Mathematical approach to integrating the "neuron-module" and the "cell-assembly"

The structural and functional unit of neuropsychic activity is approached in a mathematical way referring to some basic features of both the "neuron-module" and the "cell-assembly." The proposed units, called modules, have specific synchronous inputs and outputs, more abundant inner than outer connectivity, and their states are assumed representing concepts. Neurons in the model possess finite, discrete scales of states with inhomogeneous distances. Neighbouring relations are asymmetric (like the synapses) and of both intra- and inter-modular type. The actual states of neighbouring cells form a collective state. This is an emergent phenomenon, formally a complex, not necessarily explicit function of the cellular variables. Collective states belonging to the neurons in a module form the modular state. Thus, the influence of different cells on the modular state depends on their arborization, reflecting that the organization of the module holds greater significance than its size. Some of the modular states are assumed as "known", others are described by fuzzy sets representing definite and ambiguous concepts, respectively. A specified version of the model with application to visual pattern recognition is summarized for illustration.     

Treating the patient who "can't" versus treating the patient who "won't"

Patients who can't do what they need to do should be treated differently than those who won't take responsibility for themselves. Mistakenly treating one as the other leads to a confusing sense of failure or may foster regression, and the clinical disagreement between colleagues readily takes on a characteristic moral tone.     

Office evaluation of the "tired" or "sleepy" patient

In an outpatient neurologic practice, the patient complaint of being "tired" is frequently encountered yet often not specifically addressed. Clarifying the symptoms and determining whether the tiredness is the result of excessive daytime sleepiness versus fatigue or weakness is the first step in diagnosing and treating the patient. A detailed neurologic and sleep history and exam can often distinguish among these different symptoms, establish the potential causes of excessive sleepiness, and decide on the additional ancillary tests that may be helpful to determine the underlying etiology. Understanding the etiology of patient's symptoms is necessary to initiate appropriate treatment.     

"Object vision" and "spatial vision": the neuropsychological evidence for the distinction

The distinction between "object vision" and "spatial vision" was made by Ungerleider and Mishkin (1982) on the evidence of behavioural and neuroanatomical studies, largely with monkeys. It holds that separate cortical systems are involved, the occipito-temporal in object vision, the occipito-parietal in spatial vision. This distinction has been unquestioned; it appears as though fact in influential textbooks; but has never been subjected to critical scrutiny. Theoretically, there are substantial difficulties, for instance because during perception objects do not form a special category, apart from their features; and because shape, pattern and size are spatial features of objects. Empirically, for the monkey the behavioural distinction does not hold (because parietal cortex is not the sole cortical area involved in "spatial vision"); and in man because parietal lesions have long been known to lead to impaired perception of incomplete pictures. Moreover, although Ungerleider and Mishkin do not generalise their distinction to touch, this sense deserves consideration, given that Mishkin had earlier argued that vision and touch have a similar organisation. In touch there are direct anatomical connections between the areas serving "object touch" and "spatial touch", and both in man and in the monkey it seems established that the same region processes spatial performance in vision and in touch. Further work is needed particularly on the spatial disorder after parietal lesions: in the monkey, research has frequently been confined to one non-specific test; in man, important differences related to the laterality of the lesion, have only recently emerged. Then "spatial performance" may be found to be more closely linked to motor output than to sensory input.     

On the development of the "borderline-child-to-be"

A model of the development of the borderline child is presented. It is organized around three central themes: early experiences of being overwhelmed (trauma); the evolution of developmental deficits; and desperate reliance on ultimately maladaptive survival mechanisms for coping.     

Exploring the pain "neuromatrix"

A considerable number of functional imaging studies have demonstrated the involvement of multiple central regions during the experience of pain. These regions process information in circuits that can broadly be assumed to process the affective, sensory, cognitive, motor, inhibitory, and autonomic responses stimulated by a noxious event. The concept of a "neuromatrix" for pain processing is, therefore, well supported. There is, however, scant evidence for any particular regional or circuit dysfunction during clinical pain. To be clinically useful, functional imaging may have to step beyond the generalities of the neuromatrix.     

The "military family syndrome" revisited: "by the numbers"

Because concerns have been raised about high levels of psychopathology in military children, the authors used standardized psychopathology rating scales to survey 213 six-to twelve-year-old children of military parents and their parents. Results from children's symptom self-reports, as well as from teachers' ratings of children, indicated that children's symptom levels were at levels consistent with national norms. In contrast, parents' (especially mothers') ratings of children were significantly higher than national norms, as were parents' ratings of their own symptoms. Also, parents' own symptom reports showed somewhat stronger relationships with life stressors presumably affecting the child than did the children's and teachers' reports. Results suggest that parents' reports of children's symptoms may be mediated by the effects of military life stressors on the parents, but these stressors do not necessarily result in higher symptoms in the children. Overall results do not support the notion that levels of psychopathology are greatly increased in children of military parents. Further studies of military families should address the effects of rank and socioeconomic status, housing, and the current impact of life stressors on the parents as well as the children in order to avoid drawing erroneous conclusions about parts or all of the military community.     

"Organic" and "functional" diseases of the nervous system.

The aim of this paper is to discuss whether in the realm of diseases of the nervous system the concept of "dysfunctional" versus "organic" disorders is still useful. The knowledge on the Common Brain Stem System (CBSS) described by Hess is reviewed in order to underline its role as a control centre integrating all the homeostatic and adaptive nervous activities, and in this context, the nervous control of the cardiovascular system is examined, particularly in relation to higher nervous activities. The neurogenic syncopes are chosen as examples of the either "organic" or "dysfunctional" conditions whose semeiotic and pathophysiological distinctive features are analysed. In conclusion the distinction between "organic" diseases and "dysfunctional" disorders seems to be still justified, mainly for the nervous affections involving the homeostatic-adaptive properties of the CBSS.     

"Timers" and "scanners" among orientation detectors of the visual cortex in the cat

Acute experiments on immobilized cats were carried out to check the suggestion that a special class of neurons ("timers") which do not change time properties of responses with variations in light bar orientation exists in the visual cortex. Previously neurons of the visual cortex with a dynamic shift of preferable orientation ("scanners") were revealed. Among 76 neurons 27 (36%) showed different properties: stability of latencies in the orientation range, shorter initial and peak latencies, duration and time of the discharge frequency increase, wider orientational tuning and worse relations between magnitudes of responses to preferred and nonpreferred stimuli. They were considered as representatives of the suggested "timers".