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81.
While it has been claimed that the ventral visual stream ends in the inferior aspects of the anterior temporal lobe (ATL), little is known about whether this region is important for visual perception. Here the performance of two patients with unilateral ATL damage was assessed across four visual perception tasks that parametrically varied stimulus similarity. Patients performed normally on difficult judgments of circle size or face age but were impaired on face identity and dot pattern matching tasks. Portions of the ATL, most likely the ventral surface, may have a functional role in visual perception tasks requiring detailed configural processing, most commonly used to discern facial identity.  相似文献   
82.
Isolating processes within the brain that are specific to human behavior is a key goal for social neuroscience. The current research was an attempt to test whether recent findings of enhanced negative ERPs in response to unexpected human gaze are unique to eye gaze stimuli by comparing the effects of gaze cues with the effects of an arrow cue. ERPs were recorded while participants (N = 30) observed a virtual actor or an arrow that gazed (or pointed) either toward (object congruent) or away from (object incongruent) a flashing checkerboard. An enhanced negative ERP (N300) in response to object incongruent compared to object congruent trials was recorded for both eye gaze and arrow stimuli. The findings are interpreted as reflecting a domain general mechanism for detecting unexpected events.  相似文献   
83.
The N170 event-related potential (ERP) component differentiates faces from non-faces, but studies aimed at investigating whether the processing indexed by this component is also sensitive to racial differences among faces have garnered conflicting results. Here, we explore how task affects the influence of race on the N170 among White participants. N170s were larger to ingroup White faces than outgroup Black faces, but only for those required to attend to race, suggesting that attention to race can result in deeper levels of processing for ingroup members. Conversely, N170s were larger to Black faces than White faces for participants who attended to the unique identity of the faces, suggesting that attention to identity can result in preferential recruitment of cognitive resources for outgroup members. Taken together, these findings suggest that race can differentially impact face processing at early stages of encoding, but differences in processing are contingent upon one’s goal state.  相似文献   
84.
目的探讨轻度认知障碍患者早期面孔知觉加工过程中N170效应与N170翻转效应。方法采用配伍组设计从潍坊潍柴社区退休职工中选取受试对象,刺激程序使用stim2软件编写,采用美国Neuroscan公司脑电信号采集记录仪记录脑电后进行离线分析并用SPSS18.0进行统计学分析。结果①MCI组与对照组均产生了明显的颞枕区分布的面孔特异性成分N170,且MCI组非靶刺激诱发的N170波幅比对照组降低(P<0.001),潜伏期延长(P<0.05)。②MCI组和正常老年人均产生N170效应(Nd170)以及N170翻转效应。结论 MCI患者存在早期面孔知觉加工障碍,可能发生在面孔基本分类水平,而结构信息的早期加工尚保持正常。  相似文献   
85.
Vascularized composite tissue allotransplantation is a viable treatment option for injuries and defects that involve multiple layers of functional tissue. In the past 15 yr, more than 150 vascularized composite allotransplantation (VCA) surgeries have been reported for various anatomic locations including – but not limited to – trachea, larynx, abdominal wall, face, and upper and lower extremities. VCA can achieve a level of esthetic and functional restoration that is currently unattainable using conventional reconstructive techniques. Although the risks of lifelong immunosuppression continue to be an important factor when evaluating the benefits of VCA, reported short‐ and long‐term outcomes have been excellent, thus far. Acute rejections are common in the early post‐operative period, and immunosuppression‐related side effects have been manageable. A multidisciplinary approach to the management of VCA has proven successful. Reports of long‐term graft losses have been rare, while several factors may play a role in the pathophysiology of chronic graft deterioration in VCA. Alternative approaches to immunosuppression such as cellular therapies and immunomodulation hold promise, although their role is so far not defined. Experimental protocols for VCA are currently being explored. Moving forward, it will be exciting to see whether VCA‐specific aspects of allorecognition and immune responses will be able to help facilitate tolerance induction.  相似文献   
86.
Procurement of a facial vascularized composite allograft (VCA) should allow concurrent procurement of all solid organs and ensure their integrity. Because full facial procurement is time–intensive, “simultaneous–start” procurement could entail VCA ischemia over 12 h. We procured a total face osteomyocutaneous VCA from a brain–dead donor. Bedside tracheostomy and facial mask impression were performed preoperative day 1. Solid organ recovery included heart, lungs, liver, kidneys, and pancreas. Facial dissection time was 12 h over 15 h to diminish ischemia while awaiting recipient preparation. Solid organ recovery began at 13.5 h, during midfacial osteotomies, and concluded immediately after facial explantation. Facial thoracic and abdominal teams worked concurrently. Estimated blood loss was 1300 mL, requiring five units of pRBC and two units FFP. Urine output, MAP, pH and PaO2 remained normal. All organs had good postoperative function. We propose an algorithm that allows “face first, concurrent completion” recovery of a complex facial VCA by planning multiple pathways to expedient recovery of vital organs in the event of clinical instability. Beginning the recipient operation earlier may reduce waiting time due to extensive recipient scarring causing difficult dissection.  相似文献   
87.
Background: Current research in theoretical linguistics, experimental psychology, and clinical aphasiology suggests that adjective training may facilitate unique aspects of language production and functional communication in persons with aphasia. Although considerable research has been devoted to treatments targeting nouns and verbs, there has been relatively little treatment research directed towards adjectives.

Aims: The goal of this study was to further investigate the viability of adjective training in aphasia by applying an integrated treatment approach targeting adjective production in the context of single word, sentence, and discourse levels of communication. Specific objectives were to quantify baseline adjective production, acquisition of target structures, and treatment generalisation effects.

Method: A single-participant multiple-baseline design was used to evaluate treatment effects in three individuals with nonfluent chronic aphasia. A battery of experimental measures and standardised tests was also administered pre- and post-treatment to assess baseline performance and generalisation effects extending to adjectives, other parts of speech, sentence processing, and discourse production.

Outcomes & Results: Two of the three participants acquired the target structures and maintained criterion performance levels 1 month after treatment. In spite of differences in baseline performance and responsiveness to treatment, all three participants demonstrated significant gains on standardised measures of language production.

Conclusions: Findings add to existing literature supporting the viability of adjective training for individuals with aphasia. Participant characteristics and treatment factors that may contribute to variable outcomes are also discussed.  相似文献   
88.
The classic view holds that the medial temporal lobes (MTL) are dedicated to declarative memory functioning. Recent evidence, however, suggests that perirhinal cortex (PrC), a structure within the anterior MTL, may also play a role in perceptual discriminations when representations of complex conjunctions of features, or of gestalt‐characteristics of objects must be generated. Interestingly, neuroimaging and electrophysiological recordings in nonhuman primates have also revealed a face patch in the anterior collateral sulcus with preferential responses to face stimuli in various task contexts. In the present fMRI study, we investigated the representational demands that influence PrC involvement in different types of judgments on human faces. Holding stimulus complexity constant, we independently manipulated the nature of the task and the orientation of the stimuli presented (through face inversion). Aspects of right PrC showed increased responses in a forced‐choice recognition‐memory and a perceptual‐oddity task, as compared to a feature‐search task that was included to probe visual detection of an isolated face feature. Effects of stimulus orientation in right PrC were observed when the recognition‐memory condition for upright faces was compared with all other experimental conditions, including recognition‐memory for inverted faces‐a result that can be related to past work on the role of PrC in object unitization. Notably, both effects in right PrC paralleled activity patterns in broader networks of regions that also included the right fusiform gyrus and the amygdala, regions frequently implicated in face processing in prior research. As such, the current findings do not support the view that reference to a prior study episode clearly distinguishes the role of PrC from that of more posterior ventral visual pathway regions. They add to a growing body of evidence suggesting that the functional role of specific MTL structures may be best understood in terms of the representations that are required by the task and the stimuli at hand. © 2013 Wiley Periodicals, Inc.  相似文献   
89.
Objective: To assess the relationship between copay amount and vaccination claim submission status for tetanus-diphtheria-acellular pertussis (Tdap) and herpes zoster (GSK study identifier: HO-14-14319).

Methods: Retrospective analyses were performed using vaccination administrative claims data in patients aged ≥65 years with ≥1 claim for Tdap or zoster vaccines between 2012 and 2014. To avoid confounding by other financial responsibility, analyses were conducted among patients in the copayment phase of insurance. The impact of patient copay amount on vaccination claim status (“canceled” vs. “paid”) was evaluated by logistic regression separately for Tdap and zoster, adjusting for patient and provider characteristics.

Results: A total of 81,027 (39.2% with canceled claims) and 346,417 patients (56.8% with canceled claims) were included in the Tdap and zoster analyses, respectively. Mean (standard deviation) copay for canceled vs. paid claims was $37.2 (18.4) vs. $31.1 (20.1) for Tdap and $64.9 (36.9) vs. $53.5 (38.8) for zoster. The adjusted odds ratios (ORs) for a canceled Tdap vaccine claim, compared with Objective: To assess the relationship between copay amount and vaccination claim submission status for tetanus-diphtheria-acellular pertussis (Tdap) and herpes zoster (GSK study identifier: HO-14-14319).

Methods: Retrospective analyses were performed using vaccination administrative claims data in patients aged ≥65 years with ≥1 claim for Tdap or zoster vaccines between 2012 and 2014. To avoid confounding by other financial responsibility, analyses were conducted among patients in the copayment phase of insurance. The impact of patient copay amount on vaccination claim status (“canceled” vs. “paid”) was evaluated by logistic regression separately for Tdap and zoster, adjusting for patient and provider characteristics.

Results: A total of 81,027 (39.2% with canceled claims) and 346,417 patients (56.8% with canceled claims) were included in the Tdap and zoster analyses, respectively. Mean (standard deviation) copay for canceled vs. paid claims was $37.2 (18.4) vs. $31.1 (20.1) for Tdap and $64.9 (36.9) vs. $53.5 (38.8) for zoster. The adjusted odds ratios (ORs) for a canceled Tdap vaccine claim, compared with $0 copay, were 1.19 ($1–25 copay), 1.76 ($26–50 copay), 2.42 ($51–75 copay) and 2.40 ($76–100 copay), all p?<?.001. The adjusted ORs for a canceled zoster vaccine claim, compared with $0 copay, were 1.02 ($1–25), 1.39 ($26–50), 1.66 ($51–75), 2.07 ($76–100) and 2.71 (>$100), all p?<?.001 except for $1–25 (p?=?.172).

Conclusions: High patient copay is a barrier to Tdap and zoster vaccinations in Medicare Part D patients. Providing vaccines at low or no copay may improve vaccination rates in these adults.

GSK study identifier: HO-14-14319.  相似文献   

90.
BACKGROUND: Intradermal botolinum toxin A (BTXA) is an advanced technique that emerged in response to the increased demand for noninvasive facial lifting and skin rejuvenation. OBJECTIVE: We sought to evaluate the safety and efficacy of intradermal injections of BTXA for facial lifting. METHODS: Twenty-five female patients with mild symmetrical facial skin laxity were enrolled in this study. All patients were treated with BTXA in one side of the face while the other side was injected with normal saline. The response to treatment was assessed by two dermatologists who evaluated global photographs using a quartile grading scale (QGS). The patient self-assessment and satisfaction questionnaires were recorded. RESULTS: A highly significant difference was found between the side injected with BTXA and the saline injected side (control) (p<0.001). Facial lifting was achieved in 58.66 percent of the sides injected with BTXA. Forty-four percent of patients were very satisfied. Older patients showed better improvement than younger patients (p=<0.001). The results persisted for 16 weeks. No adverse effects were observed. CONCLUSION: Our results suggest that intradermal injection of BTXA could be a safe and effective therapeutic option for face lifting.  相似文献   
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