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1.
Am J Ther ; 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37820082

RESUMEN

BACKGROUND: Loop diuretic therapy effectively treats edema related to heart failure, chronic kidney disease, and liver impairment; however, evidence supporting other indications is lacking. For indications such as hypertension or dependent edema or treatment of adverse events associated with other medications, the benefits likely do not outweigh the risks, putting patients at an unacceptably high risk of poor outcomes. STUDY QUESTION: What is the proportion of loop diuretic prescribing that occurs in the absence of a diagnosis of heart failure, chronic kidney disease, liver impairment, or other evidence-based indications? STUDY DESIGN: This was a national, retrospective, cross-sectional investigation conducted using the National Ambulatory Care Survey from 2013 to 2016. Outpatient visits for patients aged 18 years or older prescribed with loop diuretics were included. MEASURES AND OUTCOMES: The primary end point was the frequency of potentially inappropriate loop diuretic prescribing. The secondary end point was a multivariable regression model that identified predictors of potentially inappropriate loop diuretic utilization. RESULTS: This analysis identified 5261 outpatient visits conducted during the study period in which loop diuretics were prescribed. Of these, 3648 visits (65.8% of weighted visits) were of patients without a history of heart failure, chronic kidney disease, or liver impairment. Positive predictors included age older than 65 years (odds ratio [OR] 1.71; 95% confidence interval [CI] 1.38-2.13), concomitant calcium channel blocker (OR 1.42; 95% CI, 1.09-1.84), sodium-containing medication use (OR 2.78; 95% CI, 1.23-6.25), and office visit with a cardiology specialist (OR 2.84; 95% CI, 2.31-3.50). CONCLUSIONS: This analysis identified that loop diuretics are prescribed in the absence of evidence-based indications more frequently than they are prescribed for them. This prescribing pattern creates a unique opportunity for clinicians to optimize patient care. Further study of the outcomes associated with this prescribing pattern is warranted.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37569046

RESUMEN

This paper examines factors correlated with online self-help-an informal form of social control vis-à-vis intervention-upon witnessing a cyberhate attack. Using online surveys from 18- to 26-year-old respondents in the United States, we explore the roles of various types of online and offline formal and informal social control mechanisms on the enactment of self-help through the use of descriptive statistics and ordinal logistic regression. The results of the multivariate analyses indicate that online collective efficacy is positively related to self-help, as is having close ties to individuals and groups offline and online. Formal online social control, however, is not significantly related to engaging in self-help. Other findings demonstrate that personal encounters with cyberhate affect the likelihood that an individual will intervene when witnessing an attack, and that individuals with high levels of empathy are more likely to intervene to assist others. This work indicates that pro-social online behavior is contagious and can potentially foster online spaces in which harmful behaviors, such as propagating cyberhate, are not condoned.


Asunto(s)
Empatía , Conducta Social , Humanos , Adolescente , Adulto Joven , Adulto , Encuestas y Cuestionarios
3.
Cyberpsychol Behav Soc Netw ; 26(7): 546-553, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37462919

RESUMEN

Hate crimes and hateful rhetoric targeting individuals of Asian descent have increased since the outbreak of COVID-19. These troubling trends have heightened concerns about the role of the Internet in facilitating radicalization. This article explores the existence of three warning signs of radicalization-fixation, group identification, and energy bursts-using data from Twitter and Reddit. Data were collected before and after the outbreak of COVID-19 to assess the role of the pandemic in affecting social media behavior. Using computational social science and Natural Language Processing techniques, we looked for signs of radicalization targeting China or Chinese individuals. Results show that fixation on the terms China and Chinese increased on Twitter and Reddit after the pandemic began. Moreover, tweets and posts containing either of these terms became more hateful, offensive, and negative after the outbreak. We also found evidence of individuals identifying more closely with a particular group, or adopting an "us vs. them" mentality, after the outbreak of COVID-19. These findings were especially prominent in subreddits catering to self-identified Republicans and Conservatives. Finally, we detected bursts of activity on Twitter and Reddit following the start of the pandemic. These warning signs suggest COVID-19 may have had a radicalizing effect on some social media users. This work is important because it not only shows the potential radicalizing effect of the pandemic, but also demonstrates the ability to detect warning signs of radicalization on social media. This is critical, as detecting warning signs of radicalization can potentially help curb hate-fueled violence.


Asunto(s)
COVID-19 , Racismo , Medios de Comunicación Sociales , Humanos , Pueblo Asiatico , Odio
4.
Mem Cognit ; 51(8): 1870-1880, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37204674

RESUMEN

Growing evidence has revealed the crucial role of motor simulation and spatial perspective-taking in action language. However, there is still a lack of understanding of how motor and spatial processes interact when there are multiple actors involved, and if embodied processes are consistent across different cultures. To address this gap, we examined the interaction between motor simulation and spatial perspective-taking in action-sentences comprehension, along with the consistency of embodied processes across cultures. We collected data from Italian and US English speakers using an online sentence-picture verification task. The participants completed four conditions: two congruent (i.e., the participant is the agent in the sentence and the photo; the agent is someone else interacting with the participant in both the sentence and the picture) and two incongruent (i.e., the agents of the sentence and the picture do not match). The results show that when the perspective of the picture matched that described in the sentence-processing reaction times (RTs) were faster than in the incongruent conditions. In the congruent conditions where the agent is someone else, RTs were slower compared to the condition where the participant is the agent. This has been interpreted as claiming that motor simulation and perspective-taking are independent processes interacting during sentence comprehension (e.g., motor simulation is always run in the role of the agent, but we can adopt multiple perspectives depending on the pronouns and the contextual cues). Furthermore, Bayesian analysis provided evidence that embodied processing of action language entwines a common mechanism, suggesting cross-cultural consistency of embodied processes.


Asunto(s)
Comprensión , Comparación Transcultural , Humanos , Teorema de Bayes , Lenguaje , Tiempo de Reacción
5.
Community Ment Health J ; 59(3): 578-594, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36322279

RESUMEN

The Sequential Intercept Model has helped conceptualize interventions for people with serious mental illness in the criminal/legal system. This paper operationalizes the Sequential Intercept Model into a 35-item scorecard of behavioral health and legal practices. Using interviews, survey, and observational methods, the scorecard assesses an exploratory sample of 19 counties over 27 independent data collections. A series of ordinary least squares regression models assessed the predictor scores on four jail outcomes: prevalence of serious mental illness, length of stay, connections to treatment, and recidivism. Increases in pre-booking scores showed significant decreases in jail prevalence of serious mental illness at the p < 0.05 level, and post-booking scores and overall scores showed significant positive associations with connections to treatment at the p < 0.05 level, though these were non-significant after correcting for multiple comparisons. Preliminary findings suggest a combination of practices across the Sequential Intercept Model could have synergistic impacts on key jail diversion outcomes.


Asunto(s)
Trastornos Mentales , Prisioneros , Psiquiatría , Humanos , Trastornos Mentales/epidemiología , Trastornos Mentales/terapia , Liderazgo , Derecho Penal
6.
Appl Neuropsychol Adult ; : 1-12, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35570656

RESUMEN

Simulated driving offers a convenient test of driving ability for older drivers, although the viability of using simulated driving with this population is mixed. The relative weighting of the relevant perceptual, cognitive, and physical factors may vary between simulated and on-road driving. The current study was designed to assess this possibility. We conducted simulated and on-road driving tests of 61 older adults aged 66-92 years. To ensure that the driving performance was measured similarly between the two driving modalities, we employed the Record of Driving Errors (RODE) driving assessment system during both driving tests. Correlation and random weights analysis (RWA) results indicated only modest evidence of correspondence between the simulated and on-road driving performances. The primary factors operative in both simulated and on-road driving was Useful Field of View and a measure of basic cognition. Unique factors for simulated driving included a measure of physical mobility (Time-Up-and-Go) and spatial reasoning (Line), and for on-road driving included chronological age and sensorimotor processing (Trail-Making Task A). Chronological age was correlated primarily the on-road rather than simulated test, was greatly reduced with the inclusion of additional explanatory factors, and likely reflects driving efficiency rather than driving safety. We conclude that simulated driving in healthy older drivers can be beneficial for research purposes to assess cognitive and perceptual factors that underly driving effectiveness, although it cannot serve as a clear proxy for on-road driving.

7.
J Subst Abuse Treat ; 138: 108751, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35241352

RESUMEN

INTRODUCTION: The overdose epidemic persists as a public health crisis in the United States. Jails are a critical overdose prevention touchpoint. The risk of overdose postincarceration may be increased if an individual is released without medication for opioid use disorder (MOUD) treatment or transferred to long-term residential treatment. A growing number of studies have examined the difficulties in implementing evidence-based care for opioid use disorder (OUD) in jail settings. METHODS: We use administrative data (July 1, 2020, through September 30, 2020) from four jail facilities that implemented OUD treatment programs. These data included screening data from the Rapid Opioid Dependence Screener (RODS) (n = 2562), along with booking and medication information from jail records, which we used to develop a cascade-of-care. RESULTS: Screening rates varied dramatically by facility, with integration into the jail records management system showing the best outcomes. The prevalence of OUD identified from the RODS was 8.1% and did not vary significantly by facility. Nearly one third (31.3%) of those identified as having an OUD were dispensed medications, with two-thirds receiving methadone and the remaining third buprenorphine. The average length of stay for all screened individuals was two weeks, compared to two months for those who received an MOUD. CONCLUSIONS: Screening for OUD diagnosis is critical to reduce gaps in a cascade-of-care, and our results provide guidance on how to achieve this in jail. Failing to identify OUD and provide MOUD places an individual at an increased risk for fatal overdose. Future studies should consider examining MOUD discharge planning and factors that improve treatment retention following release from incarceration. Our study also illustrates the churn of jail populations and the need for rapid induction of treatment and overdose prevention strategies upon release.


Asunto(s)
Buprenorfina , Sobredosis de Droga , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Buprenorfina/uso terapéutico , Sobredosis de Droga/tratamiento farmacológico , Sobredosis de Droga/epidemiología , Humanos , Cárceles Locales , Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Estados Unidos
8.
Artículo en Inglés | MEDLINE | ID: mdl-35010794

RESUMEN

The Internet, specifically social media, is among the most common settings where young people encounter hate speech. Understanding their attitudes toward the phenomenon is crucial for combatting it because acceptance of such content could contribute to furthering the spread of hate speech as well as ideology contamination. The present study, theoretically grounded in the General Aggression Model (GAM), investigates factors associated with online hate acceptance among young adults. We collected survey data from participants aged 18-26 from six countries: Finland (n = 483), France (n = 907), Poland (n = 738), Spain (n = 739), the United Kingdom (n = 959), and the United States (n = 1052). Results based on linear regression modeling showed that acceptance of online hate was strongly associated with acceptance of violence in all samples. In addition, participants who admitted to producing online hate reported higher levels of acceptance of it. Moreover, association with social dominance orientation was found in most of the samples. Other sample-specific significant factors included participants' experiences with the Internet and online hate, as well as empathy and institutional trust levels. Significant differences in online hate acceptance levels and the strength of its connections to individual factors were found between the countries. These results provide important insights into the phenomenon, demonstrating that online hate acceptance is part of a larger belief system and is influenced by cultural background, and, therefore, it cannot be analyzed or combatted in isolation from these factors.


Asunto(s)
Odio , Medios de Comunicación Sociales , Adolescente , Agresión , Humanos , Habla , Violencia , Adulto Joven
9.
Psychol Aging ; 35(4): 565-577, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32105110

RESUMEN

Visual working memory (VWM) is an essential aspect of cognitive functioning that becomes compromised in older adults. A canonical probe of VWM is the change detection task in which participants compare a visually presented stimulus with items being maintained in VWM. Older adults show a decreased ability to detect changes between a stimulus and the contents of VWM compared with younger adults. Previously, we used a dynamic neural field (DNF) model to explore changes in neural connectivity that can explain this pattern of decline in performance. These simulations suggest that older adults have cortical interactions that are more diffuse compared to younger adults. In the current article, we examined the precision of representations in VWM using the delayed-estimation task. Participants are first presented with a memory array. After a delay, a location is cued, and participants click on a color wheel to indicate which color was at that location. The model predicted that older adults should show increased guessing rates and decreased precision (defined as the variability of color responses around the target location) relative to younger adults. The model also predicted that presenting the nontarget items during test should improve the precision of responses for older adults but not for younger adults. Results from two experiments supported these predictions of the model. These findings further advance an emerging theory of the neurocognitive decline of VWM and illustrate how older adults' VWM representations are influenced by the context in which information is being recalled. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
J Cogn Neurosci ; 30(10): 1532-1548, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29877766

RESUMEN

Visual working memory (VWM) is essential for executive function and is known to be compromised in older adults. Yet, the cognitive and neural processes associated with these age-related changes remain inconclusive. The purpose of this study was to explore such factors with a dynamic neural field (DNF) model that was manipulated to replicate the behavioral performances of younger and older adults in a change detection task. Although previous work has successfully modeled children and younger adult VWM performance, this study represents the first attempt to model older adult VWM performance within the DNF architecture. In the behavioral task, older adults performed worse than younger adults and exhibited a characteristic response bias that favored "same" over "different" responses. The DNF model was modified to capture the age group differences, with three parameter manipulations producing the best fit for the behavioral performances. The best-fitting model suggests that older adults operate through altered excitatory and inhibitory coupling and decreased inhibitory signals, resulting in wider and weaker neural signals. These results support a dedifferentiation account of brain aging, with older adults operating with wider and weaker neural signals because of decreased intracortical inhibition rather than increased stochastic neural noise.


Asunto(s)
Envejecimiento/fisiología , Encéfalo/fisiología , Memoria a Corto Plazo/fisiología , Modelos Neurológicos , Estimulación Luminosa/métodos , Percepción Visual/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología , Adulto Joven
11.
Prosthet Orthot Int ; 42(2): 144-152, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28351207

RESUMEN

BACKGROUND: Older adults with amputations secondary to vascular etiologies may additionally present with cognitive impairment. Cognition plays an important role in the adoption of a prosthetic limb, although the degree and type of impact are debated. Previous literature reviews have not been directed at the specific population of older adults who underwent vascular-related lower limb amputation. OBJECTIVES: First, to assess extant literature for relationships between cognitive function and prosthesis-related outcomes in older adults who underwent lower limb amputation for vascular-related etiologies. Second, to perform a critical analysis of prosthesis-related outcomes and cognitive assessments performed in the studies. STUDY DESIGN: Systematic literature review. METHODS: A systematic review of the literature was performed in databases using keyword combinations. A total of nine articles were selected to be included in this review. RESULTS: Seven of the nine included studies found a relationship between decreased cognitive function and reduced performance on a prosthesis-related outcome. There were eight different prosthesis-related outcome measures, with only one study utilizing a comprehensive outcome measure. CONCLUSION: Cognitive impairment can negatively impact successful prosthesis use in older adults with lower limb amputation secondary to vascular complications. Future studies should utilize comprehensive outcome measures that represent the multifaceted constructs of cognition and prosthesis use. Clinical relevance Cognitive assessment of older adults who have undergone lower limb amputation secondary to diabetes related complications or vascular disease can be used to inform clinical decision-making. Clinicians should consider selecting prosthesis-related outcome measures that capture the full breadth of prosthesis use when evaluating patients with cognitive impairment.


Asunto(s)
Amputados/psicología , Amputados/rehabilitación , Miembros Artificiales/estadística & datos numéricos , Disfunción Cognitiva/diagnóstico , Enfermedades Vasculares Periféricas/cirugía , Anciano , Amputación Quirúrgica/métodos , Miembros Artificiales/psicología , Disfunción Cognitiva/complicaciones , Femenino , Evaluación Geriátrica , Humanos , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/complicaciones , Enfermedades Vasculares Periféricas/diagnóstico , Pronóstico , Medición de Riesgo , Resultado del Tratamiento
12.
Front Psychol ; 8: 267, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28289397

RESUMEN

Embodied cognition is a theoretical framework which posits that cognitive function is intimately intertwined with the body and physical actions. Although the field of psychology is increasingly accepting embodied cognition as a viable theory, it has rarely been employed in the gerontological literature. However, embodied cognition would appear to have explanatory power for aging research given that older adults typically manifest concurrent physical and mental changes, and that research has indicated a correlative relationship between such changes. The current paper reviews age-related changes in sensory processing, mental representation, and the action-perception relationship, exploring how each can be understood through the lens of embodied cognition. Compared to younger adults, older adults exhibit across all three domains an increased tendency to favor visual processing over bodily factors, leading to the conclusion that older adults are less embodied than young adults. We explore the significance of this finding in light of existing theoretical models of aging and argue that embodied cognition can benefit gerontological research by identifying further factors that can explain the cause of age-related declines.

13.
Psychol Aging ; 30(3): 656-68, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26052886

RESUMEN

Theories of embodied perception hold that the visual system is calibrated by both the body schema and the action system, allowing for adaptive action-perception responses. One example of embodied perception involves the effects of tool use on distance perception, in which wielding a tool with the intention to act upon a target appears to bring that object closer. This tool-based spatial compression (i.e., tool-use effect) has been studied exclusively with younger adults, but it is unknown whether the phenomenon exists with older adults. In this study, we examined the effects of tool use on distance perception in younger and older adults in 2 experiments. In Experiment 1, younger and older adults estimated the distances of targets just beyond peripersonal space while either wielding a tool or pointing with the hand. Younger adults, but not older adults, estimated targets to be closer after reaching with a tool. In Experiment 2, younger and older adults estimated the distance to remote targets while using either a baton or a laser pointer. Younger adults displayed spatial compression with the laser pointer compared to the baton, although older adults did not. Taken together, these findings indicate a generalized absence of the tool-use effect in older adults during distance estimation, suggesting that the visuomotor system of older adults does not remap from peripersonal to extrapersonal spatial representations during tool use.


Asunto(s)
Envejecimiento/psicología , Percepción de Distancia/fisiología , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Adolescente , Anciano , Anciano de 80 o más Años , Imagen Corporal/psicología , Humanos , Rayos Láser , Adulto Joven
14.
Neuropsychopharmacology ; 39(8): 1843-51, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24513971

RESUMEN

Tobacco dependence is difficult to treat, with the vast majority of those who try to quit relapsing within the first year. Improvements in smoking cessation therapies may be achieved by improving current preclinical research methods. However, most experimental tests in animals use nicotine alone, ignoring the 8000 other constituents found in tobacco smoke. To improve on this model, we have used self-administration to test the reinforcing properties of aqueous cigarette smoke extract (CSE) in rats, made by bubbling cigarette smoke through a saline solution. CSE is more potent than nicotine alone in both the acquisition and maintenance of self-administration, but did not exhibit higher progressive ratio responding. Mecamylamine and varenicline had similar potencies to block nicotine and CSE self-administration, indicating the involvement of nicotinic receptors in CSE reinforcement. Following extinction of responding, reinstatement was triggered by exposing animals to a pharmacological stressor, yohimbine (2.5 mg/kg, i.p.), alone and in combination with cues. Animals that self-administered CSE were significantly more sensitive to stress-induced reinstatement than those that self-administered nicotine. Ligand binding autoradiography studies showed nicotine and CSE to have similar affinities for different nicotinic receptor types. CSE significantly reduced MAO-A and MAO-B activities in vitro, whereas nicotine did not. Although CSE inhibition of MAO-A activity in vitro was found to be partially irreversible, irreversible inhibition was not observed in vivo. These experiments show that CSE is an effective reinforcer acting via nicotinic receptors. Furthermore, it better models MAO inhibition and is more sensitive to stress-induced reinstatement than nicotine alone, which is a potent trigger for relapse in smokers.


Asunto(s)
Condicionamiento Operante/efectos de los fármacos , Nicotiana/química , Nicotina/farmacología , Receptores Nicotínicos/metabolismo , Refuerzo en Psicología , Humo , Animales , Masculino , Monoaminooxidasa/efectos de los fármacos , Monoaminooxidasa/metabolismo , Nicotina/administración & dosificación , Agonistas Nicotínicos/farmacología , Ratas , Ratas Sprague-Dawley
15.
Neuropsychopharmacology ; 37(6): 1367-76, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22278092

RESUMEN

Genomic and pharmacologic data have suggested the involvement of the α3ß4 subtype of nicotinic acetylcholine receptors (nAChRs) in drug seeking to nicotine and other drugs of abuse. In order to better examine this receptor subtype, we have identified and characterized the first high affinity and selective α3ß4 nAChR antagonist, AT-1001, both in vitro and in vivo. This is the first reported compound with a Ki below 10 nM at α3ß4 nAChR and >90-fold selectivity over the other major subtypes, the α4ß2 and α7 nAChR. AT-1001 competes with epibatidine, allowing for [³H]epibatidine binding to be used for structure-activity studies, however, both receptor binding and ligand-induced Ca²âº flux are not strictly competitive because increasing ligand concentration produces an apparent decrease in receptor number and maximal Ca²âº fluorescence. AT-1001 also potently and reversibly blocks epibatidine-induced inward currents in HEK cells transfected with α3ß4 nAChR. Importantly, AT-1001 potently and dose-dependently blocks nicotine self-administration in rats, without affecting food responding. When tested in a nucleus accumbens (NAcs) synaptosomal preparation, AT-1001 inhibits nicotine-induced [³H]dopamine release poorly and at significantly higher concentrations compared with mecamylamine and conotoxin MII. These results suggest that its inhibition of nicotine self-administration in rats is not directly due to a decrease in dopamine release from the NAc, and most likely involves an indirect pathway requiring α3ß4 nAChR. In conclusion, our studies provide further evidence for the involvement of α3ß4 nAChR in nicotine self-administration. These findings suggest the utility of this receptor as a target for smoking cessation medications, and highlight the potential of AT-1001 and congeners as clinically useful compounds.


Asunto(s)
Condicionamiento Operante/efectos de los fármacos , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Antagonistas Nicotínicos/farmacología , Oligopéptidos/farmacología , Análisis de Varianza , Animales , Biofisica , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacocinética , Calcio/metabolismo , Línea Celular Transformada , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Alimentos , Humanos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/genética , Antagonistas Nicotínicos/química , Núcleo Accumbens/efectos de los fármacos , Oligopéptidos/química , Técnicas de Placa-Clamp , Unión Proteica/efectos de los fármacos , Piridinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Autoadministración , Transfección , Tritio/metabolismo , Tritio/farmacocinética
16.
Arch Gen Psychiatry ; 68(9): 953-60, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21536968

RESUMEN

CONTEXT: Despite progress in tobacco control, secondhand smoke (SHS) exposure remains prevalent worldwide and is implicated in the initiation and maintenance of cigarette smoking. OBJECTIVE: To determine whether moderate SHS exposure results in brain α(4)ß(2)* nicotinic acetylcholine receptor (nAChR) occupancy. DESIGN, SETTING, AND PARTICIPANTS: Positron emission tomography scanning and the radiotracer 2-[18F]fluoro-3-(2(S)azetidinylmethoxy) pyridine (also known as 2-[(18)F]fluoro-A-85380, or 2-FA) were used to determine α(4)ß(2)* nAChR occupancy from SHS exposure in 24 young adult participants (11 moderately dependent cigarette smokers and 13 nonsmokers). Participants underwent two bolus-plus-continuous-infusion 2-FA positron emission tomography scanning sessions during which they sat in the passenger's seat of a car for 1 hour and either were exposed to moderate SHS or had no SHS exposure. The study took place at an academic positron emission tomography center. Main Outcome Measure  Changes induced by SHS in 2-FA specific binding volume of distribution as a measure of α(4)ß(2)* nAChR occupancy. RESULTS: An overall multivariate analysis of variance using specific binding volume of distribution values revealed a significant main effect of condition (SHS vs control) (F(1,22) = 42.5, P < .001) but no between-group (smoker vs nonsmoker) effect. Exposure to SHS led to a mean 19% occupancy of brain α(4)ß(2)* nAChRs (1-sample t test, 2-tailed, P < .001). Smokers had both a mean 23% increase in craving with SHS exposure and a correlation between thalamic α(4)ß(2)* nAChR occupancy and craving alleviation with subsequent cigarette smoking (Spearman ρ = -0.74, P = .01). CONCLUSIONS: Nicotine from SHS exposure results in substantial brain α(4)ß(2)* nAChR occupancy in smokers and nonsmokers. Study findings suggest that such exposure delivers a priming dose of nicotine to the brain that contributes to continued cigarette use in smokers. This study has implications for both biological research into the link between SHS exposure and cigarette use and public policy regarding the need to limit SHS exposure in cars and other enclosed spaces.


Asunto(s)
Encéfalo/metabolismo , Agonistas Nicotínicos , Receptores Nicotínicos/metabolismo , Contaminación por Humo de Tabaco/efectos adversos , Adulto , Azetidinas , Conducta Adictiva/metabolismo , Femenino , Radioisótopos de Flúor , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Tomografía de Emisión de Positrones/métodos , Ensayo de Unión Radioligante
17.
Arch Gen Psychiatry ; 68(5): 505-15, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21199957

RESUMEN

CONTEXT: Nicotine-dependent smokers exhibit craving and brain activation in the prefrontal and limbic regions when presented with cigarette-related cues. Bupropion hydrochloride treatment reduces cue-induced craving in cigarette smokers; however, the mechanism by which bupropion exerts this effect has not yet been described. OBJECTIVE: To assess changes in regional brain activation in response to cigarette-related cues from before to after treatment with bupropion (vs placebo). DESIGN: Randomized, double-blind, before-after controlled trial. SETTING: Academic brain imaging center. PARTICIPANTS: Thirty nicotine-dependent smokers (paid volunteers). INTERVENTIONS: Participants were randomly assigned to receive 8 weeks of treatment with either bupropion or a matching placebo pill (double-blind). MAIN OUTCOME MEASURES: Subjective cigarette craving ratings and regional brain activations (blood oxygen level-dependent response) in response to viewing cue videos. RESULTS: Bupropion-treated participants reported less craving and exhibited reduced activation in the left ventral striatum, right medial orbitofrontal cortex, and bilateral anterior cingulate cortex from before to after treatment when actively resisting craving compared with placebo-treated participants. When resisting craving, reduction in self-reported craving correlated with reduced regional brain activation in the bilateral medial orbitofrontal and left anterior cingulate cortices in all participants. CONCLUSIONS: Treatment with bupropion is associated with improved ability to resist cue-induced craving and a reduction in cue-induced activation of limbic and prefrontal brain regions, while a reduction in craving, regardless of treatment type, is associated with reduced activation in prefrontal brain regions.


Asunto(s)
Antidepresivos de Segunda Generación/uso terapéutico , Bupropión/uso terapéutico , Señales (Psicología) , Procesamiento de Imagen Asistido por Computador , Sistema Límbico/efectos de los fármacos , Sistema Límbico/fisiopatología , Imagen por Resonancia Magnética , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiopatología , Cese del Hábito de Fumar/psicología , Fumar/fisiopatología , Tabaquismo/fisiopatología , Adulto , Mapeo Encefálico , Dominancia Cerebral/fisiología , Método Doble Ciego , Femenino , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/fisiopatología , Giro del Cíngulo/efectos de los fármacos , Giro del Cíngulo/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Motivación/efectos de los fármacos , Motivación/fisiología , Fumar/tratamiento farmacológico , Fumar/psicología , Lóbulo Temporal/efectos de los fármacos , Lóbulo Temporal/fisiopatología , Tabaquismo/psicología , Tabaquismo/rehabilitación
18.
Psychiatry Res ; 183(3): 218-24, 2010 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-20682457

RESUMEN

The aim of this study was to determine whether standard treatments for Tobacco Dependence affect smoking-induced changes in intrasynaptic dopamine (DA) concentration. Forty-three otherwise healthy adult cigarette smokers (10 to 40 cigarettes per day) were treated with either practical group counseling (PGC) psychotherapy (n=14), bupropion HCl (n=14), or matching pill placebo (n=15) (random assignment) for 8 weeks. Before and after treatment, each subject underwent a bolus-plus-continuous-infusion (11)C-raclopride positron emission tomography (PET) scanning session, during which he or she smoked a regular cigarette. The PET scanning outcome measure of interest was percent change in smoking-induced (11)C-raclopride binding potential (BP(ND)) in the ventral caudate/nucleus accumbens (VCD/NAc), as an indirect measure of DA release. Although the entire study sample had a smaller mean smoking-induced reduction in VCD/NAc BP(ND) after treatment (compared to before treatment), this change was highly correlated with smaller total cigarette puff volumes (and not other treatment variables). These data indicate that smoking-induced DA release is dose-dependent, and is not significantly affected by reductions in daily smoking levels or treatment type.


Asunto(s)
Bupropión/uso terapéutico , Inhibidores de Captación de Dopamina/uso terapéutico , Dopamina/metabolismo , Fumar/metabolismo , Sinapsis/metabolismo , Tabaquismo/tratamiento farmacológico , Adulto , Anciano , Análisis de Varianza , Antagonistas de Dopamina/farmacocinética , Método Doble Ciego , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Racloprida/farmacocinética , Fumar/psicología , Estadística como Asunto , Sinapsis/diagnóstico por imagen , Tabaquismo/diagnóstico por imagen , Adulto Joven
19.
Psychol Aging ; 25(2): 356-68, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20545420

RESUMEN

Previous research has suggested that an age-related decline in change detection may be due to older adults using a more conservative response criterion. However, this finding may reflect methodological limitations of the traditional change detection design, in which displays are presented continuously until a change is detected. Across 2 experiments, the authors assessed adult age differences in a version of change detection that required a response after each pair of pre- and postchange displays, thus reducing the potential contribution of response criterion. Older adults performed worse than younger adults, committing more errors and requiring a greater number of display cycles for correct detection. These age-related performance declines were substantially reduced after controlling statistically for elementary perceptual speed. Search strategy was largely similar for the 2 age groups, but perceptual speed was less successful in accounting for age-related variance in detectability when a more precise spatial localization of change was required (Experiment 2). Thus, the negative effect of aging in the present tasks lies in a reduction of detection efficiency due largely to processing speed, though some strategy-level effects may also contribute. (PsycINFO Database Record (c) 2010 APA, all rights reserved).


Asunto(s)
Envejecimiento/psicología , Atención , Discriminación en Psicología , Reconocimiento Visual de Modelos , Adolescente , Adulto , Anciano , Conducta de Elección , Femenino , Humanos , Juicio , Masculino , Persona de Mediana Edad , Desempeño Psicomotor , Tiempo de Reacción , Adulto Joven
20.
Exp Aging Res ; 36(3): 249-72, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20544447

RESUMEN

Visual search studies have demonstrated that older adults can have preserved or even increased top-down control over distraction. However, the results are mixed as to the extent of this age-related preservation. The present experiment assesses group differences in younger and older adults during visual search, with a task featuring two conditions offering varying degrees of top-down control over distraction. After controlling for generalized slowing, the analyses revealed that the age groups were equally capable of utilizing top-down control to minimize distraction. Furthermore, for both age groups, the distraction effect was manifested in a sustained manner across the reaction time distribution.


Asunto(s)
Envejecimiento/psicología , Percepción Visual/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Visión de Colores , Femenino , Humanos , Pruebas de Inteligencia , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Agudeza Visual , Adulto Joven
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