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1.
Thorax ; 79(8): 788-795, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38448221

RESUMO

BACKGROUND: Fibrotic interstitial lung diseases (fILDs) are a heterogeneous group of lung diseases associated with significant morbidity and mortality. Despite a large increase in the number of clinical trials in the last 10 years, current regulatory-approved management approaches are limited to two therapies that prevent the progression of fibrosis. The drug development pipeline is long and there is an urgent need to accelerate this process. This manuscript introduces the concept and design of an innovative research approach to drug development in fILD: a global Randomised Embedded Multifactorial Adaptive Platform in fILD (REMAP-ILD). METHODS: Description of the REMAP-ILD concept and design: the specific terminology, design characteristics (multifactorial, adaptive features, statistical approach), target population, interventions, outcomes, mission and values, and organisational structure. RESULTS: The target population will be adult patients with fILD, and the primary outcome will be a disease progression model incorporating forced vital capacity and mortality over 12 months. Responsive adaptive randomisation, prespecified thresholds for success and futility will be used to assess the effectiveness and safety of interventions. REMAP-ILD embraces the core values of diversity, equity, and inclusion for patients and researchers, and prioritises an open-science approach to data sharing and dissemination of results. CONCLUSION: By using an innovative and efficient adaptive multi-interventional trial platform design, we aim to accelerate and improve care for patients with fILD. Through worldwide collaboration, novel analytical methodology and pragmatic trial delivery, REMAP-ILD aims to overcome major limitations associated with conventional randomised controlled trial approaches to rapidly improve the care of people living with fILD.


Assuntos
Doenças Pulmonares Intersticiais , Humanos , Doenças Pulmonares Intersticiais/terapia , Progressão da Doença , Projetos de Pesquisa , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
J Vis ; 21(2): 8, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33595646

RESUMO

Categorization performance is a popular metric of scene recognition and understanding in behavioral and computational research. However, categorical constructs and their labels can be somewhat arbitrary. Derived from exhaustive vocabularies of place names (e.g., Deng et al., 2009), or the judgements of small groups of researchers (e.g., Fei-Fei, Iyer, Koch, & Perona, 2007), these categories may not correspond with human-preferred taxonomies. Here, we propose clustering by increasing the rand index via coordinate ascent (CIRCA): an unsupervised, data-driven clustering method for deriving ground-truth scene categories. In Experiment 1, human participants organized 80 stereoscopic images of outdoor scenes from the Southampton-York Natural Scenes (SYNS) dataset (Adams et al., 2016) into discrete categories. In separate tasks, images were grouped according to i) semantic content, ii) three-dimensional spatial structure, or iii) two-dimensional image appearance. Participants provided text labels for each group. Using the CIRCA method, we determined the most representative category structure and then derived category labels for each task/dimension. In Experiment 2, we found that these categories generalized well to a larger set of SYNS images, and new observers. In Experiment 3, we tested the relationship between our category systems and the spatial envelope model (Oliva & Torralba, 2001). Finally, in Experiment 4, we validated CIRCA on a larger, independent dataset of same-different category judgements. The derived category systems outperformed the SUN taxonomy (Xiao, Hays, Ehinger, Oliva, & Torralba, 2010) and an alternative clustering method (Greene, 2019). In summary, we believe this novel categorization method can be applied to a wide range of datasets to derive optimal categorical groupings and labels from psychophysical judgements of stimulus similarity.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Feminino , Humanos , Julgamento , Masculino , Psicofísica , Córtex Visual/fisiologia , Adulto Jovem
3.
J Neurosci ; 39(10): 1842-1854, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30626700

RESUMO

Rats trained to perform a version of the rat gambling task (rGT) in which salient audiovisual cues accompany reward delivery, similar to commercial gambling products, show greater preference for risky options. Given previous demonstrations that probabilistic reinforcement schedules can enhance psychostimulant-induced increases in accumbal DA and locomotor activity, we theorized that performing this cued task could perpetuate a proaddiction phenotype. Significantly more rats developed a preference for the risky options in the cued versus uncued rGT at baseline, and this bias was further exacerbated by cocaine self-administration, whereas the choice pattern of optimal decision-makers was unaffected. The addition of reward-paired cues therefore increased the proportion of rats exhibiting a maladaptive cognitive response to cocaine self-administration. Risky choice was not associated with responding for conditioned reinforcement or a marker of goal/sign-tracking, suggesting that reward-concurrent cues precipitate maladaptive choice via a unique mechanism unrelated to simple approach toward, or responding for, conditioned stimuli. Although "protected" from any resulting decision-making impairment, optimal decision-makers trained on the cued rGT nevertheless self-administered more cocaine than those trained on the uncued task. Collectively, these data suggest that repeated engagement with heavily cued probabilistic reward schedules can drive addiction vulnerability through multiple behavioral mechanisms. Rats trained on the cued rGT also exhibited blunted locomotor sensitization and lower basal accumbal DA levels, yet greater cocaine-induced increases in accumbal DA efflux. Gambling in the presence of salient cues may therefore result in an adaptive downregulation of the mesolimbic DA system, rendering individuals more sensitive to the deleterious effects of taking cocaine.SIGNIFICANCE STATEMENT Impaired cost/benefit decision making, exemplified by preference for the risky, disadvantageous options on the Iowa Gambling Task, is associated with greater risk of relapse and treatment failure in substance use disorder. Understanding factors that enhance preference for risk may help elucidate the neurobiological mechanisms underlying maladaptive decision making in addiction, thereby improving treatment outcomes. Problem gambling is also highly comorbid with substance use disorder, and many commercial gambling products incorporate salient win-paired cues. Here we show that adding reward-concurrent cues to a rat analog of the IGT precipitates a hypodopaminergic state, characterized by blunted accumbal DA efflux and attenuated locomotor sensitization, which may contribute to the enhanced responsivity to uncertain rewards or the reinforcing effects of cocaine we observed.


Assuntos
Comportamento Aditivo/fisiopatologia , Cocaína/administração & dosagem , Sinais (Psicologia) , Dopamina/metabolismo , Comportamento de Procura de Droga/fisiologia , Jogo de Azar/fisiopatologia , Núcleo Accumbens/fisiopatologia , Recompensa , Estimulação Acústica , Animais , Comportamento de Procura de Droga/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Masculino , Núcleo Accumbens/efeitos dos fármacos , Estimulação Luminosa , Ratos Long-Evans
4.
Brain Behav Immun ; 89: 339-349, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32688024

RESUMO

Lithium's efficacy in reducing both symptom severity in bipolar disorder (BD) and suicide risk across clinical populations may reflect its ability to reduce impulsivity. Changes in immune markers are associated with BD and suicidality yet their exact role in symptom expression remains unknown. Evidence also suggests that lithium may decrease levels of pro-inflammatory cytokines in the periphery and central nervous system, and that such changes are related to its therapeutic efficacy. However, issues of cause and effect are hard to infer from clinical data alone. Here, we investigated the effects of chronic dietary lithium treatment on rats' performance of the 5-Choice Serial Reaction Time Task (5CSRTT), a well-validated operant behavioural task measuring aspects of impulsivity, attention and motivation. Male Long-Evans rats received a diet supplemented with 0.3% LiCl (n = 13), or the equivalent control diet (n = 16), during behavioural testing. Blood and brain tissue samples were assayed for a wide range of cytokines once any changes in impulsivity became significant. After 12 weeks, chronic lithium treatment reduced levels of motor impulsivity, as indexed by premature responses in the 5CSRTT; measures of sustained attention and motivation were unaffected. Plasma levels of IL-1ß, IL-10 and RANTES (CCL-5) were reduced in lithium-treated rats at this time point. IL-1ß, IL-6 and RANTES were also reduced selectively within the orbitofrontal cortex of lithium-treated rats, whereas cytokine levels in the medial prefrontal cortex and nucleus accumbens were comparable with control subjects. These results are consistent with the hypothesis that lithium may improve impulse control deficits in clinical populations by minimising the effects of pro-inflammatory signalling on neuronal activity, particularly within the orbitofrontal cortex.


Assuntos
Citocinas , Lítio , Animais , Comportamento Impulsivo , Masculino , Córtex Pré-Frontal , Ratos , Ratos Long-Evans
5.
Proc Biol Sci ; 286(1896): 20182045, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30963917

RESUMO

Many species employ camouflage to disguise their true shape and avoid detection or recognition. Disruptive coloration is a form of camouflage in which high-contrast patterns obscure internal features or break up an animal's outline. In particular, edge enhancement creates illusory, or 'fake' depth edges within the animal's body. Disruptive coloration often co-occurs with background matching, and together, these strategies make it difficult for an observer to visually segment an animal from its background. However, stereoscopic vision could provide a critical advantage in the arms race between perception and camouflage: the depth information provided by binocular disparities reveals the true three-dimensional layout of a scene, and might, therefore, help an observer to overcome the effects of disruptive coloration. Human observers located snake targets embedded in leafy backgrounds. We analysed performance (response time) as a function of edge enhancement, illumination conditions and the availability of binocular depth cues. We confirm that edge enhancement contributes to effective camouflage: observers were slower to find snakes whose patterning contains 'fake' depth edges. Importantly, however, this effect disappeared when binocular depth cues were available. Illumination also affected detection: under directional illumination, where both the leaves and snake produced strong cast shadows, snake targets were localized more quickly than in scenes rendered under ambient illumination. In summary, we show that illusory depth edges, created via disruptive coloration, help to conceal targets from human observers. However, cast shadows and binocular depth information improve detection by providing information about the true three-dimensional structure of a scene. Importantly, the strong interaction between disparity and edge enhancement suggests that stereoscopic vision has a critical role in breaking camouflage, enabling the observer to overcome the disruptive effects of edge enhancement.


Assuntos
Cor , Reconhecimento Visual de Modelos , Pigmentação , Serpentes , Disparidade Visual , Adulto , Animais , Sinais (Psicologia) , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
6.
J Vis ; 19(6): 2, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31166580

RESUMO

People are able to perceive the 3D shape of illuminated surfaces using image shading cues. Theories about how we accomplish this often assume that the human visual system estimates a single lighting direction and interprets shading cues in accord with that estimate. In natural scenes, however, lighting can be much more complex than this, with multiple nearby light sources. Here we show that the human visual system can successfully judge 3D surface shape even when the lighting direction varies from place to place over a surface, provided the scale at which these lighting changes occur is similar to, or larger than, the size of the shape features being judged. Furthermore, we show that despite being able to accommodate rapid changes in lighting direction when judging shape, observers are generally unable to detect these changes. We conclude that, rather than relying on a single estimated illumination direction, the human visual system can accommodate illumination that varies substantially and rapidly across a surface.


Assuntos
Percepção de Forma/fisiologia , Iluminação , Feminino , Humanos , Imageamento Tridimensional , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
7.
Behav Pharmacol ; 29(8): 732-744, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30376458

RESUMO

Multiline slot machines encourage continued play through 'losses disguised as wins' (LDWs), outcomes in which the money returned is less than that wagered. Individuals with gambling problems may be susceptible to this game feature. The cognitive and neurobiological mechanisms through which LDWs act are unknown. In a novel rat operant task, animals chose between a 'certain' lever, which always delivered two sugar pellets, or an 'uncertain' lever, resulting in four sugar pellets on 50% of trials. LDWs were then introduced as a return of three sugar pellets on 30-40% of uncertain rewarded trials. For half the rats, winning outcomes were paired with audiovisual feedback (cues). In a second study, the basolateral amygdala (BLA) was inactivated during initial presentation of LDWs. While LDWs shifted most rats' choice toward the certain lever, a subgroup of LDW vulnerable rats continued to choose the uncertain option, when the reward rate diminished. This profile of LDW vulnerability was reproduced after inactivating the BLA. Persistent choice of uncertain outcomes despite lower reward rates may reflect impaired functioning within the BLA. Future work using this model may provide insight into the neurobiological mechanisms contributing to the motivational properties of LDWs and their contribution to problematic gambling.


Assuntos
Tomada de Decisões/fisiologia , Extinção Psicológica/fisiologia , Motivação/fisiologia , Análise de Variância , Animais , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Complexo Nuclear Basolateral da Amígdala/fisiologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Tomada de Decisões/efeitos dos fármacos , Extinção Psicológica/efeitos dos fármacos , Agonistas GABAérgicos/farmacologia , Masculino , Microinjeções , Motivação/efeitos dos fármacos , Ratos , Ratos Long-Evans , Reforço Psicológico
8.
J Vis ; 18(13): 4, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30508429

RESUMO

Recognizing materials and understanding their properties is very useful-perhaps critical-in daily life as we encounter objects and plan our interactions with them. Visually derived estimates of material properties guide where and with what force we grasp an object. However, the estimation of material properties, such as glossiness, is a classic ill-posed problem. Image cues that we rely on to estimate gloss are also affected by shape, illumination and, in visual displays, tone-mapping. Here, we focus on the latter two. We define some commonalities present in the structure of natural illumination, and determine whether manipulation of these natural "signatures" impedes gloss constancy. We manipulate the illumination field to violate statistical regularities of natural illumination, such that light comes from below, or the luminance distribution is no longer skewed. These manipulations result in errors in perceived gloss. Similarly, tone mapping has a dramatic effect on perceived gloss. However, when objects are viewed against an informative (rather than plain gray) background that reflects these manipulations, there are some improvements to gloss constancy: in particular, observers are far less susceptible to the effects of tone mapping when judging gloss. We suggest that observers are sensitive to some very simple statistics of the environment when judging gloss.


Assuntos
Iluminação , Propriedades de Superfície , Percepção Visual/fisiologia , Sensibilidades de Contraste/fisiologia , Sinais (Psicologia) , Percepção de Forma/fisiologia , Humanos , Estimulação Luminosa
9.
Eur J Neurosci ; 45(1): 159-166, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27422144

RESUMO

D2/3 receptor agonists are effective treatments for Parkinson's disease (PD), but can precipitate impulse control disorders (ICDs) including gambling disorder (GD). The neurobiological mechanisms underlying this devastating side-effect of dopamine agonist replacement therapy (DRT), and any dependence on the dopamine depletion caused by PD, are unclear. It is also unclear whether previous biases towards risk or uncertainty are a risk factor for developing these ICDs. We investigated whether chronic D2/3 agonist administration (5 mg/kg/day ropinirole for 28 days) altered performance of a rat model of gambling-like behaviour, the rodent betting task (rBT), and examined if baseline behaviour predicted this behavioural change. The rBT captures individual differences in subjective preference for uncertain outcomes: animals choose between guaranteed or probabilistic reinforcement of equal expected value. Chronic ropinirole dramatically increased selection of the uncertain option in two-thirds of animals, regardless of baseline preferences. The effect on choice in the rBT was replicated in a dorsolateral striatal 6-hydroxydopamine (6-OHDA) rat model of early PD. These studies are the first to look at individual differences in response to chronic, rather than pulsatile, dosing of DRT in a rodent model of gambling behaviour. These findings suggest that DRT-induced PG may stem from increases in subjective valuation of uncertainty. Such symptoms likely arise because of changes in dopaminergic striatal signalling caused by DRT rather than from an interaction between pre-morbid behaviours or PD itself.


Assuntos
Comportamento de Escolha/efeitos dos fármacos , Corpo Estriado/metabolismo , Agonistas de Dopamina/farmacologia , Indóis/farmacologia , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Incerteza , Animais , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Masculino , Neostriado/metabolismo , Oxidopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Ratos Long-Evans
10.
J Psychiatry Neurosci ; 42(2): 131-138, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28245177

RESUMO

BACKGROUND: Acceptance of cannabis use is growing. However, prolonged use is associated with diminished psychosocial outcomes, potentially mediated by drug-induced cognitive impairments. Δ9-Tetrahydrocannabinol (THC) is the main psychoactive ingredient in cannabis, yet other phytocannabinoids in the plant, such as cannabidiol (CBD), have unique properties. Given that CBD can modulate the undesirable effects of THC, therapeutic agents, such as nabiximols, contain higher CBD:THC ratios than illicit marijuana. We tested the hypothesis that THC impairs a relevant cognitive function for long-term success, namely willingness to exert cognitive effort for greater rewards, and that CBD could attenuate such decision-making impairments. METHODS: Male Long-Evans rats (n = 29) performing the rat cognitive effort task (rCET) received acute THC and CBD, independently and concurrently, in addition to other cannabinoids. Rats chose between 2 options differing in reward magnitude, but also in the cognitive effort (attentional load) required to obtain them. RESULTS: We found that THC decreased choice of hard trials without impairing the animals' ability to accurately complete them. Strikingly, this impairment was correlated with CB1 receptor density in the medial prefrontal cortex - an area previously implicated in effortful decision-making. In contrast, CBD did not affect choice. Coadministration of 1:1 CBD:THC matching that in nabiximols modestly attenuated the deleterious effects of THC in "slacker" rats. LIMITATIONS: Only male rats were investigated, and the THC/CBD coadministration experiment was carried out in a subset of individuals. CONCLUSION: These findings confirm that THC, but not CBD, selectively impairs decision-making involving cognitive effort costs. However, coadministration of CBD only partially ameliorates such THC-induced dysfunction.


Assuntos
Atenção/efeitos dos fármacos , Cognição/efeitos dos fármacos , Tomada de Decisões/efeitos dos fármacos , Dronabinol/farmacologia , Motivação/efeitos dos fármacos , Psicotrópicos/farmacologia , Animais , Atenção/fisiologia , Canabidiol/farmacologia , Moduladores de Receptores de Canabinoides/farmacologia , Cognição/fisiologia , Tomada de Decisões/fisiologia , Relação Dose-Resposta a Droga , Masculino , Motivação/fisiologia , Testes Neuropsicológicos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos Long-Evans , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/antagonistas & inibidores , Recompensa
11.
PLoS Comput Biol ; 12(4): e1004865, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27078834

RESUMO

Adults combine information from different sensory modalities to estimate object properties such as size or location. This process is optimal in that (i) sensory information is weighted according to relative reliability: more reliable estimates have more influence on the combined estimate and (ii) the combined estimate is more reliable than the component uni-modal estimates. Previous studies suggest that optimal sensory integration does not emerge until around 10 years of age. Younger children rely on a single modality or combine information using inappropriate sensory weights. Children aged 4-11 and adults completed a simple audio-visual task in which they reported either the number of beeps or the number of flashes in uni-modal and bi-modal conditions. In bi-modal trials, beeps and flashes differed in number by 0, 1 or 2. Mutual interactions between the sensory signals were evident at all ages: the reported number of flashes was influenced by the number of simultaneously presented beeps and vice versa. Furthermore, for all ages, the relative strength of these interactions was predicted by the relative reliabilities of the two modalities, in other words, all observers weighted the signals appropriately. The degree of cross-modal interaction decreased with age: the youngest observers could not ignore the task-irrelevant modality-they fully combined vision and audition such that they perceived equal numbers of flashes and beeps for bi-modal stimuli. Older observers showed much smaller effects of the task-irrelevant modality. Do these interactions reflect optimal integration? Full or partial cross-modal integration predicts improved reliability in bi-modal conditions. In contrast, switching between modalities reduces reliability. Model comparison suggests that older observers employed partial integration, whereas younger observers (up to around 8 years) did not integrate, but followed a sub-optimal switching strategy, responding according to either visual or auditory information on each trial.


Assuntos
Percepção Auditiva , Julgamento , Modelos Psicológicos , Percepção Visual , Estimulação Acústica , Adolescente , Adulto , Envelhecimento/psicologia , Criança , Pré-Escolar , Biologia Computacional , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
12.
J Child Psychol Psychiatry ; 57(8): 917-26, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26934047

RESUMO

BACKGROUND: Previous research has reported altered emotion recognition in both conduct disorder (CD) and anxiety disorders (ADs) - but these effects appear to be of different kinds. Adolescents with CD often show a generalised pattern of deficits, while those with ADs show hypersensitivity to specific negative emotions. Although these conditions often cooccur, little is known regarding emotion recognition performance in comorbid CD+ADs. Here, we test the hypothesis that in the comorbid case, anxiety-related emotion hypersensitivity counteracts the emotion recognition deficits typically observed in CD. METHOD: We compared facial emotion recognition across four groups of adolescents aged 12-18 years: those with CD alone (n = 28), ADs alone (n = 23), cooccurring CD+ADs (n = 20) and typically developing controls (n = 28). The emotion recognition task we used systematically manipulated the emotional intensity of facial expressions as well as fixation location (eye, nose or mouth region). RESULTS: Conduct disorder was associated with a generalised impairment in emotion recognition; however, this may have been modulated by group differences in IQ. AD was associated with increased sensitivity to low-intensity happiness, disgust and sadness. In general, the comorbid CD+ADs group performed similarly to typically developing controls. CONCLUSIONS: Although CD alone was associated with emotion recognition impairments, ADs and comorbid CD+ADs were associated with normal or enhanced emotion recognition performance. The presence of comorbid ADs appeared to counteract the effects of CD, suggesting a potentially protective role, although future research should examine the contribution of IQ and gender to these effects.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Transtornos de Ansiedade/fisiopatologia , Transtorno da Conduta/fisiopatologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Adolescente , Transtornos de Ansiedade/epidemiologia , Criança , Comorbidade , Transtorno da Conduta/epidemiologia , Feminino , Humanos , Masculino
13.
J Psychiatry Neurosci ; 41(6): 150363, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27557094

RESUMO

BACKGROUND: Acceptance of cannabis use is growing. However, prolonged use is associated with diminished psychosocial outcomes, potentially mediated by drug-induced cognitive impairments. Δ9-Tetrahydrocannabinol (THC) is the main psychoactive ingredient in cannabis, yet other phytocannabinoids in the plant, such as cannabidiol (CBD), have unique properties. Given that CBD can modulate the undesirable effects of THC, therapeutic agents, such as nabiximols, contain higher CBD:THC ratios than illicit marijuana. We tested the hypothesis that THC impairs a relevant cognitive function for long-term success, namely willingness to exert cognitive effort for greater rewards, and that CBD could attenuate such decision-making impairments. METHODS: Male Long-Evans rats (n = 29) performing the rat cognitive effort task (rCET) received acute THC and CBD, independently and concurrently, in addition to other cannabinoids. Rats chose between 2 options differing in reward magnitude, but also in the cognitive effort (attentional load) required to obtain them. RESULTS: We found that THC decreased choice of hard trials without impairing the animals' ability to accurately complete them. Strikingly, this impairment was correlated with CB1 receptor density in the medial prefrontal cortex - an area previously implicated in effortful decision-making. In contrast, CBD did not affect choice. Coadministration of 1:1 CBD:THC matching that in nabiximols modestly attenuated the deleterious effects of THC in "slacker" rats. LIMITATIONS: Only male rats were investigated, and the THC/CBD coadministration experiment was carried out in a subset of individuals. CONCLUSION: These findings confirm that THC, but not CBD, selectively impairs decision-making involving cognitive effort costs. However, coadministration of CBD only partially ameliorates such THC-induced dysfunction.

14.
Eur J Neurosci ; 42(12): 3095-104, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26527415

RESUMO

High impulsivity, mediated through ventral striatal dopamine signalling, represents an established risk factor for substance abuse, and may likewise confer vulnerability to pathological overeating. Mechanistically, the assumption is that trait impulsivity facilitates the initiation of maladaptive eating styles or choices. However, whether consumption of appetitive macronutrients themselves causes deficits in impulse control and striatal signalling, thereby contributing to cognitive changes permissive of overeating behaviour, has yet to be considered. We examined the effects of chronic maintenance on restricted equicaloric, but high-fat or high-sugar, diets (48 kcal/day; 60 kcal% fat or sucrose) on rats' performance in the five-choice serial reaction time task, indexing impulsivity and attention. Markers of dopamine signalling in the dorsal and ventral striatum, and plasma insulin and leptin levels, were also assessed. Rats maintained on the high-fat diet (HFD) were more impulsive, whereas the high-sugar diet (HSD) did not alter task performance. Importantly, body weight and hormone levels were similar between groups when behavioural changes were observed. Maintenance on HFD, but not on HSD, reduced the levels of dopamine D2 receptor (D2 R), cAMP response element-binding protein (CREB) and phosphophorylated CREB (Ser133) proteins in the ventral, but not dorsal, striatum. D2 R expression in the ventral striatum also negatively correlated with impulsive responding, independently of diet. These data indicate that chronic exposure to even limited amounts of high-fat foods may weaken impulse control and alter neural signalling in a manner associated with vulnerability to addictions - findings that have serious implications for the propagation of uncontrolled eating behaviour in obesity and binge-eating disorder.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Dieta Redutora/efeitos adversos , Comportamento Impulsivo/fisiologia , Receptores de Dopamina D2/metabolismo , Estriado Ventral/fisiopatologia , Animais , Atenção/fisiologia , Análise Química do Sangue , Peso Corporal , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Sacarose Alimentar/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Função Executiva/fisiologia , Immunoblotting , Inibição Psicológica , Insulina/sangue , Leptina/sangue , Masculino , Atividade Motora/fisiologia , Ratos Long-Evans , Fatores de Tempo
15.
PLoS Comput Biol ; 10(5): e1003576, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24811069

RESUMO

Shading is known to produce vivid perceptions of depth. However, the influence of specular highlights on perceived shape is unclear: some studies have shown that highlights improve quantitative shape perception while others have shown no effect. Here we ask how specular highlights combine with Lambertian shading cues to determine perceived surface curvature, and to what degree this is based upon a coherent model of the scene geometry. Observers viewed ambiguous convex/concave shaded surfaces, with or without highlights. We show that the presence/absence of specular highlights has an effect on qualitative shape, their presence biasing perception toward convex interpretations of ambiguous shaded objects. We also find that the alignment of a highlight with the Lambertian shading modulates its effect on perceived shape; misaligned highlights are less likely to be perceived as specularities, and thus have less effect on shape perception. Increasing the depth of the surface or the slant of the illuminant also modulated the effect of the highlight, increasing the bias toward convexity. The effect of highlights on perceived shape can be understood probabilistically in terms of scene geometry: for deeper objects and/or highly slanted illuminants, highlights will occur on convex but not concave surfaces, due to occlusion of the illuminant. Given uncertainty about the exact object depth and illuminant direction, the presence of a highlight increases the probability that the surface is convex.


Assuntos
Sensibilidades de Contraste/fisiologia , Sinais (Psicologia) , Percepção de Forma/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Iluminação/métodos , Modelos Biológicos , Disparidade Visual/fisiologia , Animais , Simulação por Computador , Humanos
16.
BMJ Open Respir Res ; 11(1)2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413120

RESUMO

OBJECTIVES: Mycophenolate mofetil (MMF) and azathioprine (AZA) are immunomodulatory treatments in interstitial lung disease (ILD). This systematic review aimed to evaluate the efficacy of MMF or AZA on pulmonary function in ILD. DESIGN: Population included any ILD diagnosis, intervention included MMF or AZA treatment, outcome was delta change from baseline in per cent predicted forced vital capacity (%FVC) and gas transfer (diffusion lung capacity of carbon monoxide, %DLco). The primary endpoint compared outcomes relative to placebo comparator, the secondary endpoint assessed outcomes in treated groups only. ELIGIBILITY CRITERIA: Randomised controlled trials (RCTs) and prospective observational studies were included. No language restrictions were applied. Retrospective studies and studies with high-dose concomitant steroids were excluded. DATA SYNTHESIS: The systematic search was performed on 9 May. Meta-analyses according to drug and outcome were specified with random effects, I2 evaluated heterogeneity and Grading of Recommendations, Assessment, Development and Evaluation evaluated certainty of evidence. Primary endpoint analysis was restricted to RCT design, secondary endpoint included subgroup analysis according to prospective observational or RCT design. RESULTS: A total of 2831 publications were screened, 12 were suitable for quantitative synthesis. Three MMF RCTs were included with no significant effect on the primary endpoints (%FVC 2.94, 95% CI -4.00 to 9.88, I2=79.3%; %DLco -2.03, 95% CI -4.38 to 0.32, I2=0.0%). An overall 2.03% change from baseline in %FVC (95% CI 0.65 to 3.42, I2=0.0%) was observed in MMF, and RCT subgroup summary estimated a 4.42% change from baseline in %DLCO (95% CI 2.05 to 6.79, I2=0.0%). AZA studies were limited. All estimates were considered very low certainty evidence. CONCLUSIONS: There were limited RCTs of MMF or AZA and their benefit in ILD was of very low certainty. MMF may support preservation of pulmonary function, yet confidence in the effect was weak. To support high certainty evidence, RCTs should be designed to directly assess MMF efficacy in ILD. PROSPERO REGISTRATION NUMBER: CRD42023423223.


Assuntos
Azatioprina , Doenças Pulmonares Intersticiais , Humanos , Azatioprina/uso terapêutico , Azatioprina/farmacologia , Imunossupressores/uso terapêutico , Doenças Pulmonares Intersticiais/diagnóstico , Pulmão , Ácido Micofenólico/uso terapêutico , Ácido Micofenólico/farmacologia , Inibidores Enzimáticos/uso terapêutico , Estudos Observacionais como Assunto
17.
BMJ Open Respir Res ; 11(1)2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418384

RESUMO

INTRODUCTION: Remote monitoring of home physiological measurements has been proposed as a solution to support patients with chronic diseases as well as facilitating virtual consultations and pandemic preparedness for the future. Daily home spirometry and pulse oximetry have been demonstrated to be safe and acceptable to patients with interstitial lung disease (ILD) but there is currently limited evidence to support its integration into clinical practice. AIM: Our aim is to understand the clinical utility of frequent remote physiological measurements in ILD and the impact of integrating these into clinical practice from a patient, clinical and health economic perspective. METHODS AND ANALYSIS: 132 patients with fibrotic ILD will be recruited and randomised to receive either usual care with remote digital monitoring of home spirometry and pulse oximetry or usual care alone for 12 months. All participants will complete health-related quality of life and experience questionnaires.The primary outcome compares the availability of spirometry measurements within the 2 weeks preceding planned clinic appointments. Secondary outcomes will explore other aspects of clinical and cost-effectiveness of the remote monitoring programme. ETHICS AND DISSEMINATION: The study has been approved by the Camden and Kings Cross Research Ethics Committee (22/LO/0309). All participants will provide informed consent.This study is registered with www. CLINICALTRIALS: gov (NCT05662124).The results of the study will be submitted for presentation at regional and national conferences and submitted for peer-reviewed publication. Reports will be prepared for study participants with the support from our public involvement representatives through the charity Action for Pulmonary Fibrosis.


Assuntos
Doenças Pulmonares Intersticiais , Qualidade de Vida , Humanos , Análise Custo-Benefício , Resultado do Tratamento , Doenças Pulmonares Intersticiais/diagnóstico , Oximetria , Espirometria , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
18.
Hum Brain Mapp ; 34(8): 1982-98, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22451259

RESUMO

Sensorimotor regions of the brain have been implicated in simulation processes such as action understanding and empathy, but their functional role in these processes remains unspecified. We used functional magnetic resonance imaging (fMRI) to demonstrate that postcentral sensorimotor cortex integrates action and object information to derive the sensory outcomes of observed hand-object interactions. When subjects viewed others' hands grasping or withdrawing from objects that were either painful or nonpainful, distinct sensorimotor subregions emerged as showing preferential responses to different aspects of the stimuli: object information (noxious vs. innocuous), action information (grasps vs. withdrawals), and painful action outcomes (painful grasps vs. all other conditions). Activation in the latter region correlated with subjects' ratings of how painful each object would be to touch and their previous experience with the object. Viewing others' painful grasps also biased behavioral responses to actual tactile stimulation, a novel effect not seen for auditory control stimuli. Somatosensory cortices, including primary somatosensory areas 1/3b and 2 and parietal area PF, may therefore subserve somatomotor simulation processes by integrating action and object information to anticipate the sensory consequences of observed hand-object interactions.


Assuntos
Mapeamento Encefálico , Emoções/fisiologia , Empatia/fisiologia , Dor , Córtex Somatossensorial/fisiologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Adulto Jovem
19.
Bioelectromagnetics ; 34(4): 275-84, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23355058

RESUMO

Adolescence is a critical developmental stage during which substantial remodeling occurs in brain areas involved in emotional and learning processes. Although a robust literature on the biological effects of extremely low frequency magnetic fields (ELF-MFs) has been documented, data on the effects of ELF-MF exposure during this period on cognitive functions remain scarce. In this study, early adolescent male mice were exposed from postnatal day (P) 23-35 to a 50 Hz MF at 2 mT for 60 min/day. On P36-45, the potential effects of the MF exposure on spatial memory performance were examined using the Y-maze and Morris water maze tasks. The results showed that the MF exposure did not affect Y-maze performance but improved spatial learning acquisition and memory retention in the water maze task under the present experimental conditions.


Assuntos
Crescimento e Desenvolvimento , Campos Magnéticos/efeitos adversos , Memória , Comportamento Espacial/fisiologia , Animais , Tamanho Corporal , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos
20.
J Vis ; 13(1): 9, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23291649

RESUMO

Glossy and matte objects can be differentiated using specular highlights: bright patches in the retinal image produced when light rays are reflected regularly from smooth surfaces. However, bright patches also occur on matte objects, due to local illumination or reflectance changes. Binocular vision provides information that could distinguish specular highlights from other luminance discontinuities; unlike surface markings, specular highlights lie not at the surface depth, but "float" in front of concave surfaces and behind convex ones. We ask whether observers implicitly understand and exploit the peculiarities of specular geometry for gloss and shape perception. Our participants judged the glossiness and shape of curved surfaces that included specular highlights at various depths. Observers demonstrated substantial deviations from a full geometric model of specular reflection. Concave surfaces appeared glossy both when highlights lay in front of and (incorrectly) behind the surface. Failings in the interpretation of monocular highlights were also apparent. Highlight disparity had no effect on shape perception. However, the perceived gloss of convex surfaces did follow geometric constraints: only highlights at appropriate depths produced high gloss ratings. We suggest, in contrast with previous work, that the visual system invokes simple heuristics as gloss indicators to accommodate complex reflections and inter-reflections that occur particularly inside concavities.


Assuntos
Percepção de Profundidade/fisiologia , Percepção de Forma/fisiologia , Modelos Teóricos , Psicofísica/métodos , Visão Binocular/fisiologia , Adulto , Sensibilidades de Contraste/fisiologia , Feminino , Humanos , Luz , Masculino , Estimulação Luminosa/métodos , Propriedades de Superfície
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