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We report a variant of mirror hand in a 3.5-year-old boy who presented with multiple fingers. The x-ray revealed an attempt at fusion of 2 hypoplastic radii, 1 ulna, and multiple fingers. The unique feature of this case is a broad radius with proximal notching suggesting failed incomplete duplication. The reasons for this duplication and duplication of the fingers appear to be different.
The principles and process of a model of clinical supervision for psychotherapy are presented and described through two cases. The model draws heavily from Bowen's family systems theory and Peplau's theory of interpersonal relations. The relationships in the client-family, client-therapist, and therapist-supervisor systems mirror each other, and changes in self-definition, and in the management of anxiety of persons in one system catalyzes changes in parallel systems. Two cases illustrate the model. In the first case, anxiety needed to be raised to levels optimal for learning. In the second case, no learning occurred until levels of anxiety were reduced.
When primates passively observe other subjects perform specific gestures or actions, premotor and motor cortical areas involved in the internal representation and actual execution of those actions exhibit neuronal activation. This mirror mechanism matches observation, representation, and execution, facilitating internal motor rehearsal, imitation, recognition of actions by others and their meanings, and social learning. Schizophrenic patients have deficits in processing affect displayed by other people's faces, which likely relates to the poor social adaptation and functioning seen in the condition. We hypothesized that, when correctly performing working-memory tasks requiring facial affect processing, schizophrenic patients would show relative increased activity in brain areas involved in social learning and in the internal representation of facial expressions when compared to controls. We used functional magnetic resonance imaging in schizophrenic patients and normal controls to detect relative changes of blood flow in cortical areas related to the representation of facial expressions while the subjects performed simple working-memory tasks with facial emotion diagrams or color circles as cues. We found that, when the task cues were facial expressions in contrast to color circles, the schizophrenic group exhibited increased activation of the face movement areas in motor and pre-motor cortex.
The article contributes to the quest to relate global data on brain and behavior (e.g. from PET, Positron Emission Tomography, and fMRI. functional Magnetic Resonance Imaging) to the underpinning neural networks. Models tied to human brain imaging data often focus on a few "boxes" based on brain regions associated with exceptionally high blood flow, rather than analyzing the cooperative computation of multiple brain regions. For analysis directly at the level of such data, a schema-based model may be most appropriate. To further address neurophysiological data, the Synthetic PET imaging method uses computational models of biological neural circuitry based on animal data to predict and analyze the results of human PET studies. This technique makes use of the hypothesis that rCBF (regional cerebral blood flow) is correlated with the integrated synaptic activity in a localized brain region. We also describe the possible extension of the Synthetic PET method to fMRI. The second half of the paper then exemplifies this general research program with two case studies, one on visuo-motor processing for control of grasping (Section 3 in which the focus is on Synthetic PET) and the imitation of motor skills (Sections 4 and 5, with a focus on Synthetic fMRI). Our discussion of imitation pays particular attention to data on the mirror system in monkey (neural circuitry which allows the brain to recognize actions as well as execute them). Finally, Section 6 outlines the immense challenges in integrating models of different portions of the nervous system which address detailed neurophysiological data from studies of primates and other species; summarizes key issues for developing the methodology of Synthetic Brain Imaging; and shows how comparative neuroscience and evolutionary arguments will allow us to extend Synthetic Brain Imaging even to language and other cognitive functions for which few or no animal data are available.
To evaluate the reactivity to psychological stress in patients with essential hypertension we investigated hemodynamic and endocrinologic changes during a mental arithmetic task (MAT) and a mirror drawing test (MDT) in 10 hypertensive subjects. Hemodynamic changes were assessed continuously using an ambulatory radionuclide cardiac detector. There were significant increases in systolic blood pressure (deltaSBP: +37.8 +/- 11.1 and +41.0 +/- 9.4 mm Hg during MAT and MDT, respectively, P < .01) and diastolic blood pressure (deltaDBP: +17.5 +/- 3.1 and +21.2 +/- 3.9 mm Hg, P < .01) and in heart rate (deltaHR: +17.1 +/- 5.3 and +12.5 +/- 2.9 beats/min, P < .01) during both tasks in association with an increase in cardiac output (CO). The plasma levels of norepinephrine and epinephrine increased during both the MAT (deltaNE: +0.074 +/- 0.022 ng/mL, P < .01; deltaEP: +0.068 +/- 0.025 ng/mL, P < .01) and the MDT (deltaNE: +0.067 +/- 0.034 ng/mL, P < .01; deltaEP: +0.030 +/- 0.011 ng/mL, .05 < P < .1). Although the deltaNE was similar in response to the MAT and MDT, the deltaEP during the MDT tended to be less than half the deltaEP during the MAT (.05 < P < .10). The deltaEP was positively correlated with the deltaDBP and the deltaCO during both tasks and with the deltaSBP and the deltaHR during the MAT. These findings suggest that MAT- and MDT-induced increases in BP were attributable mainly to an increase in CO, possibly as the result of stimulation of the sympathoadrenomedullary system. However, the sympathoadrenomedullary system appeared to be more closely associated with the hemodynamic responses during the MAT than during the MDT.
We have combined functional maps of retinotopy (eccentricity and meridian mapping), object category, and motion in a group of subjects to explore the large-scale topography of higher-order object areas. Our results reveal seven consistent category-related entities situated in the occipito-temporal cortex adjoining early visual areas. These include two face-related regions, three object-related regions, and two building-related regions. Interestingly, this complex category-related pattern is organized in a large-scale dorso-ventral mirror symmetry of object category. Furthermore, correlating this pattern to the map of visual field eccentricity, we found that the entire network of areas could be related to a single and unified eccentricity map. We hypothesize that this large-scale organization points to a possible development of high-order object areas through extension and specialization of a single proto-representation.
Understanding the functional organization of the human primary auditory cortex (PAC) is an essential step in elucidating the neural mechanisms underlying the perception of sound, including speech and music. Based on invasive research in animals, it is believed that neurons in human PAC that respond selectively with respect to the spectral content of a sound form one or more maps in which neighboring patches on the cortical surface respond to similar frequencies (tonotopic maps). The number and the cortical layout of such tonotopic maps in the human brain, however, remain unknown. Here we use silent, event-related functional magnetic resonance imaging at 7 Tesla and a cortex-based analysis of functional data to delineate with high spatial resolution the detailed topography of two tonotopic maps in two adjacent subdivisions of PAC. These maps share a low-frequency border, are mirror symmetric, and clearly resemble those of presumably homologous fields in the macaque monkey.
Practice makes perfect, but the role of repetitions in skill learning is not yet fully understood. For example, given a similar number of trials on a given task, it is debated whether repeating and non-repeating items are learned by the same neural process. When one is given training with both types of items--does one learn two separate skills, or only one? Here we show, using a mirror reading task, that practice trials with trial-unique words, and practice trials with repeated words, count towards learning to a different degree. There was no interaction between the time-course of learning repeated and unique words even within the same individuals given mixed training. While repeated words were learned faster than unique words, the repetitions-dependent gains diminished with training beyond a small number of repetitions. Moreover, the gains in performance could not be accounted for solely by the number of repetitions, as assumed by power-law models of learning; rather, the passage of time was a critical factor. Finally, our results suggest that although both repeated and new words were learned by both declarative and procedural memory mechanisms, even a single repetition of specific words could lead to the establishment of a selective differential representation in memory. The results are compatible with the notion of a repetition-sensitive process, triggered by specific repeating events. This 'repetition counter' may be a critical trigger for the effective formation of procedural as well as some type of declarative memory.
The physics of ultrasound and mechanisms of artifacts are well-known. In this report, an unusual manifestation of mirror-image artifact (MIA) that is completely different from the real image of the structure, demonstrated during a routine abdominal ultrasonographic examination, is described. There have hitherto been no reports on the ultrasonographic appearance of such a MIA.
Three variants of the liposome fusion (coalescence) method to produce supported lipid bilayers, containing the ganglioside GM1 on silicon nitride surfaces, were studied. The first procedure involved attachment and fusion of liposomes containing DMPC, GM1 and a small amount of biotinylated lipid (Biotin-LC-DPPE) to a streptavidin coated surface. Direct fusion of liposomes composed of a mixture of DPPC, DPPG, DPPE, GM1 and cholesterol to the surface were the second variant. The final method utilised the second type of liposomes, fused onto a streptavidin layer with a small amount of exposed hydrophobic tails. The methods produced similar lipid layers, but with different ways of attachment to the surface. The binding of cholera toxin B-subunit (CTB) towards these sensor surfaces was measured in a resonant mirror biosensor instrument and the activity and longer-term stability of the layers were examined. The prepared surfaces were also imaged by atomic force microscopy (AFM) in liquid to characterise the topography of the lipid layers. The binding efficiency of CTB towards these surfaces was discussed in terms of lipid fluidity and surface roughness.
The interaction of monoclonal anti-atrazine antibody D6F3 with free and immobilized atrazine was studied using the resonant mirror-based optical biosensor system IAsys. The binding of antibody to atrazine immobilized on silanized surface through albumin spacer was studied in the presence of methanol. The highest affinity was observed in 10% methanol, the kinetic equilibrium association constant KA was 1.16 x 10(9) mol-1 l compared to 4.3 x 10(8) mol-1 l determined in water. The surface binding capacity was 2-fold lower in the presence of methanol compared to aqueous buffer solution. The kinetic rate constants were significantly improved with low contents of methanol; the fastest association and slowest dissociation occurred at 5 and 10% methanol, respectively. The formation of immunocomplexes was observed even in the presence of 50% methanol. To avoid possible disturbing effects resulting from the immobilization of atrazine, the interaction of free atrazine and antibody was studied using the competitive procedure. The determined values of KA were 9.35, 0.73 and 410 x 10(6) mol-1 l for interactions carried out in 10, 30 and 50% methanol, respectively. For practical determination of atrazine using this antibody, the content of 10% methanol in the assay mixture seems to be the best choice. Thirty percent methanol resulted in the lowest affinity; 50% methanol provides the highest affinity, but much smaller signal is measured. The affinity biosensor system IAsys appeared to be a suitable, rapid and convenient tool for studies of binding interactions in the presence of organic solvents.
About half of the readers of this article would not be able to tell whether a picture of the Mona Lisa is correct or mirror-reversed. Neuropsychological studies may help explain this striking dissociation between the ability to identify images and memory for their handedness.
A 31 year-old woman with familial congenital mirror movements not associated with other neurological defects underwent a detailed neurophysiological evaluation including: voluntary electromyographic activity recorded from upper limbs in response to acoustic stimuli, motor evoked potentials from the thenar muscles to focal transcranial magnetic stimulation, F waves from upper extremities, scalp somatosensory evoked potentials and long-latency responses from thenar muscles to electric stimulation of the median nerve. The results were consistent with the presence of fast-conducting pathways connecting each hand motor cortex with both contra- and ipsilateral spinal motoneurones.
Despite good evidence to the contrary, the Spanish singing teacher Manuel Garcia is still credited by many to have been the discoverer of the mirror for inspecting the larynx. Although the adoption of this technique into clinical practice, and thus the beginning of laryngology as a specific discipline, is rightly credited to others Manuel Garcia achieved unwarranted fame ... if not fortune. Careful examination of the published literature has substantiated the claim that 26 years prior to the paper presented on Garcia's behalf to the Royal Society of London, Babington had described to the Hunterian Society a similar device which later evidence indicated had been used clinically on at least one laryngologist. This claim was also supported by no less than Morell Mackenzie in a published lecture in 1864, nine years after Garcia's lecture. Possible explanations for this aberration of justice are considered.
OBJECTIVE: To report the residency training experience of two neurologists, focusing on setting and diagnoses encountered. METHODS: Data from prospective patient logs kept by the authors during residencies completed a decade apart were compared with each other and the literature. RESULTS: The range of diagnoses was broadly similar between residencies, as were the proportions of common or uncommon disorders, and the proportion of cases without a neurological diagnosis. Although most patients were seen in in-patient settings, the rates at which common neurological conditions and functional disorders were seen was comparable to published experiences of community neurologists. CONCLUSIONS: The diagnostic profile of North American neurology residency appears to be relatively stable, regardless of location or date of training. In several respects, the content of current neurology residencies mirrors clinical practice well. Changes to residency training are doubtless needed, but they should be guided by a clear understanding of the experiences of contemporary trainees.
We report two autopsy proven cases of unguarded mitral orifice associated with mirror-imaged atrial arrangement, discordant atrioventricular connections, double outlet right ventricle, pulmonary valvar stenosis or atresia, and atrialisation of the morphologically left ventricle. The morphologically left atrioventricular junction was devoid of valvar leaflets, and there was no tension apparatus within the ventricle. To the best of our knowledge, this is the first description of this rare cardiac malformation.
To date, almost all patients reported with hypoplasia of the left heart have had usual atrial arrangement, with a small proportion known to have left or right isomerism. As far as I am aware, however, only one patient has previously been described with mirror-imaged arrangement of the heart and organs. In this report, I describe the second case.
We describe a 6-year-old boy with a right-sided heart part of the Kartagener syndrome, complicated by presence of a perimembranous ventricular septal defect. The defect was closed interventionally using the Amplatzer asymmetrical occluder for ventricular septal defects. The procedure was event-free. Non-operative closure of a ventricular septal defect in this patient demonstrated no other difficulty than mirror-imaged thinking, thus giving evidence that such treatment also can be offered to patients with positional anomalies.