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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38864574

RESUMO

The amygdala is present in a diverse range of vertebrate species, such as lizards, rodents, and primates; however, its structure and connectivity differs across species. The increased connections to visual sensory areas in primate species suggests that understanding the visual selectivity of the amygdala in detail is critical to revealing the principles underlying its function in primate cognition. Therefore, we designed a high-resolution, contrast-agent enhanced, event-related fMRI experiment, and scanned 3 adult rhesus macaques, while they viewed 96 naturalistic stimuli. Half of these stimuli were social (defined by the presence of a conspecific), the other half were nonsocial. We also nested manipulations of emotional valence (positive, neutral, and negative) and visual category (faces, nonfaces, animate, and inanimate) within the stimulus set. The results reveal widespread effects of emotional valence, with the amygdala responding more on average to inanimate objects and animals than faces, bodies, or social agents in this experimental context. These findings suggest that the amygdala makes a contribution to primate vision that goes beyond an auxiliary role in face or social perception. Furthermore, the results highlight the importance of stimulus selection and experimental design when probing the function of the amygdala and other visually responsive brain regions.


Assuntos
Tonsila do Cerebelo , Macaca mulatta , Imageamento por Ressonância Magnética , Estimulação Luminosa , Animais , Tonsila do Cerebelo/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Masculino , Estimulação Luminosa/métodos , Emoções/fisiologia , Mapeamento Encefálico , Percepção Visual/fisiologia , Feminino , Reconhecimento Visual de Modelos/fisiologia
2.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35074880

RESUMO

Despite our fluency in reading human faces, sometimes we mistakenly perceive illusory faces in objects, a phenomenon known as face pareidolia. Although illusory faces share some neural mechanisms with real faces, it is unknown to what degree pareidolia engages higher-level social perception beyond the detection of a face. In a series of large-scale behavioral experiments (ntotal = 3,815 adults), we found that illusory faces in inanimate objects are readily perceived to have a specific emotional expression, age, and gender. Most strikingly, we observed a strong bias to perceive illusory faces as male rather than female. This male bias could not be explained by preexisting semantic or visual gender associations with the objects, or by visual features in the images. Rather, this robust bias in the perception of gender for illusory faces reveals a cognitive bias arising from a broadly tuned face evaluation system in which minimally viable face percepts are more likely to be perceived as male.


Assuntos
Face/fisiologia , Ilusões/fisiologia , Adulto , Reconhecimento Facial/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos
3.
J Cogn Neurosci ; : 1-12, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38820560

RESUMO

The two cortical visual pathways framework has had a profound influence on theories and empirical studies of the visual system for over 40 years. By grounding physiological responses and behavior in neuroanatomy, the framework provided a critical guide for understanding vision. Although the framework has evolved over time, as our understanding of the physiology and neuroanatomy expanded, cortical visual processing is still often conceptualized as two separate pathways emerging from the primary visual cortex that support distinct behaviors ("what" vs. "where/how"). Here, we take a historical perspective and review the continuing evolution of the framework, discussing key and often overlooked insights. Rather than a functional and neuroanatomical bifurcation into two independent serial, hierarchical pathways, the current evidence points to two highly recurrent heterarchies with heterogeneous connections to cortical regions and subcortical structures that flexibly support a wide variety of behaviors. Although many of the simplifying assumptions of the framework are belied by the evidence gathered since its initial proposal, the core insight of grounding function and behavior in neuroanatomy remains fundamental. Given this perspective, we highlight critical open questions and the need for a better understanding of neuroanatomy, particularly in the human.

4.
Air Med J ; 43(3): 236-240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38821705

RESUMO

OBJECTIVE: This study aimed to describe the type and frequency of enteral and parenteral fluids and medications used during the transport of neonates by a regional pediatric critical care transport team. METHODS: We performed a retrospective analysis of neonates transported by a regional neonatal transport team affiliated with a level IV neonatal intensive care unit within a large care network between 2020 and 2021. Demographic and clinical data were collected from the electronic medical record. Standard frequency tabulation and summary statistics were used to report demographics, transport characteristics, and fluid and medication use; results were then stratified by preterm (37 weeks) and term births. RESULTS: In the 628 included transports, more term than preterm infants received at least 1 fluid or medication (53% vs. 43%, respectively). The most commonly administered medications were antibiotics (ampicillin and gentamicin), prostaglandin, and opiates (morphine sulfate and fentanyl). In addition, term infants received more analgesic medications, antimicrobials, and prostaglandin, whereas preterm infants received total parenteral nutrition more often. There were over 38 different medications provided on the transports studied. CONCLUSION: This study of a single transport team revealed that a wide variety of medications and fluids were used in the transport of neonates, with term infants receiving more medications than preterm infants. These data could be used by transport teams in making or updating their standardized medication lists or in creating simulations.


Assuntos
Transporte de Pacientes , Humanos , Recém-Nascido , Estudos Retrospectivos , Feminino , Masculino , Cuidados Críticos , Unidades de Terapia Intensiva Neonatal , Recém-Nascido Prematuro , Resgate Aéreo , Hidratação/métodos , Antibacterianos/uso terapêutico
5.
J Neurosci ; 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35868861

RESUMO

According to a prominent view in neuroscience, visual stimuli are coded by discrete cortical networks that respond preferentially to specific categories, such as faces or objects. However, it remains unclear how these category-selective networks respond when viewing conditions are cluttered, i.e., when there is more than one stimulus in the visual field. Here, we asked three questions: (1) Does clutter reduce the response and selectivity for faces as a function of retinal location? (2) Is the preferential response to faces uniform across the visual field? And (3) Does the ventral visual pathway encode information about the location of cluttered faces? We used fMRI to measure the response of the face-selective network in awake, fixating macaques (2 female, 5 male). Across a series of four experiments, we manipulated the presence and absence of clutter, as well as the location of the faces relative to the fovea. We found that clutter reduces the response to peripheral faces. When presented in isolation, without clutter, the selectivity for faces is fairly uniform across the visual field, but, when clutter is present, there is a marked decrease in the selectivity for peripheral faces. We also found no evidence of a contralateral visual field bias when faces were presented in clutter. Nonetheless, multivariate analyses revealed that the location of cluttered faces could be decoded from the multivoxel response of the face-selective network. Collectively, these findings demonstrate that clutter blunts the selectivity of the face-selective network to peripheral faces, although information about their retinal location is retained.SIGNIFICANCE STATEMENTNumerous studies that have measured brain activity in macaques have found visual regions that respond preferentially to faces. Although these regions are thought to be essential for social behavior, their responses have typically been measured while faces were presented in isolation, a situation atypical of the real world. How do these regions respond when faces are presented with other stimuli? We report that, when clutter is present, the preferential response to foveated faces is spared but preferential response to peripheral faces is reduced. Our results indicate that the presence of clutter changes the response of the face-selective network.

6.
J Neurosci ; 41(11): 2382-2392, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33500275

RESUMO

The initial encoding of visual information primarily from the contralateral visual field is a fundamental organizing principle of the primate visual system. Recently, the presence of such retinotopic sensitivity has been shown to extend well beyond early visual cortex to regions not historically considered retinotopically sensitive. In particular, human scene-selective regions in parahippocampal and medial parietal cortex exhibit prominent biases for the contralateral visual field. Here, we used fMRI to test the hypothesis that the human hippocampus, which is thought to be anatomically connected with these scene-selective regions, would also exhibit a biased representation of contralateral visual space. First, population receptive field (pRF) mapping with scene stimuli revealed strong biases for the contralateral visual field in bilateral hippocampus. Second, the distribution of retinotopic sensitivity suggested a more prominent representation in anterior medial portions of the hippocampus. Finally, the contralateral bias was confirmed in independent data taken from the Human Connectome Project (HCP) initiative. The presence of contralateral biases in the hippocampus, a structure considered by many as the apex of the visual hierarchy, highlights the truly pervasive influence of retinotopy. Moreover, this finding has important implications for understanding how visual information relates to the allocentric global spatial representations known to be encoded therein.SIGNIFICANCE STATEMENT Retinotopic encoding of visual information is an organizing principle of visual cortex. Recent work demonstrates this sensitivity in structures far beyond early visual cortex, including those anatomically connected to the hippocampus. Here, using population receptive field (pRF) modeling in two independent sets of data we demonstrate a consistent bias for the contralateral visual field in bilateral hippocampus. Such a bias highlights the truly pervasive influence of retinotopy, with important implications for understanding how the presence of retinotopy relates to more allocentric spatial representations.


Assuntos
Hipocampo/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico/métodos , Conectoma , Feminino , Lateralidade Funcional , Corpos Geniculados/fisiologia , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Giro Para-Hipocampal/fisiologia , Estimulação Luminosa , Retina/fisiologia , Campos Visuais , Adulto Jovem
7.
J Neurosci ; 41(13): 2980-2989, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33563728

RESUMO

The idea that when we use a tool we incorporate it into the neural representation of our body (embodiment) has been a major inspiration for philosophy, science, and engineering. While theoretically appealing, there is little direct evidence for tool embodiment at the neural level. Using functional magnetic resonance imaging (fMRI) in male and female human subjects, we investigated whether expert tool users (London litter pickers: n = 7) represent their expert tool more like a hand (neural embodiment) or less like a hand (neural differentiation), as compared with a group of tool novices (n = 12). During fMRI scans, participants viewed first-person videos depicting grasps performed by either a hand, litter picker, or a non-expert grasping tool. Using representational similarity analysis (RSA), differences in the representational structure of hands and tools were measured within occipitotemporal cortex (OTC). Contrary to the neural embodiment theory, we find that the experts group represent their own tool less like a hand (not more) relative to novices. Using a case-study approach, we further replicated this effect, independently, in five of the seven individual expert litter pickers, as compared with the novices. An exploratory analysis in left parietal cortex, a region implicated in visuomotor representations of hands and tools, also indicated that experts do not visually represent their tool more similar to hands, compared with novices. Together, our findings suggest that extensive tool use leads to an increased neural differentiation between visual representations of hands and tools. This evidence provides an important alternative framework to the prominent tool embodiment theory.SIGNIFICANCE STATEMENT It is commonly thought that tool use leads to the assimilation of the tool into the neural representation of the body, a process referred to as embodiment. Here, we demonstrate that expert tool users (London litter pickers) neurally represent their own tool less like a hand (not more), compared with novices. Our findings advance our current understanding for how experience shapes functional organization in high-order visual cortex. Further, this evidence provides an alternative framework to the prominent tool embodiment theory, suggesting instead that experience with tools leads to more distinct, separable hand and tool representations.


Assuntos
Encéfalo/fisiologia , Mãos/fisiologia , Imageamento por Ressonância Magnética/métodos , Destreza Motora/fisiologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Neurosci ; 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099511

RESUMO

The map of category-selectivity in human ventral temporal cortex (VTC) provides organizational constraints to models of object recognition. One important principle is lateral-medial response biases to stimuli that are typically viewed in the center or periphery of the visual field. However, little is known about the relative temporal dynamics and location of regions that respond preferentially to stimulus classes that are centrally viewed, like the face- and word-processing networks. Here, word- and face-selective regions within VTC were mapped using intracranial recordings from 36 patients. Partially overlapping, but also anatomically dissociable patches of face- and word-selectivity were found in VTC. In addition to canonical word-selective regions along the left posterior occipitotemporal sulcus, selectivity was also located medial and anterior to face-selective regions on the fusiform gyrus at the group level and within individual male and female subjects. These regions were replicated using 7 Tesla fMRI in healthy subjects. Left hemisphere word-selective regions preceded right hemisphere responses by 125 ms, potentially reflecting the left hemisphere bias for language; with no hemispheric difference in face-selective response latency. Word-selective regions along the posterior fusiform responded first, then spread medially and laterally, then anteriorally. Face-selective responses were first seen in posterior fusiform regions bilaterally, then proceeded anteriorally from there. For both words and faces, the relative delay between regions was longer than would be predicted by purely feedforward models of visual processing. The distinct time-courses of responses across these regions, and between hemispheres, suggest a complex and dynamic functional circuit supports face and word perception.SIGNIFICANCE STATEMENT:Representations of visual objects in the human brain have been shown to be organized by several principles, including whether those objects tend to be viewed centrally or peripherally in the visual field. However, it remains unclear how regions that process objects that are viewed centrally, like words and faces, are organized relative to one another. Here, invasive and non-invasive neuroimaging suggests there is a mosaic of regions in ventral temporal cortex that respond selectively to either words or faces. These regions display differences in the strength and timing of their responses, both within and between brain hemispheres, suggesting they play different roles in perception. These results illuminate extended, bilateral, and dynamic brain pathways that support face perception and reading.

9.
Nat Rev Neurosci ; 18(2): 115-126, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28053326

RESUMO

Functional neuroimaging techniques have transformed our ability to probe the neurobiological basis of behaviour and are increasingly being applied by the wider neuroscience community. However, concerns have recently been raised that the conclusions that are drawn from some human neuroimaging studies are either spurious or not generalizable. Problems such as low statistical power, flexibility in data analysis, software errors and a lack of direct replication apply to many fields, but perhaps particularly to functional MRI. Here, we discuss these problems, outline current and suggested best practices, and describe how we think the field should evolve to produce the most meaningful and reliable answers to neuroscientific questions.


Assuntos
Neuroimagem Funcional/normas , Imageamento por Ressonância Magnética/normas , Neuroimagem Funcional/estatística & dados numéricos , Neuroimagem Funcional/tendências , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Imageamento por Ressonância Magnética/tendências , Guias de Prática Clínica como Assunto/normas , Reprodutibilidade dos Testes , Software/normas , Estatística como Assunto
10.
Artigo em Inglês | MEDLINE | ID: mdl-35609964

RESUMO

Phantom limb pain (PLP) impacts the majority of individuals who undergo limb amputation. The PLP experience is highly heterogenous in its quality, intensity, frequency and severity. This heterogeneity, combined with the low prevalence of amputation in the general population, has made it difficult to accumulate reliable data on PLP. Consequently, we lack consensus on PLP mechanisms, as well as effective treatment options. However, the wealth of new PLP research, over the past decade, provides a unique opportunity to re-evaluate some of the core assumptions underlying what we know about PLP and the rationale behind PLP treatments. The goal of this review is to help generate consensus in the field on how best to research PLP, from phenomenology to treatment. We highlight conceptual and methodological challenges in studying PLP, which have hindered progress on the topic and spawned disagreement in the field, and offer potential solutions to overcome these challenges. Our hope is that a constructive evaluation of the foundational knowledge underlying PLP research practices will enable more informed decisions when testing the efficacy of existing interventions and will guide the development of the next generation of PLP treatments.

11.
AJR Am J Roentgenol ; 219(6): 895-902, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35822644

RESUMO

BACKGROUND. Artificial intelligence (AI) algorithms have shown strong performance for detection of pulmonary embolism (PE) on CT examinations performed using a dedicated protocol for PE detection. AI performance is less well studied for detecting PE on examinations ordered for reasons other than suspected PE (i.e., incidental PE [iPE]). OBJECTIVE. The purpose of this study was to assess the diagnostic performance of an AI algorithm for detection of iPE on conventional contrast-enhanced chest CT examinations. METHODS. This retrospective study included 2555 patients (mean age, 53.2 ± 14.5 [SD] years; 1340 women, 1215 men) who underwent 3003 conventional contrast-enhanced chest CT examinations (i.e., not using pulmonary CTA protocols) between September 2019 and February 2020. A commercial AI algorithm was applied to the images to detect acute iPE. A vendor-supplied natural language processing (NLP) algorithm was applied to the clinical reports to identify examinations interpreted as positive for iPE. For all examinations that were positive by the AI-based image review or by NLP-based report review, a multireader adjudication process was implemented to establish a reference standard for iPE. Images were also reviewed to identify explanations of AI misclassifications. RESULTS. On the basis of the adjudication process, the frequency of iPE was 1.3% (40/3003). AI detected four iPEs missed by clinical reports, and clinical reports detected seven iPEs missed by AI. AI, compared with clinical reports, exhibited significantly lower PPV (86.8% vs 97.3%, p = .03) and specificity (99.8% vs 100.0%, p = .045). Differences in sensitivity (82.5% vs 90.0%, p = .37) and NPV (99.8% vs 99.9%, p = .36) were not significant. For AI, neither sensitivity nor specificity varied significantly in association with age, sex, patient status, or cancer-related clinical scenario (all p > .05). Explanations of false-positives by AI included metastatic lymph nodes and pulmonary venous filling defect, and explanations of false-negatives by AI included surgically altered anatomy and small-caliber subsegmental vessels. CONCLUSION. AI had high NPV and moderate PPV for iPE detection, detecting some iPEs missed by radiologists. CLINICAL IMPACT. Potential applications of the AI tool include serving as a second reader to help detect additional iPEs or as a worklist triage tool to allow earlier iPE detection and intervention. Various explanations of AI misclassifications may provide targets for model improvement.


Assuntos
Inteligência Artificial , Embolia Pulmonar , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/complicações , Tomografia Computadorizada por Raios X/métodos , Tórax
12.
Cereb Cortex ; 31(4): 1898-1913, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33285563

RESUMO

During memory recall and visual imagery, reinstatement is thought to occur as an echoing of the neural patterns during encoding. However, the precise information in these recall traces is relatively unknown, with previous work primarily investigating either broad distinctions or specific images, rarely bridging these levels of information. Using ultra-high-field (7T) functional magnetic resonance imaging with an item-based visual recall task, we conducted an in-depth comparison of encoding and recall along a spectrum of granularity, from coarse (scenes, objects) to mid (e.g., natural, manmade scenes) to fine (e.g., living room, cupcake) levels. In the scanner, participants viewed a trial-unique item, and after a distractor task, visually imagined the initial item. During encoding, we observed decodable information at all levels of granularity in category-selective visual cortex. In contrast, information during recall was primarily at the coarse level with fine-level information in some areas; there was no evidence of mid-level information. A closer look revealed segregation between voxels showing the strongest effects during encoding and those during recall, and peaks of encoding-recall similarity extended anterior to category-selective cortex. Collectively, these results suggest visual recall is not merely a reactivation of encoding patterns, displaying a different representational structure and localization from encoding, despite some overlap.


Assuntos
Imaginação/fisiologia , Imageamento por Ressonância Magnética/métodos , Rememoração Mental/fisiologia , Estimulação Luminosa/métodos , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
13.
Memory ; 30(3): 279-292, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34913412

RESUMO

Drawings of scenes made from memory can be highly detailed and spatially accurate, with little information not found in the observed stimuli. While prior work has focused on studying memory for distinct scenes, less is known about the specific detail recalled when episodes are highly similar and competing. Here, participants (N = 30) were asked to study and recall eight complex scene images using a drawing task. Importantly, four of these images were exemplars of different scene categories, while the other four images were from the same scene category. The resulting 213 drawings were judged by 1764 online scorers for a comprehensive set of measures, including scene and object diagnosticity, spatial information, and fixation and pen movement behaviour. We observed that competition in memory resulted in diminished object detail, with drawings and objects that were less diagnostic of their original image. However, repeated exemplars of a category did not result in differences in spatial memory accuracy, and there were no differences in fixations during study or pen movements during recall. These results reveal that while drawings for distinct categories of scenes can be highly detailed and accurate, drawings for scenes from repeated categories, creating competition in memory, show reduced object detail.


Assuntos
Rememoração Mental , Memória Espacial , Humanos , Reconhecimento Visual de Modelos
14.
J Digit Imaging ; 35(1): 21-28, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34997374

RESUMO

In this article, we demonstrate the use of a software-based radiologist reporting tool for the implementation of American College of Radiology Thyroid Imaging, Reporting and Data System thyroid nodule risk-stratification. The technical details are described with emphasis on addressing the information security and patient privacy issues while allowing it to integrate with the electronic health record and radiology reporting dictation software. Its practical implementation is assessed in a quality improvement project in which guideline adherence and recommendation congruence were measured pre and post implementation. The descriptions of our solution and the release of the open-sourced codes may be helpful in future implementation of similar web-based calculators.


Assuntos
Nódulo da Glândula Tireoide , Humanos , Internet , Estudos Retrospectivos , Software , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos
15.
Neuroimage ; 230: 117790, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497776

RESUMO

Human visual cortex contains three scene-selective regions in the lateral, medial and ventral cortex, termed the occipital place area (OPA), medial place area (MPA) and parahippocampal place area (PPA). Using functional magnetic resonance imaging (fMRI), all three regions respond more strongly when viewing visual scenes compared with isolated objects or faces. To determine how these regions are functionally and causally connected, we applied transcranial magnetic stimulation to OPA and measured fMRI responses before and after stimulation, using a theta-burst paradigm (TBS). To test for stimulus category-selectivity, we presented a range of visual categories (scenes, buildings, objects, faces). To test for specificity of any effects to TBS of OPA we employed two control conditions: Sham, with no TBS stimulation, and an active TBS-control with TBS to a proximal face-selective cortical region (occipital face area, or OFA). We predicted that TBS to OPA (but not OFA) would lead to decreased responses to scenes and buildings (but not other categories) in other scene-selective cortical regions. Across both ROI and whole-volume analyses, we observed decreased responses to scenes in PPA as a result of TBS. However, these effects were neither category specific, with decreased responses to all stimulus categories, nor limited to scene-selective regions, with decreases also observed in face-selective fusiform face area (FFA). Furthermore, similar effects were observed with TBS to OFA, thus effects were not specific to the stimulation site in the lateral occipital cortex. Whilst these data are suggestive of a causal, but non-specific relationship between lateral occipital and ventral temporal cortex, we discuss several factors that could have underpinned this result, such as the differences between TBS and online TMS, the role of anatomical distance between stimulated regions and how TMS effects are operationalised. Furthermore, our findings highlight the importance of active control conditions in brain stimulation experiments to accurately assess functional and causal connectivity between specific brain regions.


Assuntos
Lobo Occipital/metabolismo , Consumo de Oxigênio/fisiologia , Estimulação Luminosa/métodos , Lobo Temporal/metabolismo , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Lobo Occipital/diagnóstico por imagem , Tempo de Reação/fisiologia , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
16.
Cereb Cortex ; 30(2): 778-785, 2020 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-31264693

RESUMO

Neuroimaging studies show that ventral face-selective regions, including the fusiform face area (FFA) and occipital face area (OFA), preferentially respond to faces presented in the contralateral visual field (VF). In the current study we measured the VF response of the face-selective posterior superior temporal sulcus (pSTS). Across 3 functional magnetic resonance imaging experiments, participants viewed face videos presented in different parts of the VF. Consistent with prior results, we observed a contralateral VF bias in bilateral FFA, right OFA (rOFA), and bilateral human motion-selective area MT+. Intriguingly, this contralateral VF bias was absent in the bilateral pSTS. We then delivered transcranial magnetic stimulation (TMS) over right pSTS (rpSTS) and rOFA, while participants matched facial expressions in both hemifields. TMS delivered over the rpSTS disrupted performance in both hemifields, but TMS delivered over the rOFA disrupted performance in the contralateral hemifield only. These converging results demonstrate that the contralateral bias for faces observed in ventral face-selective areas is absent in the pSTS. This difference in VF response is consistent with face processing models proposing 2 functionally distinct pathways. It further suggests that these models should account for differences in interhemispheric connections between the face-selective areas across these 2 pathways.


Assuntos
Reconhecimento Facial/fisiologia , Lobo Temporal/fisiologia , Mapeamento Encefálico , Expressão Facial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Magnética Transcraniana , Campos Visuais
17.
Mem Cognit ; 49(8): 1568-1582, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34031795

RESUMO

Humans are highly sensitive to the statistical relationships between features and objects within visual scenes. Inconsistent objects within scenes (e.g., a mailbox in a bedroom) instantly jump out to us and are known to catch our attention. However, it is debated whether such semantic inconsistencies result in boosted memory for the scene, impaired memory, or have no influence on memory. Here, we examined the relationship of scene-object consistencies on memory representations measured through drawings made during recall. Participants (N = 30) were eye-tracked while studying 12 real-world scene images with an added object that was either semantically consistent or inconsistent. After a 6-minute distractor task, they drew the scenes from memory while pen movements were tracked electronically. Online scorers (N = 1,725) rated each drawing for diagnosticity, object detail, spatial detail, and memory errors. Inconsistent scenes were recalled more frequently, but contained less object detail. Further, inconsistent objects elicited more errors reflecting looser memory binding (e.g., migration across images). These results point to a dual effect in memory of boosted global (scene) but diminished local (object) information. Finally, we observed that participants fixate longest on inconsistent objects, but these fixations during study were not correlated with recall performance, time, or drawing order. In sum, these results show a nuanced effect of scene inconsistencies on memory detail during recall.


Assuntos
Reconhecimento Visual de Modelos , Semântica , Atenção , Humanos , Rememoração Mental , Percepção Visual
18.
J Drugs Dermatol ; 20(10): 1063-1071, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34636525

RESUMO

While biological treatments for chronic plaque psoriasis should be administered continuously to maximize and maintain efficacy, interruptions in therapy may be necessary for a number of reasons. We reviewed the evidence from clinical trials on efficacy, safety and immunogenicity in clinical trials for approved biologic agents for chronic plaque psoriasis. A systematic search of three major medical databases was performed and a total of 35 articles were included into the analysis, including 13 controlled trials. Trials assessing continuous therapy against dosing as-needed therapy (including infliximab, etanercept and secukinumab) have demonstrated superior efficacy for continuous regimes. However, randomized withdrawal trials for etanercept, adalimumab, ixekizumab, brodalumab, guselkumab, risankizumab and tildrakizumab, showed no significant impact on skin clearance rates in patients who are interrupted once and then re-treated. With the possible exception of infliximab, temporary interruption in biologic therapy appears to be safe and most agents will regain efficacy after re-introduction. J Drugs Dermatol. 2021;20(10):1063-1071. doi:10.36849/JDD.5716.


Assuntos
Psoríase , Adalimumab/efeitos adversos , Terapia Biológica , Etanercepte/efeitos adversos , Humanos , Infliximab , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Resultado do Tratamento
19.
J Gerontol Nurs ; 47(10): 37-43, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34590973

RESUMO

Hospital inpatient falls, especially of older adult patients, can result in injury and death and generate high costs. A new technology, PUP® (Patient Is Up) Smart Socks, combines sensors and geolocation in socks with a wireless platform. To determine whether these socks prevent falls of patients with high fall risk, we performed a clinical trial at one hospital, and an observational study at two other hospitals. In the clinical trial, patients spent 1,694 patient-days wearing the socks, reducing falls from 4 to 0 per 1,000 patient-days (p < 0.01). In the observational study, patients spent 2,286 patient-days wearing the socks, reducing falls from 4 to 1.3 per 1,000 patient-days (p < 0.05). The new technology resulted in a significant reduction in fall rates among patients with high fall risk and may greatly reduce inpatient fall-related injury and death and their associated costs. [Journal of Gerontological Nursing, 47(10), 37-43.].


Assuntos
Acidentes por Quedas , Pacientes Internados , Acidentes por Quedas/prevenção & controle , Idoso , Hospitais , Humanos , Tecnologia
20.
J Neurosci ; 39(4): 705-717, 2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30504281

RESUMO

Human retrosplenial complex (RSC), located in medial parietal cortex, has been implicated in numerous cognitive functions, including scene perception, spatial navigation, and autobiographical memory retrieval. Recently, a posterior-anterior distinction within RSC was proposed, such that posterior aspects process scene-related visual information (constituting a medial place area [MPA]), whereas anterior aspects process information that is vividly retrieved from memory, thereby supporting remembering and potentially navigation. Here, we tested this proposed distinction in a single group of participants (both male and female) using fMRI with both perceptual and mnemonic tasks. After completing a resting-state scan, participants performed a task that required constructing scenes from memory and completed a scene selectivity localizer task. We tested directly perceptual and mnemonic responses in MPA and an anterior, connectivity-defined region (CON), which showed strong functional connectivity with anterior parahippocampal place area. A double dissociation was observed, such that CON was more strongly activated during scene construction than was MPA, whereas MPA was more perceptually responsive than CON. Further, peak responses from the scene construction task were anterior to perceptual peaks in all but 1 participant and hemisphere. Finally, through analyses of the posterior-anterior response profiles, we identify the fundus of the parieto-occipital sulcus as a potential location for the crossover from perceptual to mnemonic representations and highlight a potential left-hemisphere advantage for mnemonic representations. Collectively, our results support a distinction between posterior and anterior aspects of the RSC, suggesting that more specific functional-anatomic terms should be used in its place in future work.SIGNIFICANCE STATEMENT The retrosplenial complex (RSC) has been implicated in vision, spatial cognition, and memory. We previously speculated on a potential posterior-anterior distinction within RSC for scene perception and memory-based scene construction/navigation. Here, we tested this distinction through a combination of resting-state, perceptual, and mnemonic task data. Consistent with our predictions, we demonstrate that perceptual responses peak consistently posterior of those elicited by memory-based scene construction within the broader RSC. Further, we highlight (1) the fundus of the parieto-occipital sulcus as a landmark for the transition between these representations, (2) the anterior bank of parieto-occipital sulcus as the point of maximal separation between these representations, and (3) identify a potential hemispheric asymmetry in mnemonic representations. These data support functional dissociations within RSC.


Assuntos
Memória/fisiologia , Lobo Parietal/fisiologia , Percepção Espacial/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Lobo Occipital/fisiologia , Giro Para-Hipocampal/fisiologia , Lobo Parietal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Adulto Jovem
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