Alignment in social interactions.

According to the prevailing paradigm in social-cognitive neuroscience, the mental states of individuals become shared when they adapt to each other in the pursuit of a shared goal. We challenge this view by proposing an alternative approach to the cognitive foundations of social interactions. The central claim of this paper is that social cognition concerns the graded and dynamic process of alignment of individual minds, even in the absence of a shared goal. When individuals reciprocally exchange information about each other's minds processes of alignment unfold over time and across space, creating a social interaction. Not all cases of joint action involve such reciprocal exchange of information. To understand the nature of social interactions, then, we propose that attention should be focused on the manner in which people align words and thoughts, bodily postures and movements, in order to take one another into account and to make full use of socially relevant information.

Developing a generic approach to online automated analysis of writing and drawing tests in clinical patient profiling.

Writing and drawing tests are widely used in the clinical environment for the diagnosis of a variety of neuropsychological conditions. Conventional assessment of these tests involves the inspection by trained assessors of the completed patient response. This article describes the development of a computer-based framework for data capture, automated feature analysis, and result reporting for a range of drawing- and writing-based test batteries. In developing this framework, we have exploited the commonality between tasks while allowing for both flexibility in configuration across condition-specific testing requirements and extensibility for future test development. Using the two example clinical conditions of visuospatial neglect and dyspraxia, we illustrate the advantages of utilizing a computer-based analysis system, describe a structured approach to system implementation, and demonstrate the generality of this implementation for different conditions of interest, which extends to feature selection and design.

Treatment of "Gamekeeper's Thumb" by reconstruction of the ulnar collateral ligament.

This study examines the treatment of 22 thumbs with symptomatic laxity of the ulnar collateral ligament of the metacarpophalangeal joint by ligament reconstruction 1 week to 10 years after injury. The existing ligament remnants were repaired in 13 thumbs and were re-attached to bone, using a bone anchor, in seven cases. Two ligaments were reconstructed using the extensor pollicis brevis tendon. Patients were reviewed at a mean of 16 months. Functional stability was regained in all patients, but two thumbs had ongoing pain in the metacarpophalangeal joint. All but one patient returned to their original work and recreational pastimes. This study suggests that ligament reconstruction for chronic laxity of the ulnar collateral ligament is likely to achieve painless stability of the metacarpophalangeal joint even when reconstruction is delayed. This makes joint fusion unnecessary in most instances.

A multiexpert framework for character recognition: a novel application of Clifford networks.

A novel multiple-expert framework for recognition of handwritten characters is presented. The proposed framework is composed of multiple classifiers (experts) put together in such a manner as to enhance the recognition capability of the combined network compared to the best performing individual expert participating in the framework. Each of these experts has been derived from a novel neural structure in which the weight values are derived from Clifford algebra. A Clifford algebra is a mathematical paradigm capable of capturing the interdimensional dependencies found in multidimensional data. It offers a technique for concise data storage and processing by representing dependencies between the component dimensions of the data which is otherwise difficult to encode and hence is often employed in analyzing multidimensional data. Results achieved by the proposed multiple-expert framework demonstrates significant improvement over alternative techniques.

Improving ARTMAP learning through variable vigilance.

This paper presents a mechanism to vary the vigilance parameter in the RePART fuzzy neural network. This mechanism helps to smooth out the problem of category proliferation which affects ARTMAP-based networks. Empirical experiments show that the use of variable vigilance improves the performance of the RePART model while, at the same time, requiring a less complex structure.

Computer recording of standard tests of visual neglect in stroke patients.

OBJECTIVE: To determine whether a computer-based method for recording standardized assessment of neglect identifies abnormalities in the 'process' as well as in the 'outcome' of such tasks. DESIGN: Prospective sequential assessment of patients admitted to a stroke rehabilitation unit. SUBJECTS: All consecutive patients with right-sided cerebrovascular accident confirmed on computerized tomography (CT) scan including 30 patients with neglect, 57 patients without neglect. An age-matched control group of 13 subjects. INTERVENTION: All patients were tested using the standard Rivermead Behavioural Inattention Test (BIT) and by computer recording of two standard tests for assessing neglect (line bisection and Albert's test). Age-matched controls were tested using computer recording of the two standard tests. MAIN OUTCOME MEASURES: Neglect was defined using the BIT with a cut-off score of 129. Computer recording measured the 'outcome' of tasks, i.e. the deviation from midline and omissions in cancellation, as well as the 'process' of tasks, i.e. time between cancellations, components of cancellation time including premovement, movement and drawing time, and the starting point for cancellation. RESULTS: The computer recording identified significant differences in 'outcome' and 'process' which distinguished neglect from non-neglect patients. There were significant differences between non-neglect patients and age-matched controls with regard to 'process' measures but not with regard to 'outcome' measures. CONCLUSIONS: Computer recording of standard tests for assessing neglect identifies novel impairments with regard to the process of carrying out tasks. These impairments may be used to investigate changes in neglect with time, the response of neglect to treatment and to explore further the neuropsychological changes associated with neglect in stroke patients.

Developing algorithms to enhance the sensitivity of cancellation tests of visuospatial neglect.

We describe a set of algorithms that enhance the sensitivity of cancellation tests used in assessing visuospatial neglect. The algorithms can be readily implemented on a computer and can provide temporal and nontemporal data on strategies used during cancellation. We also present preliminary results from a group of 68 right-hemisphere brain-damaged patients and 12 age-matched control participants, which demonstrate the clinical significance of the measures we have defined.

Fibrillin-1 in human cartilage: developmental expression and formation of special banded fibers.

The molecular basis for Marfan's syndrome (MS), a heritable disorder of connective tissue, is now known to reside in mutations in FBN1, the gene for fibrillin-1. Classic phenotypic manifestations of MS include several skeletal abnormalities associated primarily with overgrowth of long bones. As a first step towards understanding how mutations in FBN1 result in skeletal abnormalities, the developmental expression of fibrillin-1 (Fib-1) in human skeletal tissues is documented using immunohistochemistry and monoclonal antibodies demonstrated here to be specific for Fib-1. At around 10-11 weeks of fetal gestation, Fib-1 is limited in tissue distribution to the loose connective tissue surrounding skeletal muscle and tendon in developing limbs. By 16 weeks, Fib-1 is widely expressed in developing limbs and digits, especially in the perichondrium, but it is apparently absent within cartilage matrix. Fib-1 appears as a loose meshwork of fibers within cartilage matrix by 20 weeks of fetal gestation. Until early adolescence, Fib-1 forms loose bundles of microfibrils within cartilage. However, by late adolescence, broad banded fibers composed of Fib-1 are found accumulated pericellularly within cartilage. Because these fibers can be extracted from cartilage using dissociative conditions, we postulate that they are laterally packed and crosslinked microfibrils. On the basis of these findings, we suggest that the growth-regulating function of Fib-1 may reside persistently within the perichondrium. In addition, the accumulation of special laterally crosslinked Fib-1 microfibrils around chondrocytes during late adolescence suggests that growth-regulating activities may also be performed by Fib-1 at these sites.

Evaluation of the immunotoxicity of benzoporphyrin derivative (BPD-MA) in mice.

Photodynamic therapy has been shown to selectively eliminate activated lymphocytes in a number of experimental situations. These findings have important implications in therapies involving selective immunomodulation. In this study we report the effects of intravenous dosing with the photosensitizer benzoporphyrin derivative-monoacid A(BPD) on normal immunological function. Therapeutic doses of BPD and light had no effect on natural killer cell activity, the mixed lymphocyte reaction, cell-mediated lympholysis, the primary immune response to sheep red blood cells, or the secondary memory response to T cell-dependent antigens. In non-light treated controls, BPD at concentrations up to 10-fold higher had a limited effect on cell-mediated lympholysis. We conclude that the primary effect of BPD in several therapeutic modalities in not due to a generalized suppression of the immune system.

The function of below-knee amputee versus the patient with salvaged grade III tibial fracture.

This retrospective study compares the end-stage function of the traumatic below-knee amputee with that of the patient with salvaged Grade III tibial fracture. Twenty-four patients, 12 below-knee amputees and 12 with salvaged tibiae, were interviewed and examined one year or more after the completion of treatment. Emphasis was on function of the limb, the patient, and the quality of life. The early amputees had higher scores, fewer operations, and six-week hospitalization on average, and returned to work and sport within six months. Neither the amputees, nor the salvaged group, functioned entirely normally. Most patients made significant alterations to work and sporting activities, and approximately one third believed there was deterioration in the quality of life. These results suggest that amputation should be strongly considered when confronted with a borderline salvageable tibial injury or prolonged salvage attempts.

Carbon dioxide laser surgery for skin disease.

Since it was developed in the 1960s, the carbon dioxide (CO2) laser has had an important role in the practice of dermatology. The CO2 laser has some advantages over conventional techniques used in dermatologic surgical treatment. It routinely provides a bloodless surgical field as well as unusual surgical precision. Although the CO2 laser is specifically indicated for certain conditions, in other situations, only marginal benefit may be noted in comparison with standard techniques such as scalpel surgical procedures, dermabrasion, cryosurgery, and electrosurgery. In this article, we briefly review the history and physics of the CO2 laser, its operation, and safety principles and discuss dermatologic conditions that are treated with the CO2 laser. We also describe 8 representative cases from our experience with more than 800 cases of CO2 laser treatment in the practice of dermatology at the Mayo Clinic since 1986.

Computer-assisted analysis of the echocardiogram in the clinical environment.

Ultrasound imaging of the heart can provide an important source of diagnostic data to the cardiologist, but conventional echocardiography requires considerable expertise, and is extremely time-consuming. Computer-based analysis is therefore very attractive and, in the light of decreasing hardware costs in recent years, has become increasingly viable in practice. This paper describes the specification and implementation of a computer-based tool which supports the clinician in the analysis of echocardiograms, exploiting the clinical judgement and inherent skill of the clinician. The design of the system has focused particularly on the provision of a powerful user interface for ease of interaction, flexibility in system functionality, and extensive interactive capabilities to maximize reliability and convenience of use. This paper will describe the principal features of the system and illustrate its use in the clinical environment.

Expression of an EL4 tumour-associated determinant on subpopulations of murine T cells in normal and lympho-proliferative autoimmune mice.

It has been demonstrated that the single autosomal recessive lpr and gld genes are responsible for the accumulation of unusual T-cell subsets. Although these subsets have been assigned to the T-cell lineage, they share certain antigenic cell surface markers with mature B lymphocytes. Consequently the maturational pathway(s) of these cells has been difficult to fit in the currently accepted models of T-cell differentiation. Previous work has determined that the YE1/19.1 monoclonal antibody (mAb), developed against the EL4 tumour line, reacts with the accumulating T cells in lpr-expressing mice. In this study we report that YE1/19.1 could also be used as a marker for the accumulating T cells in gld-expressing mice and that the hyporesponsiveness seen in gld mice correlated with these accumulating cells. We then demonstrated that the YE1/19.1 antibody also reacts with a subpopulation of neonatal thymocytes as well as a mitogen non-responsive subpopulation of 'double negative' T cells from the spleens and thymuses of non-autoimmune mice. Our findings indicate that the YE1/19.1 mAb will be a useful probe for helping in the eludication of the intra-thymic maturational pathways of T lymphocytes.

Characteristics of user interaction with a communication system for the non-vocal using a hierarchically structured interface.

This paper describes aspects of a highly flexible communication aid for the non-vocal which, as a principal feature, allows the local specification of a selected communication vocabulary so as to match the requirements of an individual communicator. The paper describes and discusses the structure of a hierarchically configured interface through which this vocabulary specification may be achieved in an efficient and convenient manner, greatly increasing the range of applicability of such a communication aid.

A model-based approach to the specification of computer-based communication aids.

This paper describes and discusses a strategy for the design of an expressive communication aid for the non-vocal which is highly flexible and which embodies the principle of user-specifiable function. Some of the implications which arise when an intuitively common system configuration is adopted in practice are examined. It is shown that a principal feature of the design process and subsequent assessment of the system is the way in which modelling of processes, mechanisms or functions provides a common focus for establishing the important criteria for system design and evaluation of its applicability.

An evaluation of the information interface in the design of computer-driven aids for expressive communication.

Computer-based systems as assistive aids for expressive communication have become increasingly sophisticated. One such system, which provides great flexibility in the specification of an operational configuration and which is highly user-oriented in its design, is discussed here. In particular, attention is directed towards the relationship between the physical signals which constitute the representation of graphic-symbol communication units and the transfer of conceptual information which these symbols ultimately mediate. This relationship is investigated practically with a view to establishing a connection between operational criteria at the functional level and the supporting physical infrastructure at the computational level. This investigation leads to some conclusions not only in terms of design strategy for flexible communication aids, but points to issues of broader significance in the area of computer-based assistive devices for those with special needs.

Detection of malignant melanoma with monoclonal antibodies.

Eleven murine monoclonal antibodies (MoAbs) were isolated that defined unique membrane antigens expressed on human melanoma cells but not detectable on human lymphoid cells by radioimmunometric assays. Five of these MoAbs each identified a separate melanoma cell surface antigen as shown by distinctly different in vitro MoAb binding patterns to a diverse panel of tumor cell lines. One of these 5 monoclonals, MoAb 34.1, reacted specifically with 9/11 melanoma lines and 0/28 other human tumor or lymphoid cell lines. The other 4 MoAbs reacted strongly with melanomas, but also bound to 1 or more non-melanoma lines. The remaining 6 MoAbs defined three distinct regions of a single melanoma cell membrane protein with a molecular weight of 125 kiloDaltons (kD) as shown by antibody crossblocking and gel electrophoresis. A sensitive radioimmunoassay developed with MoAbs to 2 epitopes of this 125 kD protein detected up to 500-fold higher levels of this antigen in extracts of melanoma cells compared to autologous lymphoid cells. The 125 kD antigen also was detected by indirect immunoperoxidase assays with the MoAbs on biopsied tumors in histologic tissue sections of 5/11 metastatic melanomas and 1/11 carcinomas but was found on some normal endothelium and smooth muscle. Another monoclonal, MoAb 705, reacted more broadly with tumor cells in 10/14 biopsied melanomas and 10/11 carcinomas, but also was reactive with basal epidermis and normal fibroblasts. By contrast, MoAb 34.1 bound specifically to tumor cells of 7/11 biopsied metastatic melanomas, but bound 0/10 carcinomas and few normal tissues except for some macrophages. Thus, MoAb 34.1 was the most specific diagnostic reagent for immunohistologic detection of melanoma. The 250 kD antigen defined by MoAb 34.1 is similar to a high molecular weight proteoglycan reported to be an excellent tumor marker for human melanomas. The results of these studies show that murine monoclonal antibodies can be used as sensitive reagents for radioimmunoassays and immunohistology of malignant melanoma.