Amir Muzur

The prefrontal cortex in sleep

Experimental data indicate a role for the prefrontal cortex in mediating normal sleep physiology, dreaming and sleep-deprivation phenomena. During nonrandom-eye-movement (NREM) sleep, frontal cortical activity is characterized by the highest voltage and the slowest brain waves compared to other cortical regions. The differences between the self-awareness experienced in waking and its diminution in dreaming can be explained by deactivation of the dorsolateral prefrontal cortex during REM sleep. Here, we propose that this deactivation results from a direct inhibition of the dorsolateral prefrontal cortical neurons by acetylcholine, the release of which is enhanced during REM sleep. Sleep deprivation influences frontal executive functions in particular, which further emphasizes the sensitivity of the prefrontal cortex to sleep.

Effects of lesions to area V6A in monkeys

In order to assess the role played by area V6A in visuomotor control, two adult green monkeys (Cercopithecus aethiops) were subjected to small, bilateral lesions in the anterior bank of the parieto-occipital sulcus. Before and after the lesions, monkeys were tested for naturally designed reaching, grasping and picking-up pieces of food from various positions on a plate and from a differently oriented narrow slit. All movements were recorded with closed circuit TV and analysed offline on a single-photogram basis for defective reaching and wrist orientation. V6A lesions provoked parietal weakness, reluctance to move, and specific deficits in reaching, wrist orientation and grasping. Recovery from the observed deficits was rapid, even after a second, contralateral lesion was given, creating a bilateral lesion. Thus, together with previous anatomical and electrophysiological data, these results directly support the hypothesis that area V6A is part of the network involved in the control of reaching movements and wrist orientation.

Cognitive performance by humans during a smoked cocaine binge-abstinence cycle.

Five cocaine-dependent individuals completed a 22-day inpatient study of sleep and cognition. Following 3 days of drug-free baseline, participants underwent 3 days of twice-daily smoked cocaine base self-administration (6 50-mg doses, 14 minutes apart), followed by 15 days of abstinence. Each morning and afternoon, the CDR repeatable, multiple-version, computerized cognitive battery (whose stability following practice has been documented) was administered. During abstinence, performance deteriorated on vigilance tasks (especially reaction time) as well as on immediate and delayed verbal recognition tasks but not on working memory tasks. Declines were most evident in the afternoon. Data suggest that abstinence can unmask cognitive deficits induced by chronic cocaine use and circadian factors may mediate their severity.

Effects of Praying and a Working Memory Task in Participants Trained in Meditation and Controls on the Occurrence of Spontaneous Thoughts

So-called “intrusive thoughts” appear independently from external stimuli and are the cause of severe disturbances in depressed patients. Following Bad-deleys 1986 discoveries regarding “articulatory suppression,” we investigated the influence of praying and of a working memory task on the number of spontaneous thoughts reported by 20 subjects compared to the control (quiet) state. Two groups of subjects were tested: those trained in meditation and controls. Significant reduction in simultaneous thought arousal was obtained during both the working memory task and the recitation of prayer. In all three experimental conditions, meditation practitioners reported significantly fewer spontaneous thoughts.

The nose between ethics and aesthetics : Sushruta's legacy

Objectives The aim of this article is to determine the origin of interest in rhinoplasty in ancient India, as well as to discuss the ethical and aesthetic implications of the nose in human history. Study Design Literature review. Materials and Methods Articles on history of medical ethics and rhinoplastic surgery were reviewed. Results Sushruta is considered “the father of plastic surgery,” and ancient India a cradle of rhinoplastic method called “the Indian method.” Origin of interest in and need for rhinoplasty is deeply rooted in ancient Indian society due to the practice of nose mutilations as a form of public punishment for immoral conduct. Conclusion The nose, once symbol of morality expressed through physical integrity, today becomes an important factor of human beauty. Rhinoplastic surgery is, both then and now, deeply pervaded with both ethics and aesthetics.

Visuomotor deficits and fast recovery after area V6A lesion in monkeys.

In order to study the involvement of area V6A in visually guided behavior, restricted lesions to the anterior bank of the parieto-occipital sulcus (POs) were made in two adult Cercopithecus aethiops monkeys, trained in visuomotor tests. Beside the known clinical signs of parietal deficit (abnormal posture of the arm contralateral to the most recent lesion and reluctance to use it), misreaching was evident soon after surgery and disappeared quickly. Uncertainties in a landmark test and prolonged response times to the pressing of light-buttons lasted for a few weeks and 1 month, respectively. As suggested by previous anatomical and physiological data, these findings confirm the role of the POs region in the execution of reaching movements. Moreover, they also demonstrate that following lesion, locally networked areas can rapidly adjust in order to re-establish pre-lesional behavior. These adjustments take place well before that any anatomical changes may occur.

Saints-protectors from snake bite: A short overview and a tentative analysis

A short overview of several saints, including Peter, Paul, John, George, Hilarius, Hubert, and Gaudentius, venerated in Christian tradition as protectors from snake bite, is offered as an introduction to a more substantial debate on the factors determining the choice of protectors in folk medicine, as well as on the possible adjuvant effect of (auto)suggestive therapy obtained by the invocation of saints.

The Cult of St. Lucia, Patroness of the Eyes: Some Examples from Croatian Ethnomedical Tradition

In the introductory part, the authors present several patrons/patronesses of the eyesand sight, as well as the protectors from eye diseases. In addition, presented is a shorthagiography of St. Lucia, the most famous among the patrons of the eyes. The secondpart is dedicated to the cult of St. Lucia, which has existed among the Croats from the10th century until present day. Testimonies to this are numerous churches, chapels,altars, paintings, sculptures, processions, pilgrimage, prayers, votive gifts, and manyother forms of folk piety. By reviewing several characteristic examples from Istriaand the region of Kvarner, the importance of this veneration is indicated, for generaland religious tradition as well as for the history of medicine, especially the history ofethno-ophthalmology.

Fritz Jahr: The Invention of Bioethics and Beyond

Since the discovery of his work in 1997, Fritz Jahr (1895-1953) has slowly become recognized as the author of the term and concept of bioethics. Jahrs ideas on bioethics were partly different from those shaped by Van Rensselaer Potter in the 1970s and, therefore, might be helpful for the further reform and broadening of modern bioethics. In this article, the authors elucidate ideas from lesser-known works by Jahr, especially those considering animal protection and teaching.

Birth of St. Mary (St. Anne's parturition) in the light of messages from medical education: three examples from Croatian sacral heritage.

Abstract Christian tradition treats birth in several characteristic motives. The most frequent is the Birth of Jesus Christ, while much rarer is the apocryphal motive of the birth of St. Mary. By analyzing three paintings from Croatian 16–17th-century sacral-art heritage, depicting the parturition of St. Anne (St. Marys Mother), the authors of this paper are trying to define the role of ethnomedical notions in the formation of modern medical and general culture.