Innate and learned components of human visual preference. (1/245)

BACKGROUND: Recent claims in neuroscience and evolutionary biology suggest that the aesthetic sense reflects preferences for image signals whose characteristics best fit innate brain mechanisms of visual recognition. RESULTS: This hypothesis was tested by behaviourally measuring, for a set of initially unfamiliar images, the effects of category learning on preference judgements by humans, and by relating the observed data to computationally reconstructed internal representations of categorical concepts. Category learning induced complex shifts in preference behaviour. Two distinct factors - complexity and bilateral symmetry - could be identified from the data as determinants of preference judgements. The effect of the complexity factor varied with object knowledge acquired through category learning. In contrast, the impact of the symmetry factor proved to be unaffected by learning experience. Computer simulations suggested that the preference for pattern complexity relies on active (top-down) mechanisms of visual recognition, whereas the preference for pattern symmetry depends on automatic (bottom-up) mechanisms. CONCLUSIONS: Human visual preferences are not fully determined by (objective) structural regularities of image stimuli but also depend on their learned (subjective) interpretation. These two aspects are reflected in distinct complementary factors underlying preference judgements, and may be related to complementary modes of visual processing in the brain.  (+info)

Activation of the right inferior frontal cortex during assessment of facial emotion. (2/245)

We measured regional cerebral blood flow (rCBF) using positron emission tomography (PET) to determine which brain regions are involved in the assessment of facial emotion. We asked right-handed normal subjects to assess the signalers' emotional state based on facial gestures and to assess the facial attractiveness, as well as to discriminate the background color of the facial stimuli, and compared the activity produced by each condition. The right inferior frontal cortex showed significant activation during the assessment of facial emotion in comparison with the other two tests. The activated area was located within a triangular area of the inferior frontal cortex in the right cerebral hemisphere. These results, together with those of previous imaging and clinical studies, suggest that the right inferior frontal cortex processes emotional communicative signals that could be visual or auditory and that there is a hemispheric asymmetry in the inferior frontal cortex in relation to the processing of emotional communicative signals.  (+info)

How Do head and neck cancer patients prioritize treatment outcomes before initiating treatment? (3/245)

PURPOSE: To determine, pretreatment, how head and neck cancer (HNC) patients prioritize potential treatment effects in relationship to each other and to survival and to ascertain whether patients' preferences are related to demographic or disease characteristics, performance status, or quality of life (QOL). PATIENTS AND METHODS: One hundred thirty-one patients were assessed pretreatment using standardized measures of QOL (Functional Assessment of Cancer Therapy-Head and Neck) and performance (Performance Status Scale for Head and Neck Cancer). Patients were also asked to rank a series of 12 potential HNC treatment effects. RESULTS: Being cured was ranked top priority by 75% of patients; another 18% ranked it second or third. Living as long as possible and having no pain were placed in the top three by 56% and 35% of patients, respectively. Items that were ranked in the top three by 10% to 24% of patients included those related to energy, swallowing, voice, and appearance. Items related to chewing, being understood, tasting, and dry mouth were placed in the top three by less than 10% of patients. Excluding the top three rankings, there was considerable variability in ratings. Rankings were generally unrelated to patient or disease characteristics, with the exception that cure and living were of slightly lower priority and pain of higher priority to older patients compared with younger patients. CONCLUSION: The data suggest that, at least pretreatment, survival is of primary importance to patients, supporting the development of aggressive treatment strategies. In addition, results highlight individual variability and warn against making assumptions about patients' attitudes vis-a-vis potential outcomes. Whether patients' priorities will change as they experience late effects is currently under investigation.  (+info)

Measuring the quality of life in patients with venous ulcers. (4/245)

PURPOSE: This prospective study aimed to validate a newly designed specific measure of quality of life for patients with venous ulcers. METHODS: The study was set in a London teaching hospital and surrounding community clinics. Items for the questionnaire were selected by means of patient interviews, a literature review, and expert opinion. The questionnaire and the Short Form 36-item (SF-36) Health Survey were given to a prospective consecutive cohort of 98 patients with proven venous ulcers that were diagnosed by means of clinical and color duplex examination. Fifty-eight of the patients were women (60%), and the median age of patients was 76 years. The questionnaire was assessed for reliability, validity, and responsiveness. RESULTS: The ulcer-specific questionnaire showed good reliability, as assessed by means of the internal consistency (Cronbach alpha = 0.93) and test-retest analysis (r = 0.84). Factor analysis identified four important health factors: social function, domestic activities, cosmesis, and emotional status. Validity was demonstrated by means of a high correlation with all eight domains of the SF-36 general health measure (r > 0.55, P <.001). Responsiveness was demonstrated by means of a significant reduction in the score on the ulcer questionnaire as ulcers healed at 6 and 11 weeks (P <.05). CONCLUSION: Good evidence exists that a clinically derived measure for patients with venous ulcers has validity to measure the quality of life.  (+info)

American College of Cardiology/European Society of Cardiology International Study of Angiographic Data Compression Phase III: measurement of image quality differences at varying levels of data compression. (5/245)

OBJECTIVES: We sought to investigate up to which level of Joint Photographic Experts Group JPEG) data compression the perceived image quality and the detection of diagnostic features remain equivalent to the quality and detectability found in uncompressed coronary angiograms. BACKGROUND: Digital coronary angiograms represent an enormous amount of data and therefore require costly computerized communication and archiving systems. Earlier studies on the viability of medical image compression were not fully conclusive. METHODS: Twenty-one raters evaluated sets of 91 cine runs. Uncompressed and compressed versions of the images were presented side by side on one monitor, and image quality differences were assessed on a scale featuring six scores. In addition, the raters had to detect pre-defined clinical features. Compression ratios (CR) were 6:1, 10:1 and 16:1. Statistical evaluation was based on descriptive statistics and on the equivalence t-test. RESULTS: At the lowest CR (CR 6:1), there was already a small (15%) increase in assigning the aesthetic quality score indicating "quality difference is barely discernible-the images are equivalent." At CR 10:1 and CR 16:1, close to 10% and 55%, respectively, of the compressed images were rated to be "clearly degraded, but still adequate for clinical use" or worse. Concerning diagnostic features, at CR 10:1 and CR 16:1 the error rate was 9.6% and 13.1%, respectively, compared with 9% for the baseline error rate in uncompressed images. CONCLUSIONS: Compression at CR 6:1 provides equivalence with the original cine runs. If CR 16:1 were used, one would have to tolerate a significant increase in the diagnostic error rate over the baseline error rate. At CR 10:1, intermediate results were obtained.  (+info)

Treatment outcome in cleft lip and palate: issues and perspectives. (6/245)

In the last 40 years, great progress has been made toward a better understanding of many aspects of the cleft lip and palate defect, but there is still a long way to go before there is agreement on the optimal treatment procedures. With regard to the primary operations, it can be stated, in a somewhat simplified form, that there are two main schools of thought in cleft treatment. One advocates early closure of the lip and palate, a procedure which imparts a high priority to early speech function. The other recommends delayed closure of the hard palate, thereby according a high priority to the growth of the maxilla. A number of intercenter and multicenter studies have been carried out recently in an effort to elucidate which procedures give the best result, both esthetically and functionally. The results are ambiguous, and this has led a number of researchers to suggest that the randomized clinical trial is the only way to resolve the ambiguity. The fact that it has proved difficult to identify the optimal procedures in the field of cleft lip and palate treatment need not only be due to a less than optimal research design; a contributory factor might also be the great variability in craniofacial morphology and in the response to treatment in patients who have exactly the same cleft lip and palate diagnosis. Intensive research has made it possible to state categorically that clefts occur due to many different factors in an interplay between genetics and environment. Therefore, it is not likely that a single gene can be responsible for clefting. Since scar tissue presents many problems-for instance, impairment of growth-the reduction or prevention of scar formation has long been a desirable goal. The discovery that a fetus can heal without scar formation has led to many animal experiments. The timing of the surgical intervention on fetuses is critical, since late-gestation fetuses heal with adult-like scarring. There are still many unsolved problems connected with fetal surgery, and at present prenatal surgery for repair of cleft lip and palate is not ethically defensible in humans. On the other hand, it appears that there are considerable possibilities for the reduction of human scarring after surgery with the introduction of various wound-healing medications.  (+info)

Open bite: stability after bimaxillary surgery--2-year treatment outcomes in 58 patients. (7/245)

Stability after bimaxillary surgery to correct open bite malocclusion and mandibular retrognathism was evaluated on lateral cephalograms before surgery, 8 weeks post-operatively, and after 2 years. The 58 consecutive patients were treated to a normal occlusion and good facial aesthetics. Treatment included the orthodontic alignment of teeth by maxillary and mandibular fixed appliances, Le Fort I osteotomy, and bilateral sagittal split ramus osteotomy. Twenty-six patients also had a genioplasty. Intra-osseous wires or bicortical screws were used for fixation. Twenty-three patients had maxillo-mandibular fixation (MMF) for 8 weeks or more, six for 4-7 weeks, 14 for 1-3 weeks, and 15 had no fixation. At follow-up 2 years later, the maxilla remained unchanged and the mandible had rotated on average 1.4 degrees posteriorly. Seventeen patients had an open bite. Among them, eight patients had undergone segmental osteotomies. The relapse was mainly due to incisor proclination. The most stabile overbite was found in the group with no MMF after surgery.  (+info)

The rhomboid flap in medial canthal reconstruction. (8/245)

AIM: To describe a series of patients who have undergone a medial canthal reconstruction with a rhomboid flap. METHODS: A non-comparative interventional case series of 27 patients with medial canthal defects after Mohs excision of medial canthal basal cell carcinomas who underwent reconstruction using a rhomboid-shaped transpositional flap of adjoining skin and subcutaneous tissue. 25 cases were performed under local anaesthesia. The remaining two cases were combined with major lid reconstruction and performed under general anaesthesia. The outcome measures were closure of the defect, the cosmetic result, complications, and re-operations. RESULTS: Primary closure of the defect was achieved in all cases. The cosmetic result was highly satisfactory in all cases. There were no major complications or re-operations. Two cases had minor webbing of the medial upper lid. CONCLUSIONS: The rhomboid flap is an effective, quick, and simple technique for medial canthal reconstruction. It provides excellent cosmesis and is associated with minimal complications. It can be modified according to the nature of the periorbital skin and the location, size, and depth of the defect.  (+info)