits in different contexts. Nineteen subjects were first exposed to an “alert” and a “threat” test and then given a live prey, for 10 days. Predation sequences were scored for components of the attack, locomotor and postural elements, body patterns, and number of successful tentacle ejections (i.e. seizure). PCA analysis of predatory patterns identified three dimensions accounting for 53.1%, 15.9%, and 9.6% of the variance and discriminating individuals based on “speed in catching prey”, “duration of attack behaviour”, and “attention to prey”. Predation rate, success rate, and hunting time were significantly correlated with the first, second, and third PCA factors, respectively. Significant correlations between capture patterns and responsiveness in the alert and threat tests were found, highlighting a consistency of prey capture patterns with measures of personality in other contexts. Personality may permeate even those behaviour patterns that appear relatively invariant.     

Do Coping Strategies Discriminate Eating Disordered Individuals Better Than Eating Disorder Features? An Explorative Study on Female Inpatients with Anorexia and Bulimia Nervosa

The purpose of this explorative research was to examine how the COPE (Coping Orientation to Problem Experienced Inventory), an established instrument for measuring coping styles, and EDI-2 (Eating Disorder Inventory-2), a widely used questionnaire for assessing psychological and behavioural features of eating disorders (ED), discriminate among healthy individuals, inpatients with anorexia nervosa (AN) and inpatients with bulimia nervosa (BN). A discriminant analysis approach was used. Results showed that coping styles such as positive attitude, planning and social support are even more discriminative variables than eating disorder features. Implications for further studies are discussed.     

Media exposure to terrorism and people's risk perception: The role of environmental sensitivity and psychophysiological response to stress

Terrorist attacks have a destabilizing impact on the general population, causing distress and fear. However, not all individuals are equally susceptible to the effects of terror threat. This study aimed to examine whether exposure to terrorism-related pictures interacted with individual differences in environmental sensitivity and psychophysiological response to stress to explain people's risk perception, operationalized as perceived likelihood of a terrorist attack and willingness to trade off one's privacy to increase national security. Ninety-five university students were randomly assigned to one of two conditions (terrorism-related vs. neutral pictures). After watching the pictures, they answered questions concerning risk perception and completed questionnaires. Stress was induced by the Mannheim Multicomponent Stress Test, during which heart rate was recorded. Results showed that the perceived likelihood of future attacks was affected by the interaction between exposure to terrorism pictures and psychophysiological reactivity to stress, whereas willingness to trade off one's privacy to improve national security was influenced by the interaction between exposure to terrorism pictures and environmental sensitivity. The study suggests that individuals high in sensitivity and psychophysiological stress reactivity are particularly affected by terrorism-related pictures. Psychologists should direct their efforts to raise general awareness of the negative effects, especially for some people, of such media coverage.     

Neuropsychological tools to predict conversion from amnestic mild cognitive impairment to dementia. The TREDEM Registry

Most of the studies about conversion from Mild cognitive impairment (MCI) to dementia have focused on amnestic MCI (aMCI) which is considered a preclinical phase of Alzheimer’s disease. The aim of the present study was to identify neuropsychological tools that would best predict conversion from aMCI to dementia. Fifty-five aMCI subjects on the Treviso Dementia Registry were investigated. They underwent a neuropsychological evaluation during their first assessment and again at follow-up. Cox proportional-hazard regression models were created to measure the association between the dependent variable (dementia diagnosis or MCI status maintenance) and the neuropsychological test scores at baseline. The sample (28 women and 27 men; mean age 76.82 ± 5.88 years; education 7.62 ± 3.99 years) was observed for an average time of 2.17 ± 1.25 years. A Cox backward stepwise regression showed that the Rey Auditory Verbal Learning Test, Delayed Recall (p = .041) and Semantic Verbal Fluency tests (p = .031) appear to be useful in predicting conversion to dementia.