327 research outputs found

    Blinded by magic: eye-movements reveal the misdirection of attention

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    Recent studies (e.g., Kuhn & Tatler, 2005) have suggested that magic tricks can provide a powerful and compelling domain for the study of attention and perception. In particular, many stage illusions involve attentional misdirection, guiding the observer’s gaze to a salient object or event, while another critical action, such as sleight of hand, is taking place. Even if the critical action takes place in full view, people typically fail to see it due to inattentional blindness. In an eye-tracking experiment, participants watched videos of a new magic trick, wherein a coin placed beneath a napkin disappears, reappearing under a different napkin. Appropriately deployed attention would allow participants to detect the secret event that underlies the illusion (a moving coin), as it happens in full view and is visible for approximately 550 ms. Nevertheless, we observed high rates of inattentional blindness. Unlike prior research, eye-movements during the critical event showed different patterns for participants, depending upon whether they saw the moving coin. The results also showed that when participants watched several practice videos without any moving coin, they became far more likely to detect the coin in the critical trial. Taken together, the findings are consistent with perceptual load theory (Lavie & Tsal, 1994)

    From chemotherapy to targeted treatment

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    Today, melanoma is considered as a spectrum of melanocytic malignancies that can be characterized by clinical and molecular features, including targetable mutations in several kinases. The successful development of therapies, targeting mutated BRaF (v-raf murine sarcoma viral oncogene homolog B1) or c-KIT (v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog), has resulted in new treatment options including vemurafenib, imatinib and mitogen-activated protein kinase inhibitors. These molecules are selected if the respective mutation is present. after this first progress in the treatment of advanced melanoma, there is expectation that combinations of kinase inhibitor will additionally improve the overall survival rates and progression-free survival in advanced melanom

    Microsaccades reflect the dynamics of misdirected attention in magic

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    The methods of magicians provide powerful tools for enhancing the ecological validity of laboratory studies of attention. The current research borrows a technique from magic to explore the relationship between microsaccades and covert attention under near-natural viewing conditions. We monitored participants’ eye movements as they viewed a magic trick where a coin placed beneath a napkin vanishes and reappears beneath another napkin. Many participants fail to see the coin move from one location to the other the first time around, thanks to the magician’s misdirection. However, previous research was unable to distinguish whether or not participants were fooled based on their eye movements. Here, we set out to determine if microsaccades may provide a window into the efficacy of the magician’s misdirection. In a multi-trial setting, participants monitored the location of the coin (which changed positions in half of the trials), while engaging in a delayed match-to-sample task at a different spatial location. Microsaccades onset times varied with task difficulty, and microsaccade directions indexed the locus of covert attention. Our com-bined results indicate that microsaccades may be a useful metric of covert attentional processes in applied and ecologically valid settings

    Limited value of 18F-FDG PET/CT and S-100B tumour marker in the detection of liver metastases from uveal melanoma compared to liver metastases from cutaneous melanoma

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    Purpose: The objective of this study was to evaluate the value of 18F-FDG PET/CT and S-100B tumour marker for the detection of liver metastases from uveal melanoma in comparison to liver metastases from cutaneous melanoma. Methods: A retrospective evaluation was conducted of 27 liver metastases in 13 patients with uveal melanoma (UM) (mean age: 56.8, range: 30-77) and 43 liver metastases in 14 patients (mean age: 57.9, range: 40-82) with cutaneous melanoma (CM) regarding size and FDG uptake by measuring the maximum standardized uptake value (SUVmax). S-100B serum tumour markers were available in 20 patients. Cytology, histology, additional morphological imaging and follow-up served as reference standard. In nine patients liver metastases were further evaluated histologically regarding GLUT-1 and S-100 receptor expression and regarding epithelial or spindle cell growth pattern. Results: Of 27 liver metastases in 6 of 13 patients (46%) with UM, 16 (59%) were FDG negative, whereas all liver metastases from CM were positive. Liver metastases from UM showed significantly (p < 0.001) lower SUVmax (mean: 3.5, range: 1.5-13.4) compared with liver metastases from CM (mean: 6.6, range: 2.3-15.3). In four of six (66.7%) patients with UM and liver metastases S-100B was normal and in two (33.3%) increased. All PET-negative liver metastases were detectable by morphological imaging (CT or MRI). S-100B was abnormal in 13 of 14 patients with liver metastases from CM. S-100B values were significantly higher (p = 0.007) in the CM patient group (mean S-100B: 10.9μg/l, range: 0.1-115μg/l) compared with the UM patients (mean: 0.2μg/l, range: 0.0-0.5μg/l). Histological work-up of the liver metastases showed no obvious difference in GLUT-1 or S-100 expression between UM and CM liver metastases. The minority (36%) of patients with UM had extrahepatic metastases and the majority (86%) of patients with CM had extrahepatic metastases, respectively. There was a close to significant trend to better survival of UM patients compared with CM patients (p = 0.06). Conclusion: FDG PET/CT and serum S-100B are not sensitive enough for the detection of liver metastases from UM, whereas liver metastases from cutaneous melanoma are reliably FDG positive and lead regularly to increased S-100B tumour markers. The reason for the lower FDG uptake in UM liver metastases remains unclear. We recommend to perform combined contrast-enhanced PET/CT in order to detect FDG-negative liver metastases from U

    First-line temozolomide combined with bevacizumab in metastatic melanoma: a multicentre phase II trial (SAKK 50/07)

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    Background: Oral temozolomide has shown similar efficacy to dacarbazine in phase III trials with median progression-free survival (PFS) of 2.1 months. Bevacizumab has an inhibitory effect on the proliferation of melanoma and sprouting endothelial cells. We evaluated the addition of bevacizumab to temozolomide to improve efficacy in stage IV melanoma. Patients and methods: Previously untreated metastatic melanoma patients with Eastern Cooperative Oncology Group performance status of two or more were treated with temozolomide 150 mg/m2 days 1-7 orally and bevacizumab 10 mg/kg body weight i.v. day 1 every 2 weeks until disease progression or unacceptable toxicity. The primary end point was disease stabilisation rate [complete response (CR), partial response (PR) or stable disease (SD)] at week 12 (DSR12); secondary end points were best overall response, PFS, overall survival (OS) and adverse events. Results: Sixty-two patients (median age 59 years) enrolled at nine Swiss centres. DSR12 was 52% (PR: 10 patients and SD: 22 patients). Confirmed overall response rate was 16.1% (CR: 1 patient and PR: 9 patients). Median PFS and OS were 4.2 and 9.6 months. OS (12.0 versus 9.2 months; P = 0.014) was higher in BRAF V600E wild-type patients. Conclusions: The primary end point was surpassed showing promising activity of this bevacizumab/temozolomide combination with a favourable toxicity profile. Response and OS were significantly higher in BRAF wild-type patient

    Offscreen and in the chair next to your: conversational agents speaking through actual human bodies

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    his paper demonstrates how to interact with a conversational agent that speaks through an actual human body face-to-face and in person (i.e., offscreen). This is made possible by the cyranoid method: a technique involving a human person speech shadowing for a remote third-party (i.e., receiving their words via a covert audio-relay apparatus and repeating them aloud in real-time). When a person shadows for an artificial conversational agent source, we call the resulting hybrid an “echoborg.” We report a study in which people encountered conversational agents either through a human shadower face-to-face or via a text interface under conditions where they assumed their interlocutor to be an actual person. Our results show that the perception of a conversational agent is dramatically altered when the agent is voiced by an actual, tangible person. We discuss the potential implications this methodology has for the development of conversational agents and general person perception research

    Analysis of BRAF and NRAS Mutation Status in Advanced Melanoma Patients Treated with Anti-CTLA-4 Antibodies: Association with Overall Survival?

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    Ipilimumab and tremelimumab are human monoclonal antibodies (Abs) against cytotoxic T-lymphocyte antigen-4 (CTLA-4). Ipilimumab was the first agent to show a statistically significant benefit in overall survival in advanced melanoma patients. Currently, there is no proven association between the BRAFV600 mutation and the disease control rate in response to ipilimumab. This analysis was carried out to assess if BRAFV600 and NRAS mutation status affects the clinical outcome of anti-CTLA-4-treated melanoma patients. This is a retrospective multi-center analysis of 101 patients, with confirmed BRAF and NRAS mutation status, treated with anti-CTLA-4 antibodies from December 2006 until August 2012. The median overall survival, defined from the treatment start date with the anti-CTLA-4. Abs-treatment to death or till last follow up, of BRAFV600 or NRAS mutant patients (n = 62) was 10.12 months (95% CI 6.78-13.2) compared to 8.26 months (95% CI 6.02-19.9) in BRAFV600/NRASwt subpopulation (n = 39) (p = 0.67). The median OS of NRAS mutated patients (n = 24) was 12.1 months and although was prolonged compared to the median OS of BRAF mutated patients (n = 38, mOS = 8.03 months) or BRAFV600/NRASwt patients (n = 39, mOS = 8.26 months) the difference didn't reach statistical significance (p = 0.56). 69 patients were able to complete 4 cycles of anti-CTLA-4 treatment. Of the 24 patients treated with selected BRAF- or MEK-inhibitors, 16 patients received anti-CTLA 4 Abs following either a BRAF or MEK inhibitor with only 8 of them being able to finish 4 cycles of treatment. Based on our results, there is no difference in the median OS in patients treated with anti-CTLA-4 Abs implying that the BRAF/NRAS mutation status alone is not sufficient to predict the outcome of patients treated with anti-CTLA-4 Abs

    Radiosensitization by BRAF inhibitor therapy—mechanism and frequency of toxicity in melanoma patients

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    This study shows radiosensitization by BRAF inhibitors in clinical practice and ex vivo by fluorescence in situ hybridization of chromosomal breaks. Nevertheless, radiotherapy with concomitant BRAF inhibitor therapy is feasible with an acceptable increase in toxicity. Vemurafenib is a more potent radiosensitizer than dabrafenib in both the patient study and the ex vivo experiment
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