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1.
Neurobiol Sleep Circadian Rhythms ; 16: 100103, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38585223

RESUMO

Day length, or photoperiod, is a reliable environmental cue encoded by the brain's circadian clock that indicates changing seasons and induces seasonal biological processes. In humans, photoperiod, age, and sex have been linked to seasonality in neuropsychiatric disorders, as seen in Seasonal Affective Disorder, Major Depressive Disorder, and Bipolar Disorder. The nucleus accumbens is a key locus for the regulation of motivated behaviors and neuropsychiatric disorders. Using periadolescent and young adult male and female mice, here we assessed photoperiod's effect on serotonin and dopamine tissue content in the nucleus accumbens core, as well as on accumbal synaptic dopamine release and uptake. We found greater serotonin and dopamine tissue content in the nucleus accumbens from young adult mice raised in a Short winter-like photoperiod. In addition, dopamine release and clearance were greater in the nucleus accumbens from young adult mice raised in a Long summer-like photoperiod. Importantly, we found that photoperiod's effects on accumbal dopamine tissue content and release were sex-specific to young adult females. These findings support that in mice there are interactions across age, sex, and photoperiod that impact critical monoamine neuromodulators in the nucleus accumbens which may provide mechanistic insight into the age and sex dependencies in seasonality of neuropsychiatric disorders in humans.

2.
Trials ; 25(1): 66, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243291

RESUMO

BACKGROUND: Robotic-assisted bronchoscopy has recently emerged as an alternative to electromagnetic navigational bronchoscopy for the evaluation of peripheral pulmonary lesions. While robotic-assisted bronchoscopy is proposed to have several advantages, such as an easier learning curve, it is unclear if it has comparable diagnostic utility as electromagnetic navigational bronchoscopy. METHODS: Robotic versus Electromagnetic bronchoscopy for pulmonary LesIon AssessmeNT (RELIANT) is an investigator-initiated, single-center, open label, noninferiority, cluster randomized controlled trial conducted in two operating rooms at Vanderbilt University Medical Center. Each operating room (OR) is assigned to either robotic-assisted or electromagnetic navigational bronchoscopy each morning, with each OR day considered one cluster. All patients undergoing diagnostic bronchoscopy for evaluation of a peripheral pulmonary lesion in one of the two operating rooms are eligible. Schedulers, patients, and proceduralists are blinded to daily group allocations until randomization is revealed for each operating room each morning. The primary endpoint is the diagnostic yield defined as the proportion of cases yielding lesional tissue. Secondary and safety endpoints include procedure duration and procedural complications. Enrolment began on March 6, 2023, and will continue until 202 clusters have been accrued, with expected enrolment of approximately 400 patients by the time of completion in March of 2024. DISCUSSION: RELIANT is a pragmatic randomized controlled trial that will compare the diagnostic yield of the two most commonly used bronchoscopic approaches for sampling peripheral pulmonary lesions. This will be the first known cluster randomized pragmatic trial in the interventional pulmonology field and the first randomized controlled trial of robotic-assisted bronchoscopy. TRIAL REGISTRATION: ClinicalTrials.gov registration (NCT05705544) on January 30, 2023.


Assuntos
Neoplasias Pulmonares , Procedimentos Cirúrgicos Robóticos , Humanos , Broncoscopia/efeitos adversos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Pulmão/patologia , Fenômenos Eletromagnéticos
3.
Genome Biol Evol ; 15(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095367

RESUMO

When the ancestors of modern Eurasians migrated out of Africa and interbred with Eurasian archaic hominins, namely, Neanderthals and Denisovans, DNA of archaic ancestry integrated into the genomes of anatomically modern humans. This process potentially accelerated adaptation to Eurasian environmental factors, including reduced ultraviolet radiation and increased variation in seasonal dynamics. However, whether these groups differed substantially in circadian biology and whether archaic introgression adaptively contributed to human chronotypes remain unknown. Here, we traced the evolution of chronotype based on genomes from archaic hominins and present-day humans. First, we inferred differences in circadian gene sequences, splicing, and regulation between archaic hominins and modern humans. We identified 28 circadian genes containing variants with potential to alter splicing in archaics (e.g., CLOCK, PER2, RORB, and RORC) and 16 circadian genes likely divergently regulated between present-day humans and archaic hominins, including RORA. These differences suggest the potential for introgression to modify circadian gene expression. Testing this hypothesis, we found that introgressed variants are enriched among expression quantitative trait loci for circadian genes. Supporting the functional relevance of these regulatory effects, we found that many introgressed alleles have associations with chronotype. Strikingly, the strongest introgressed effects on chronotype increase morningness, consistent with adaptations to high latitude in other species. Finally, we identified several circadian loci with evidence of adaptive introgression or latitudinal clines in allele frequency. These findings identify differences in circadian gene regulation between modern humans and archaic hominins and support the contribution of introgression via coordinated effects on variation in human chronotype.


Assuntos
Hominidae , Homem de Neandertal , Animais , Humanos , Raios Ultravioleta , Genoma Humano , Hominidae/genética , Homem de Neandertal/genética , Frequência do Gene
4.
JAMA ; 330(16): 1557-1567, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37837651

RESUMO

Importance: Cefepime and piperacillin-tazobactam are commonly administered to hospitalized adults for empirical treatment of infection. Although piperacillin-tazobactam has been hypothesized to cause acute kidney injury and cefepime has been hypothesized to cause neurological dysfunction, their comparative safety has not been evaluated in a randomized clinical trial. Objective: To determine whether the choice between cefepime and piperacillin-tazobactam affects the risks of acute kidney injury or neurological dysfunction. Design, Setting, and Participants: The Antibiotic Choice on Renal Outcomes (ACORN) randomized clinical trial compared cefepime vs piperacillin-tazobactam in adults for whom a clinician initiated an order for antipseudomonal antibiotics within 12 hours of presentation to the hospital in the emergency department or medical intensive care unit at an academic medical center in the US between November 10, 2021, and October 7, 2022. The final date of follow-up was November 4, 2022. Interventions: Patients were randomized in a 1:1 ratio to cefepime or piperacillin-tazobactam. Main Outcomes and Measures: The primary outcome was the highest stage of acute kidney injury or death by day 14, measured on a 5-level ordinal scale ranging from no acute kidney injury to death. The 2 secondary outcomes were the incidence of major adverse kidney events at day 14 and the number of days alive and free of delirium and coma within 14 days. Results: There were 2511 patients included in the primary analysis (median age, 58 years [IQR, 43-69 years]; 42.7% were female; 16.3% were Non-Hispanic Black; 5.4% were Hispanic; 94.7% were enrolled in the emergency department; and 77.2% were receiving vancomycin at enrollment). The highest stage of acute kidney injury or death was not significantly different between the cefepime group and the piperacillin-tazobactam group; there were 85 patients (n = 1214; 7.0%) in the cefepime group with stage 3 acute kidney injury and 92 (7.6%) who died vs 97 patients (n = 1297; 7.5%) in the piperacillin-tazobactam group with stage 3 acute kidney injury and 78 (6.0%) who died (odds ratio, 0.95 [95% CI, 0.80 to 1.13], P = .56). The incidence of major adverse kidney events at day 14 did not differ between groups (124 patients [10.2%] in the cefepime group vs 114 patients [8.8%] in the piperacillin-tazobactam group; absolute difference, 1.4% [95% CI, -1.0% to 3.8%]). Patients in the cefepime group experienced fewer days alive and free of delirium and coma within 14 days (mean [SD], 11.9 [4.6] days vs 12.2 [4.3] days in the piperacillin-tazobactam group; odds ratio, 0.79 [95% CI, 0.65 to 0.95]). Conclusions and Relevance: Among hospitalized adults in this randomized clinical trial, treatment with piperacillin-tazobactam did not increase the incidence of acute kidney injury or death. Treatment with cefepime resulted in more neurological dysfunction. Trial Registration: ClinicalTrials.gov Identifier: NCT05094154.


Assuntos
Injúria Renal Aguda , Delírio , Sepse , Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Masculino , Antibacterianos/efeitos adversos , Cefepima/efeitos adversos , Coma , Piperacilina/efeitos adversos , Quimioterapia Combinada , Estudos Retrospectivos , Combinação Piperacilina e Tazobactam/efeitos adversos , Sepse/complicações , Injúria Renal Aguda/etiologia , Rim
5.
Res Sq ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37693467

RESUMO

Background: Robotic assisted bronchoscopy has recently emerged as an alternative to electromagnetic navigational bronchoscopy for the evaluation of peripheral pulmonary lesions. While robotic assisted bronchoscopy is proposed to have several advantages, such as an easier learning curve, it is unclear if it has comparable diagnostic utility as electromagnetic navigational bronchoscopy. Methods: Robotic versus Electromagnetic Bronchoscopy for Pulmonary LesIon AssessmeNT (RELIANT) is an investigator-initiated, single-center, open label, noninferiority, cluster randomized controlled trial conducted in two operating rooms at Vanderbilt University Medical Center. Each operating room is assigned to either robotic assisted or electromagnetic navigational bronchoscopy each morning, with each OR day considered one cluster. All patients undergoing diagnostic bronchoscopy for evaluation of a peripheral pulmonary lesion in one of the two operating rooms are eligible. Schedulers, patients and proceduralists are blinded to daily group allocations until randomization is revealed for each operating room each morning. The primary endpoint is the diagnostic yield defined as the proportion of cases yielding lesional tissue. Secondary and safety endpoints include procedure duration and procedural complications. Enrolment began on March 6, 2023, and will continue until 202 clusters have been accrued, with expected enrolment of approximately 400 patients by the time of completion in March of 2024. Discussion: RELIANT is a pragmatic randomized controlled trial that will compare the diagnostic yield of the two most commonly used bronchoscopic approaches for sampling peripheral pulmonary lesions. This will be the first known cluster randomized pragmatic trial in the interventional pulmonology field and the first randomized controlled trial of robotic assisted bronchoscopy. Trial registration: ClinicalTrials.gov registration (NCT05705544) on January 30, 2023.

6.
eNeuro ; 10(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36781229

RESUMO

Circadian photoperiod, or day length, changes with the seasons and influences behavior to allow animals to adapt to their environment. Photoperiod is also associated with seasonal rhythms of affective state, as evidenced by seasonality of several neuropsychiatric disorders. Interestingly, seasonality tends to be more prevalent in women for affective disorders such as major depressive disorder and bipolar disorder (BD). However, the underlying neurobiological processes contributing to sex-linked seasonality of affective behaviors are largely unknown. Mesolimbic dopamine input to the nucleus accumbens (NAc) contributes to the regulation of affective state and behaviors. Additionally, sex differences in the mesolimbic dopamine pathway are well established. Therefore, we hypothesize that photoperiod may drive differential modulation of NAc dopamine in males and females. Here, we used fast-scan cyclic voltammetry (FSCV) to explore whether photoperiod can modulate subsecond dopamine signaling dynamics in the NAc core of male and female mice raised in seasonally relevant photoperiods. We found that photoperiod modulates dopamine signaling in the NAc core, and that this effect is sex-specific to females. Both release and uptake of dopamine were enhanced in the NAc core of female mice raised in long, summer-like photoperiods, whereas we did not find photoperiodic effects on NAc core dopamine in males. These findings uncover a potential neural circuit basis for sex-linked seasonality in affective behaviors.


Assuntos
Transtorno Depressivo Maior , Dopamina , Feminino , Ratos , Masculino , Camundongos , Animais , Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Ratos Sprague-Dawley , Fotoperíodo , Transtorno Depressivo Maior/metabolismo
7.
STAR Protoc ; 2(2): 100442, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33899023

RESUMO

Patch-clamp and multi-electrode array electrophysiology techniques are used to measure dynamic functional properties of neurons. Whole-cell and cell-attached patch-clamp recordings in brain slices can be performed in voltage-clamp and current-clamp configuration to reveal cell-type-specific synaptic and cellular parameters governing neurotransmission. Multi-electrode array electrophysiology can provide spike activity recordings from multiple neurons, enabling larger sample sizes, and long-term recordings. We provide our guide to preparing acute rodent brain slices with example experiments and analyses intended for novice and expert electrophysiologists. For complete details on the use and execution of this protocol, please refer to Manz et al. (2020b).


Assuntos
Encéfalo , Eletrofisiologia/métodos , Técnicas de Patch-Clamp/métodos , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios
8.
Neuroscience ; 457: 220-234, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33385488

RESUMO

Circadian disruptions, along with altered affective and reward states, are commonly associated with psychiatric disorders. In addition to genetics, the enduring influence of environmental factors in programming neural networks is of increased interest in assessing the underpinnings of mental health. The duration of daylight or photoperiod is known to impact both the serotonin and dopamine systems, which are implicated in mood and reward-based disorders. This review first examines the effects of circadian disruption and photoperiod in the serotonin system in both human and preclinical studies. We next highlight how brain regions crucial for the serotoninergic system (i.e., dorsal raphe nucleus; DRN), and dopaminergic (i.e., nucleus accumbens; NAc and ventral tegmental area; VTA) system are intertwined in overlapping circuitry, and play influential roles in the pathology of mood and reward-based disorders. We then focus on human and animal studies that demonstrate the impact of circadian factors on the dopaminergic system. Lastly, we discuss how environmental factors such as circadian photoperiod can impact the neural circuits that are responsible for regulating affective and reward states, offering novel insights into the biological mechanisms underlying the pathophysiology, systems, and therapeutic treatments necessary for mood and reward-based disorders.


Assuntos
Fotoperíodo , Recompensa , Animais , Núcleo Dorsal da Rafe , Humanos , Núcleo Accumbens , Área Tegmentar Ventral
9.
Autism Res ; 13(9): 1430-1449, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32869933

RESUMO

Abnormal sensory responses are a DSM-5 symptom of autism spectrum disorder (ASD), and research findings demonstrate altered sensory processing in ASD. Beyond difficulties with processing information within single sensory domains, including both hypersensitivity and hyposensitivity, difficulties in multisensory processing are becoming a core issue of focus in ASD. These difficulties may be targeted by treatment approaches such as "sensory integration," which is frequently applied in autism treatment but not yet based on clear evidence. Recently, psychophysical data have emerged to demonstrate multisensory deficits in some children with ASD. Unlike deficits in social communication, which are best understood in humans, sensory and multisensory changes offer a tractable marker of circuit dysfunction that is more easily translated into animal model systems to probe the underlying neurobiological mechanisms. Paralleling experimental paradigms that were previously applied in humans and larger mammals, we and others have demonstrated that multisensory function can also be examined behaviorally in rodents. Here, we review the sensory and multisensory difficulties commonly found in ASD, examining laboratory findings that relate these findings across species. Next, we discuss the known neurobiology of multisensory integration, drawing largely on experimental work in larger mammals, and extensions of these paradigms into rodents. Finally, we describe emerging investigations into multisensory processing in genetic mouse models related to autism risk. By detailing findings from humans to mice, we highlight the advantage of multisensory paradigms that can be easily translated across species, as well as the potential for rodent experimental systems to reveal opportunities for novel treatments. LAY SUMMARY: Sensory and multisensory deficits are commonly found in ASD and may result in cascading effects that impact social communication. By using similar experiments to those in humans, we discuss how studies in animal models may allow an understanding of the brain mechanisms that underlie difficulties in multisensory integration, with the ultimate goal of developing new treatments. Autism Res 2020, 13: 1430-1449. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Percepção , Animais , Transtorno do Espectro Autista/complicações , Cognição , Modelos Animais de Doenças , Humanos
10.
Sci Rep ; 10(1): 15437, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963273

RESUMO

Photoperiod or the duration of daylight has been implicated as a risk factor in the development of mood disorders. The dopamine and serotonin systems are impacted by photoperiod and are consistently associated with affective disorders. Hence, we evaluated, at multiple stages of postnatal development, the expression of key dopaminergic (TH) and serotonergic (Tph2, SERT, and Pet-1) genes, and midbrain monoamine content in mice raised under control Equinox (LD 12:12), Short winter-like (LD 8:16), or Long summer-like (LD 16:8) photoperiods. Focusing in early adulthood, we evaluated the midbrain levels of these serotonergic genes, and also assayed these gene levels in the dorsal raphe nucleus (DRN) with RNAScope. Mice that developed under Short photoperiods demonstrated elevated midbrain TH expression levels, specifically during perinatal development compared to mice raised under Long photoperiods, and significantly decreased serotonin and dopamine content throughout the course of development. In adulthood, Long photoperiod mice demonstrated decreased midbrain Tph2 and SERT expression levels and reduced Tph2 levels in the DRN compared Short photoperiod mice. Thus, evaluating gene × environment interactions in the dopaminergic and serotonergic systems during multiple stages of development may lead to novel insights into the underlying mechanisms in the development of affective disorders.


Assuntos
Monoaminas Biogênicas/metabolismo , Dopamina/metabolismo , Núcleo Dorsal da Rafe/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fotoperíodo , Serotonina/metabolismo , Animais , Núcleo Dorsal da Rafe/citologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Front Neurosci ; 13: 459, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31133791

RESUMO

Early life stimuli during critical developmental time frames have been linked to increased risk for neurodevelopmental disorders later in life. The serotonergic system of the brain is implicated in mood disorders and is impacted by the duration of daylight, or photoperiod. Here we sought to investigate sensitive periods of prenatal and postnatal development for photoperiodic programming of DRN serotonin neurons, midbrain serotonin and metabolite levels along with affective behaviors in adolescence (P30) or adulthood (P50). To address these questions we restricted the interval of exposure to prenatal development (E0-P0) for Long summer-like photoperiods (LD 16:8), or Short winter-like photoperiods (LD 8:16) with postnatal development and maturation then occurring under the opposing photoperiod. Prenatal exposure alone to Long photoperiods was sufficient to fully program increased excitability of DRN serotonin neurons into adolescence and adulthood, similar to maintained exposure to Long photoperiods throughout development. Interestingly, Long photoperiod exposure can elevate serotonin and its' corresponding metabolite levels along with reducing affective behavior, which appear to have both pre and postnatal origins. Thus, exposure to Long photoperiods prenatally programs increased DRN serotonin neuronal excitability, but this step is insufficient to program serotonin signaling and affective behavior. Continuing influence of Long photoperiods during postnatal development then modulates serotonergic content and has protective effects for depressive-like behavior. Photoperiodic programing of serotonin function in mice appears to be a sequential process with programing of neuronal excitability as a first step occurring prenatally, while programing of circuit level serotonin signaling and behavior extends into the postnatal period.

12.
J Autism Dev Disord ; 44(12): 3161-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25022248

RESUMO

Individuals with autism spectrum disorders (ASD) exhibit alterations in sensory processing, including changes in the integration of information across the different sensory modalities. In the current study, we used the sound-induced flash illusion to assess multisensory integration in children with ASD and typically-developing (TD) controls. Thirty-one children with ASD and 31 age and IQ matched TD children (average age = 12 years) were presented with simple visual (i.e., flash) and auditory (i.e., beep) stimuli of varying number. In illusory conditions, a single flash was presented with 2-4 beeps. In TD children, these conditions generally result in the perception of multiple flashes, implying a perceptual fusion across vision and audition. In the present study, children with ASD were significantly less likely to perceive the illusion relative to TD controls, suggesting that multisensory integration and cross-modal binding may be weaker in some children with ASD. These results are discussed in the context of previous findings for multisensory integration in ASD and future directions for research.


Assuntos
Estimulação Acústica/métodos , Percepção Auditiva/fisiologia , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/psicologia , Estimulação Luminosa/métodos , Percepção Visual/fisiologia , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Masculino
13.
Brain Topogr ; 27(6): 707-30, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24722880

RESUMO

We process information from the world through multiple senses, and the brain must decide what information belongs together and what information should be segregated. One challenge in studying such multisensory integration is how to quantify the multisensory interactions, a challenge that is amplified by the host of methods that are now used to measure neural, behavioral, and perceptual responses. Many of the measures that have been developed to quantify multisensory integration (and which have been derived from single unit analyses), have been applied to these different measures without much consideration for the nature of the process being studied. Here, we provide a review focused on the means with which experimenters quantify multisensory processes and integration across a range of commonly used experimental methodologies. We emphasize the most commonly employed measures, including single- and multiunit responses, local field potentials, functional magnetic resonance imaging, and electroencephalography, along with behavioral measures of detection, accuracy, and response times. In each section, we will discuss the different metrics commonly used to quantify multisensory interactions, including the rationale for their use, their advantages, and the drawbacks and caveats associated with them. Also discussed are possible alternatives to the most commonly used metrics.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Neurônios/fisiologia , Percepção/fisiologia , Animais , Interpretação Estatística de Dados , Eletroencefalografia/métodos , Humanos , Imageamento por Ressonância Magnética/métodos
14.
J Neurosci ; 34(3): 691-7, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24431427

RESUMO

The new DSM-5 diagnostic criteria for autism spectrum disorders (ASDs) include sensory disturbances in addition to the well-established language, communication, and social deficits. One sensory disturbance seen in ASD is an impaired ability to integrate multisensory information into a unified percept. This may arise from an underlying impairment in which individuals with ASD have difficulty perceiving the temporal relationship between cross-modal inputs, an important cue for multisensory integration. Such impairments in multisensory processing may cascade into higher-level deficits, impairing day-to-day functioning on tasks, such as speech perception. To investigate multisensory temporal processing deficits in ASD and their links to speech processing, the current study mapped performance on a number of multisensory temporal tasks (with both simple and complex stimuli) onto the ability of individuals with ASD to perceptually bind audiovisual speech signals. High-functioning children with ASD were compared with a group of typically developing children. Performance on the multisensory temporal tasks varied with stimulus complexity for both groups; less precise temporal processing was observed with increasing stimulus complexity. Notably, individuals with ASD showed a speech-specific deficit in multisensory temporal processing. Most importantly, the strength of perceptual binding of audiovisual speech observed in individuals with ASD was strongly related to their low-level multisensory temporal processing abilities. Collectively, the results represent the first to illustrate links between multisensory temporal function and speech processing in ASD, strongly suggesting that deficits in low-level sensory processing may cascade into higher-order domains, such as language and communication.


Assuntos
Estimulação Acústica/métodos , Percepção Auditiva/fisiologia , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adolescente , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/psicologia , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Fatores de Tempo
15.
J Autism Dev Disord ; 44(6): 1470-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24218241

RESUMO

Atypical communicative abilities are a core marker of Autism Spectrum Disorders (ASD). A number of studies have shown that, in addition to auditory comprehension differences, individuals with autism frequently show atypical responses to audiovisual speech, suggesting a multisensory contribution to these communicative differences from their typically developing peers. To shed light on possible differences in the maturation of audiovisual speech integration, we tested younger (ages 6-12) and older (ages 13-18) children with and without ASD on a task indexing such multisensory integration. To do this, we used the McGurk effect, in which the pairing of incongruent auditory and visual speech tokens typically results in the perception of a fused percept distinct from the auditory and visual signals, indicative of active integration of the two channels conveying speech information. Whereas little difference was seen in audiovisual speech processing (i.e., reports of McGurk fusion) between the younger ASD and TD groups, there was a significant difference at the older ages. While TD controls exhibited an increased rate of fusion (i.e., integration) with age, children with ASD failed to show this increase. These data suggest arrested development of audiovisual speech integration in ASD. The results are discussed in light of the extant literature and necessary next steps in research.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/psicologia , Percepção da Fala , Percepção Visual , Estimulação Acústica , Adolescente , Estudos de Casos e Controles , Criança , Compreensão , Feminino , Humanos , Masculino , Estimulação Luminosa
16.
Front Behav Neurosci ; 8: 456, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25628549

RESUMO

Human psychophysical and animal behavioral studies have illustrated the benefits that can be conferred from having information available from multiple senses. Given the central role of multisensory integration for perceptual and cognitive function, it is important to design behavioral paradigms for animal models to provide mechanistic insights into the neural bases of these multisensory processes. Prior studies have focused on large mammals, yet the mouse offers a host of advantages, most importantly the wealth of available genetic manipulations relevant to human disease. To begin to employ this model species for multisensory research it is necessary to first establish and validate a robust behavioral assay for the mouse. Two common mouse strains (C57BL/6J and 129S6/SvEv) were first trained to respond to unisensory (visual and auditory) stimuli separately. Once trained, performance with paired audiovisual stimuli was then examined with a focus on response accuracy and behavioral gain. Stimulus durations varied from 50 ms to 1 s in order to modulate the effectiveness of the stimuli and to determine if the well-established "principle of inverse effectiveness" held in this model. Response accuracy in the multisensory condition was greater than for either unisensory condition for all stimulus durations, with significant gains observed at the 300 ms and 100 ms durations. Main effects of stimulus duration, stimulus modality and a significant interaction between these factors were observed. The greatest behavioral gain was seen for the 100 ms duration condition, with a trend observed that as the stimuli became less effective, larger behavioral gains were observed upon their pairing (i.e., inverse effectiveness). These results are the first to validate the mouse as a species that shows demonstrable behavioral facilitations under multisensory conditions and provides a platform for future mechanistically directed studies to examine the neural bases of multisensory integration.

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