Nosologic evaluation of oculopharyngeal myopathic syndromes

Three patients with oculopharyngeal involvement of neuromuscular origin are presented: one patient suffering from an oculopharyngeal neuromuscular disease (developing an oculopharyngeal muscular dystrophy?) and two patients representing a neuromuscular mitochondriopathy. There is no evidence that the oculopharyngeal myopathy and neuromuscular disease, respectively, are the same, despite the simularity of the syndrome. The different clinico-pathological types of oculopharyngeal syndromes are discussed. Following-up the development of further manifestations of the oculopharyngeal syndrome can helf classifying them.     

Analysis of probabilistic classification learning in patients with Parkinson's disease before and after pallidotomy surgery

This study examined the characteristics of probabilistic classification learning, a form of implicit learning previously shown to be impaired in patients with basal ganglia dysfunction (e.g., Parkinson's disease). In this task, subjects learn to predict the weather using associations that are formed gradually across many trials, because of the probabilistic nature of the cue-outcome relationships. Patients with Parkinson's disease, both before and after pallidotomy, and age-matched control subjects, exhibited evidence of probabilistic classification learning across 100 training trials. However, pallidotomy appears to hinder the learning of associations most implicit in nature (i.e., weakly associated cues). Although subjects were most sensitive to single-cue associations when learning the task, there is evidence that cue combinations contribute significantly to probability learning. The utility of multiple dependent measures is discussed.     

Methodologies of affective classification

Three methodologies to classify the affective domain are reviewed: phenetic, cladistic, and ontological. The merits and seeming deficiencies of these approaches are analyzed, and illustrative applications of these methodologies are presented. A systems analysis of the affective domain is proposed as most adequately performing the classification functions of grouping elements to emphasize their autonomy and homonomy, indicate their nature and degree of relatedness, and structurally represent abstract conceptualizations of this domain.     

Locke's theory of classification

In §155 of his New Theory of Vision Berkeley explains that a hypothetical ‘unbodied spirit’ ‘cannot comprehend the manner wherein geometers describe a right line or circle’.1 ¹All references to Berkeley are from, A. A. Luce and T. E. Jessop (eds.), The Works of George Berkeley, Bishop of Cloyne (London: Thomas Nelson and Sons, Ltd., 1948) The following abbreviations are used: An Essay Towards A New Theory of Vision, section x = New Theory x; Philosophical Commentaries, entry x = Commentaries x; Part I of A Treatise concerning the Principles of Knowledge, section x = Principles x. All other references to Berkeley's works are of the form The Works of George Berkeley, Bishop of Cloyne, volume x, page y = Works, x, y. The reason for this, Berkeley continues, is that ‘the rule and compass with their use being things of which it is impossible he should have any notion.’ This reference to geometrical tools has led virtually all commentators to conclude that at least one reason why the unbodied spirit cannot have knowledge of plane geometry is because it cannot manipulate a ruler or a compass. In this article I will show that such an interpretation is flawed. I will instead argue that Berkeley's understanding of Euclidian geometry was based on Isaac Barrow's account of the foundations of geometry. On this view geometrical objects are conceived in terms of the idealized motion that generates the objects of geometry. Consequently, that what the unbodied spirit cannot do in this context is to form an idea of motion rather than being unable to handle geometrical tools.     

Functional classification of obsessive-compulsive phenomena

A classification of obsessive-compulsive phenomena based on the functional definition of obsessions as anxiety/discomfort producing and compulsions as anxiety/discomfort reducing is proposed. Based on the assumption of a functional equivalence between external and internal obsessive-compulsive behavior, four essential obsessive-compulsive forms are derived: (1) obssesions, (2) obsessions plus successful compulsions (anxiety/discomfort reducing), (3) obsessions plus obsessionalized compulsions (anxiety increasing), and (4) rituals consisting mainly of stereotyped, overt or covert behaviors (autonomous of anxiety/discomfort and/or obsessions). In addition, it is hypothesized that forms 1–4 represent developmental stages in the progress of obsessive-compulsive symptomatology, increasing in the order specified in complexity and severity and having varying prognostic implications. Finally, an attempt is made to suggest stage-specific behavioral treatment strategies.     

The classification of neuropsychological deficit

The study involves classification of neuropsychiatric patients on the basis of neuropsychological and intelligence test performance. One hundred twenty-five hospitalized male neuropsychiatric patients with various diagnoses were administered the Halstead-Reitan and Luria-Nebraska neuropsychological test batteries, as well as the Wechsler Adult Intelligence Scale. A cluster analysis was performed for each of those three procedures utilizing Ward's method. It was found in all cases that clusters were determined on the basis of level rather than pattern of performance. Relationships were found between cluster membership and age, education, and presence or absence of structural brain damage but were not found for diagnoses of schizophrenia or alcoholism. Schizophrenic and alcoholic patients were found in all clusters in the case of all three test procedures. Differences in clustering among the three test procedures were noted, with the WAIS being relatively more sensitive to educational differences while the Halstead-Reitan was more sensitive to age differences. The clinical utility of classifying patients on the basis of neuropsychological and cognitive test performance was discussed.Acknowledgement is made to the Veterans Administration for support of this research.     

The perceptual classification of speech

By employing new methods of analysis to the physical signal, a number of researchers have provided evidence which suggests that there may be invariant acoustic cues which serve to identify the presence of particular phonetic segments (e.g., Kewley-Port, 1980; Searle, Jacobson, & Rayment, 1979; Stevens & Blumstein, 1978. Whereas previous studies have focused upon the existence of invariant properties present in the physical stimulus, the present study examines the existence of any invariant information available in the psychological stimulus. For this purpose, subjects were asked to classify either a series of full-CV syllables ([bi], [bε], [bo], [??], [di], [d∈], [do], [??]) or one of two series of chirp stimuli consisting of information available in the first 30 meec of each syllable. The full-formant chirp stimuli consisted of the first 30 msec of each syllable, whereas the two-formant chirps were composed of the first 30 msec of only the second and third formants. The object of the present study was to determine whether or not there was sufficient information available in either the full- or two formant chirp series to allow subjects to group the stimuli into two classes corresponding to the identity of the initial consonant of the syllables (i.e., [b], or [d]). A series of classification tasks were used, ranging from a completely free sorting task to a perceptual learning task with experimenter-imposed classifications. The results suggest that there is information available in the full-formant chirps, but not in the two-formant chirps, which allows subjects to group the sounds into classes corresponding to the identity of the initial consonant sounds.     

On the classification of diseases

Identifying the necessary and sufficient conditions for individuating and classifying diseases is a matter of great importance in the fields of law, ethics, epidemiology, and of course, medicine. In this paper, I first propose a means of achieving this goal, ensuring that no two distinct disease-types could correctly be ascribed to the same disease-token. I then posit a metaphysical ontology of diseases—that is, I give an account of what a disease is. This is essential to providing the most effective means of interfering with disease processes. Following existing work in the philosophy of medicine and epidemiology (primarily Christopher Boorse; Caroline Whitbeck; Alexander Broadbent), philosophy of biology (Joseph LaPorte; D.L. Hull), conditional analyses of causation (J.L. Mackie; David Lewis), and recent literature on dispositional essentialism (Stephen Mumford and Rani Anjum; Alexander Bird), I endorse a dispositional conception of disease. Following discussion of various conceptions of disease-identity, their relations to the clinical and pathological effects of the diseases in question, and how diseases are treated, I conclude (i) that diseases should be individuated by their causes, and (ii) that diseases are causal processes best seen as simultaneously acting sequences of mutually manifesting dispositions.     

Knowledge-based classification of ill-defined categories

In this paper, I report an exploratory study which investigated the role that prior knowledge plays in influencing classification learning. Under neutral or knowledge-imposing instructions, subjects learned to classify exemplars into categories that either were or were not linearly separable. Linearly separable categories are those categories whose members can be correctly classified based on an additive summation of weighted attribute information. Following category learning, the subjects were given transfer tests. A major finding was that knowledge facilitated the learning of linearly separable categories but interfered with the learning of not linearly separable categories. Quantitative analyses revealed that the knowledge facilitated category learning of the linearly separable categories by influencing the storage and reliance on both prototypical and exemplar information.     

Causation and melanoma classification

In this article, I begin by giving a brief history of melanoma causation. I then discuss the current manner in which malignant melanoma is classified. In general, these systems of classification do not take account of the manner of tumour causation. Instead, they are based on phenomenological features of the tumour, such as size, spread, and morphology. I go on to suggest that misclassification of melanoma is a major problem in clinical practice. I therefore outline an alternative means of classifying these tumours based on causal factors. By analogy with similar systems that have recently emerged for other cancers, I suggest that this causal classification is likely to be both workable and helpful, even in the absence of a full causal-mechanistic understanding of the aetiology of the tumour.