Propositional attitudes and formal ontology

This paper develops — within an axiomatic theory of properties, relations, and propositions which accords them well-defined existence and identity conditions — a sententialist-functionalist account of belief as a symbolically mediated relation to a special kind of propositional entity, theproxy-encoding abstract proposition. It is then shown how, in terms of this account, the truth conditions of English belief reports may be captured in a formally precise and empirically adequate way that accords genuinely semantic status to familiar opacity data.I am deeply indebted to Edward Zalta for many helpful comments and suggestions.     

Early selective-attention effect on evoked potential reinterpreted

In a dichotic listening situation stimuli were presented one at a time and at random to either ear of the subject at constant inter-stimulus intervals of 800 msec. The subject's task was to detect and count occasional slightly different stimuli in one ear. In Experiment 1, these ‘signal’ stimuli were slightly louder, and in Experiment 2 they had a slightly higher pitch, than the much more frequent, ‘standard’, stimuli. In both experiments signals occured randomly at either ear. Separate evoked potentials from three different locations were recorded for each of the four kinds of stimuli (attended signals, unattended signals, attended standards, unattended standards). Contrary to Hillyard et al. (1973), no early (N₁ component) evoked-potential enhancement was observed to stimuli to the attended ear as compared with those to the unattended ear, but there was a later negative shift superimposed on potentials elicited by the former stimuli. This negative shift was considered identical to the N₁ enhancement of Hillyard and his colleagues which in the present study was forced, by the longer inter-stimulus interval used, to demonstrate temporal dissociation with the N₁ component. The ‘Hillyard effect’ was, consequently, explained as being caused by a superimposition of a CNV kind of negative shift on the evoked potential to the attended stimuli rather than by a growth of the ‘real’ N₁ component of the evoked potential.     

On the detection of a brief signal in the temporal center of a noise masker of varying duration

The threshold of a brief signal temporally centered in a noise masker first increases and then decreases as the masker is increased in duration. We discuss two explanations for this “over-shoot” phenomenon which consider the role of peaks of an exponentially weighted sliding integrator. One such explanation takes into account the finding that the steepness of the psychometric function continues to increase monotonically as its location moves first right and then left.     

Choice reaction time with a random foreperiod

Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.     

Smoking cessation with behaviour therapy or acupuncture—A controlled study

Five hundred and fifty-eight cigarette smokers (mean 31 cigarettes/day) were randomized in four groups: Acupuncture, Behaviour Therapy, Placebo Medication and Waiting-list Control. The life-table analysis of smoking cessation showed, at a 12-month follow-up, no difference between Acupuncture, Behaviour Therapy and Placebo. Differences appeared only in an analysis of the abstinent subjects at each data point. Behaviour Therapy and Acupuncture accounted for significantly more abstinent subjects than Placebo at the end of the 2-week therapeutic phase. However at 9 and 12 months Acupuncture had a statistically-significant greater number of abstinent subjects than Behaviour Therapy, but there was no difference between Acupuncture and Placebo. The percentage decrease in smoking from baseline appeared significantly greater at 12 months in the first three groups than in the Control conditions. However, as in most smoking-cessation studies, the overall effect was small and non-specific. The results reflect the importance of maintenance programmes and of the prevention of addiction.     

Motivation as a function of success frequency

Motivation and Emotion - It is well-established that intermediate challenge is optimally motivating. We tested whether this can be quantified into an inverted-U relationship between motivation and...     

Philosophy of medicine in 2021

Theoretical Medicine and Bioethics -