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1.
Musculoskelet Sci Pract ; 72: 102948, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38588610

RESUMO

BACKGROUND: Although footwear can improve pain and function in individuals with knee osteoarthritis (OA), perspectives about footwear in this population have not been explored. OBJECTIVES: This qualitative study explored preferences, attitudes and beliefs about footwear in adults with knee OA. METHODS: Twenty individuals with a clinical diagnosis of knee OA (aged 45-79 years, 65% women) participated in semi-structured interviews about factors which influence footwear selection, the effect of footwear on knee symptoms, and footwear modifications. Data were analysed thematically. RESULTS: Four themes, with sub-themes, were identified: i) there are specific footwear characteristics people look for, with comfort as their top priority; ii) shoe appearance is important; iii) footwear can aggravate or ease symptoms; and iv) people with knee OA find footwear in a variety of ways. Participants related built-in arch support, a cushioned insole and low/no heel, without addition of foot orthoses, to comfort, and were willing to pay more for comfort and quality. Appearance was also a consideration, and participants indicated they would tolerate short periods of symptom aggravation for aesthetic shoes. Participants felt that footwear choice affected their knee symptoms and risk of slipping/twisting. Participants reported that their footwear choices were determined through trial-and-error, and sometimes on advice from health professionals or shoe store salespersons. CONCLUSIONS: There are specific footwear features important to individuals with knee OA. Knowledge of these features can be used by health professionals to inform footwear discussions with knee OA patients and serve as considerations when developing footwear targeted for this population.

2.
Psychol Serv ; 19(2): 386-395, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33844563

RESUMO

The prevalence of co-occurring posttraumatic stress disorder (PTSD) and substance use disorder (SUD) remains exceptionally high among returning veterans, with numerous studies linking PTSD, but not specific PTSD symptoms, to future SUD risk. Further explication of PTSD symptom effects on future SUD risk will likely promote intervention development and refinement while offsetting SUD risk. Accordingly, In this study we explored the prospective associations between PTSD symptom clusters, symptoms, and future SUD risk and use of specific drug classes. Returning veterans (N = 1,295; Mage = 42.3, SD = 9.89; 51% female; 66.8% White) completed structured diagnostic interviews to assess PTSD symptoms and self-report measures of substance use 14-36 months later (M = 24.59, SD = 2.97). Hyperarousal and reckless/self-destructive symptoms specifically predicted future high-risk drug use and binge drinking behavior, and avoidance of internal stimuli (i.e., of trauma memories, thoughts, and feelings) differentiated individuals classified as high-risk for alcohol use based on their AUDIT total score. Further, negative alterations in cognition and mood predicted future opioid (i.e., nightmares) and stimulant use (i.e., flashbacks), whereas concentration difficulties were inversely associated with future binge drinking. This longitudinal study identified prospective and enduring associations between specific PTSD symptom clusters, symptoms, and future high-risk substance use patterns among returning veterans. Accordingly, careful assessment of specific PTSD criteria and differential motivations for substance use is warranted, along with tailored interventions to offset risk for opioid, stimulant, and alcohol use among returning veterans. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Transtornos de Estresse Pós-Traumáticos , Transtornos Relacionados ao Uso de Substâncias , Veteranos , Adulto , Analgésicos Opioides , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Síndrome
3.
Psychol Addict Behav ; 36(2): 131-143, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34351175

RESUMO

OBJECTIVE: Cannabis use disorder (CUD) is the most common non-alcohol related substance use disorder (SUD) in the United States and is especially prevalent among returning veterans. The long-term mental health correlates of CUD remain unknown, which is significant given the rise in legalization and also recreational and medicinal cannabis use nationally. METHOD: Using a gender-balanced, national sample of 1,649 veterans (n = 115 with CUD; 75.2% White; M age = 37.49, SD = 9.88), we used latent growth curve modeling to examine posttraumatic stress disorder (PTSD) symptom severity, depressive symptoms, generalized anxiety, alcohol use, and psychosocial functioning between veterans with versus without a prior diagnosis of CUD over five time points, spanning an average of 7 years. RESULTS: Returning veterans with CUD compared to those without reported higher alcohol use, depression, anxiety, PTSD symptom severity, and worse psychosocial functioning at baseline. We observed nonlinear change across each outcome. We also found that CUD moderated change in alcohol use (quadratic: b = -.129, p < .001) and PTSD symptoms (quadratic: b = -.280, p = .019), such that individuals with CUD evidenced decelerated change and worse outcomes relative to veterans without a previously documented CUD diagnosis. Trajectories of depression, anxiety, and psychosocial functioning were similar across individuals with versus without CUD. CONCLUSIONS: In the first long-term and longitudinal evaluation of mental health and alcohol use course among returning veterans, CUD was associated with worse and more persistent alcohol use and PTSD symptom severity over time. These data have implications for clinical assessment, case conceptualization, and treatment of veterans and may inform efforts to offset risk for hazardous drinking and PTSD following a diagnosis of CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Cannabis , Abuso de Maconha , Transtornos de Estresse Pós-Traumáticos , Transtornos Relacionados ao Uso de Substâncias , Veteranos , Adulto , Comorbidade , Humanos , Abuso de Maconha/epidemiologia , Saúde Mental , Transtornos de Estresse Pós-Traumáticos/psicologia , Estados Unidos/epidemiologia , Veteranos/psicologia
4.
Addict Behav ; 118: 106870, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33667852

RESUMO

OBJECTIVES: Posttraumatic stress disorder (PTSD) and substance use share both directional ("self-medication") and mutually-reinforcing associations over time. Research on gender differences regarding the co-occurrence of PTSD and substance use over time remains limited and largely focused on alcohol use; less is known regarding the co-occurrence of PTSD and illicit drug use, especially among veteran men vs. women. As the proportion of women in the military expands, we believe a greater focus on gender differences is warranted. METHOD: We conducted a cross-lagged panel analysis of PTSD symptoms and drug use problems using two waves of data from a large, nationwide longitudinal registry of post-9/11 veterans. Participants included 608 men and 635 women (N = 1243; Mage = 42.3; 75.2% White) who completed self-report PTSD and drug use problem questionnaires at T1 and again at T2 15-37 months later. RESULTS: Veteran men reported more severe drug use and related problems overall, yet the cross-sectional correlation between PTSD and drug use problems was strongest among drug using veteran women. In our cross-lagged models, we found that PTSD symptoms predicted future drug use problems among veteran men, whereas drug use problems predicted future PTSD symptom severity among women. CONCLUSIONS: These results support the self-medication pathway among veteran men but not women, for whom drug use problems might prolong or exacerbate PTSD symptom severity over time. These results are consistent with some emerging evidence but also provide novel insight into functional associations governing the longitudinal course of PTSD and drug use problems for men vs. women.


Assuntos
Drogas Ilícitas , Transtornos de Estresse Pós-Traumáticos , Transtornos Relacionados ao Uso de Substâncias , Veteranos , Adulto , Campanha Afegã de 2001- , Estudos Transversais , Feminino , Humanos , Guerra do Iraque 2003-2011 , Masculino , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
5.
J Psychoactive Drugs ; 51(5): 413-420, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31352867

RESUMO

Cannabis remains the most frequently used illicit drug in the United States. As its legal status has changed, more people have turned to oral administration ("edibles"). 172 individuals who reported an uncomfortable experience with edible cannabis completed an online survey. Despite the aversive nature of the experience, 62.9% of the sample reported that the edible experience was at least somewhat meaningful and the majority of participants (95.2%) did not report any medical problems. The most common non-medical problem reported was going to bed early or lying down (75.8%). Most participants (69.2%) reported that dose was the key contributor to their negative experience. Participants who rated the experience as more aversive were less likely to use edibles again, r (167) = - .180, p < . 05. In addition, the duration of the aversive experience correlated positively with aversiveness rating, r (167) = . 244, p < . 05. With increased legalization of cannabis, edible use may rise. Dose seems to be associated with uncomfortable experiences with edible cannabis. Notwithstanding these uncomfortable experiences, the vast majority of the sample used cannabis edibles again, reported that the experience was at least somewhat meaningful, and did not report significant problems associated with the experience.


Assuntos
Cannabis/efeitos adversos , Comportamento do Consumidor/estatística & dados numéricos , Alimentos/efeitos adversos , Uso da Maconha/efeitos adversos , Adulto , Humanos
6.
J Psychoactive Drugs ; 50(5): 411-419, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30183528

RESUMO

Impulsivity and substance use covary. Smith and Anderson's acquired preparedness model proposes that impulsivity predicts substance use through a mediational model such that substance use expectancies mediate the relation between impulsivity and drug use. The present study seeks to examine the relation between positive urgency, an important component of impulsivity with specific relations to substance use behavior, marijuana expectancies, and marijuana use patterns. The study focused on a sample of frequent marijuana users (n = 3,616) and assessed positive urgency using the UPPS-P, expectancies using the Biphasic Marijuana Effects Scale, an adapted form of the Biphasic Alcohol Effects Scale to measure the sedative and stimulant properties of marijuana, and also assessed use patterns. Findings suggest that stimulant expectancies predict heavier, more frequent marijuana use than sedative expectancies and that marijuana expectancies vary based on the limb of marijuana intoxication. Examination of the acquired preparedness model revealed that positive urgency's link to marijuana use was fully mediated by expectancies.


Assuntos
Comportamento Impulsivo , Uso da Maconha/epidemiologia , Modelos Psicológicos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Feminino , Humanos , Masculino , Uso da Maconha/psicologia , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/psicologia
7.
J Psychoactive Drugs ; 50(4): 348-354, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29714640

RESUMO

Medical cannabis research has become quite extensive, with indications ranging from glaucoma to chemotherapy-induced nausea. Despite increased interest in cannabis' potential medical uses, research barriers, cannabis legislation, stigma, and lack of dissemination of data contribute to low adoption for some medical populations. Of interest, cannabis use appears low in palliative care settings, with few guidelines available to palliative care providers. The present study sought to examine the attitudes, beliefs, and practices of palliative care providers regarding the use of cannabis for terminally ill patients. Palliative care providers (N = 426) completed a one-time online survey assessing these attitudes, beliefs, and practices. Results demonstrated that palliative care providers endorse cannabis for a wide range of palliative care symptoms, end-of-life care generally, and as an adjuvant medication. Nevertheless, the gap between these beliefs and actual recommendation or prescription appears vast. Many who support the use of cannabis in palliative care do not recommend it as a treatment. These data suggest recommendations for healthcare providers and palliative care organizations.


Assuntos
Pessoal de Saúde/estatística & dados numéricos , Maconha Medicinal/uso terapêutico , Cuidados Paliativos/métodos , Assistência Terminal/métodos , Adulto , Atitude do Pessoal de Saúde , Feminino , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade
8.
Brain Res ; 1687: 173-184, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29524436

RESUMO

Adolescence is a period during which a number of critical neuromaturation processes occur and the vulnerability for developing nicotine dependence is extremely high. Thus, early-onset (EO; age < 16 years old), relative to late-onset (LO; age ≥ 16 years old), tobacco smoking may be uniquely deleterious for developmentally immature systems that regulate neural signaling reactivity. This study investigated how age of tobacco smoking onset affects neurophysiological measures of smoking cue reactivity and reported craving in adult smokers. EO smokers (EOS; n = 8; 4 females), LO smokers (LOS; n = 10; 5 females), and healthy non-smokers (HNS; n = 10; 5 females) participated in an event-related potential (ERP) cue reactivity study with tactile and image stimuli. Participants handled neutral objects during one interval and smoking-related objects during a second interval. After each interval, they viewed smoking-related, neutral, or arousing images using an oddball paradigm. P300 ERPs and craving for tobacco were recorded during each session. P300 amplitudes were significantly higher in central midline (Cz) channel to smoking, but not neutral or arousing, images after handling smoking objects. Specifically, Cz P300 smoking amplitudes were significantly greater in EOS, relative to LOS and HNS, and associated with greater craving at baseline. There were no other group differences in mood or craving. EOS exhibited greater P300 reactivity to smoking-related stimuli, relative to LOS, suggesting a more sensitized neural response. EO smoking during early neuromaturation may alter neurophysiological signaling involved in responding to smoking-related stimuli, which could impact the outcome of smoking cessation interventions.


Assuntos
Fumar Cigarros/fisiopatologia , Fumar Cigarros/psicologia , Fissura/fisiologia , Potenciais Evocados P300/fisiologia , Fumantes/psicologia , Adulto , Idade de Início , Análise de Variância , Nível de Alerta/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Transtornos do Humor/etiologia , Tempo de Reação/fisiologia , Índice de Gravidade de Doença , Tabagismo/fisiopatologia , Tabagismo/psicologia
9.
Drug Alcohol Depend ; 184: 48-56, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29402679

RESUMO

BACKGROUND: Initiation of cigarette smoking during adolescence coincides with structural and cognitive neuromaturation. Thus, early onset smokers (EOS; initiated <16 years old) may be at unique risk of altered development of executive function relative to late onset smokers (LOS; initiated >16 years old). This study quantified the effects of age of smoking onset on response impulsivity and inhibitory control using a novel smoking Go/NoGo task (Luijten et al., 2011). METHODS: Nicotine deprived adult EOS (n = 10) and LOS (n = 10) and adult healthy non-smokers (HNS; n = 10) were shown smoking-related and neutral images with either a blue (Go) or yellow (NoGo) frame. Participants were instructed to respond to blue-framed Go trials quickly and accurately, and withhold responding for yellow-framed NoGo trials. RESULTS: EOS made more Go response accuracy errors (p ≤ 0.02) and failed more frequently to inhibit responses to NoGo trials (p < 0.02) than LOS and HNS. EOS also made more errors in inhibiting responses to smoking-related (p ≤ 0.02) and neutral (p ≤ 0.02) NoGo trials. EOS reported greater baseline craving for cigarette smoking than LOS (p < 0.04), and craving was significantly associated with greater omission errors (p ≤ 0.04). CONCLUSIONS: EOS exhibited greater difficulty than LOS in responding accurately to Go stimuli and withholding responses to both smoking and neutral NoGo stimuli, indicating greater response impulsivity, poor attention, and deficits in response inhibition. These findings suggest that EO smoking, in particular, contributes to diminished task-related attention and inhibitory control behaviors in adulthood and provide support for the tobacco-induced neurotoxicity of adolescent cognitive development (TINACD) theory (DeBry and Tiffany, 2008).


Assuntos
Atenção/fisiologia , Comportamento Impulsivo/fisiologia , Inibição Psicológica , Fumantes/psicologia , Fumar/psicologia , Adulto , Fatores Etários , Cognição/fisiologia , Fissura/fisiologia , Eletroencefalografia/métodos , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
10.
J Psychoactive Drugs ; 49(5): 393-397, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28771093

RESUMO

Previous research has demonstrated the ability of non-active smoked cannabis cigarettes to induce subjective effects of intoxication (i.e., placebo effect). No studies have been conduced to test whether edible forms of cannabis, which are associated with a significant delay in onset of effect, are able to induce a placebo effect. In the present study, 20 participants were told that they would receive an edible cannabis lollipop containing a high dose of tetrahydrocannabinol (THC), but were instead given a placebo control. Measures of intoxication and mood were taken at baseline, 30 minutes, and 60 minutes post-ingestion of the placebo lollipop. Results of four repeated-measures ANOVAs found significant and quadratic changes across time in cannabis (ARCI m-scale) intoxication (F(2,18) = 4.90, p = .01, η2 = .22) and negative mood (F(2,18) = 3.99, p = .05, η2 = .19). Changes in positive mood and the overall measure of general intoxication (ARCI) failed to reach significance. The present study provides preliminary evidence that a placebo effect can be induced with inert edible agents when participants are told that they are receiving active THC. This is the first known study to demonstrate an edible cannabis intoxication placebo effect.


Assuntos
Afeto , Dronabinol/administração & dosagem , Alucinógenos/administração & dosagem , Efeito Placebo , Administração Oral , Análise de Variância , Feminino , Humanos , Masculino , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
11.
Drug Alcohol Depend ; 178: 469-476, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28711813

RESUMO

BACKGROUND: Biological sex influences cigarette smoking behavior. More men than women smoke, but women have a harder time quitting. Sex differences in smoking cue (SC) reactivity may underlie such behavioral differences. However, the influence of sex on brain reactivity to SCs has yielded inconsistent findings suggesting the need for continued study. Here, we investigated the effect of sex on SC reactivity across two sites using different imaging modalities and SC stimulus types. METHODS: Pseudo-continuous arterial spin-labeled (pCASL) perfusion functional magnetic resonance imaging (fMRI) was used to assess brain responses to SC versus non-SC videos in 40 smokers (23 females) at the University of Pennsylvania. BOLD fMRI was used to assess brain responses to SC versus non-SC still images in 32 smokers (18 females) at McLean Hospital. Brain reactivity to SCs was compared between men and women and was correlated with SC-induced craving. RESULTS: In both cohorts, males showed higher SC versus non-SC reactivity compared to females in reward-related brain regions (i.e., ventral striatum/ventral pallidum, ventral medial prefrontal cortex). Brain activation during SC versus non-SC exposure correlated positively with SC-induced subjective craving in males, but not females. CONCLUSIONS: The current work provides much needed replication and validation of sex differences in SC-reactivity. These findings also add to a body of literature showing that men have greater reward-related brain activation to drug cues across drug classes. Such sex differences confirm the need to consider sex not only when evaluating SC-reactivity but when examining nicotine dependence etiology and treatment.


Assuntos
Encéfalo/fisiopatologia , Sinais (Psicologia) , Imageamento por Ressonância Magnética/métodos , Fumar/fisiopatologia , Fumar Tabaco/fisiopatologia , Tabagismo/fisiopatologia , Condicionamento Psicológico/fisiologia , Consenso , Fissura , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Caracteres Sexuais
12.
Behav Res Methods ; 49(1): 74-82, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26896241

RESUMO

We describe a low-cost, MRI-compatible olfactometer that delivers fresh cigarette smoke odor, a challenging odorant to present, as well as other odorants. This new olfactometer retains all of the advantages of an earlier design that was capable of only delivering volatile odors (Lowen & Lukas, Behavior Research Methods, 38, 307-313, 2006). The new system incorporates a novel switching mechanism that allows it to deliver fresh smoke generated from a burning cigarette during a stimulus presentation paradigm that might be employed in a cue-reactivity experiment. An evaluation study established that the olfactometer reliably delivered smoke to the participants and that tobacco smoke was discriminated from other odorants; there were no adverse reactions to the device.


Assuntos
Imageamento por Ressonância Magnética/métodos , Nicotiana , Olfatometria/instrumentação , Fumaça , Administração por Inalação , Adulto , Discriminação Psicológica , Feminino , Humanos , Masculino , Odorantes , Olfatometria/economia , Adulto Jovem
13.
Drug Alcohol Depend ; 155: 202-7, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26233484

RESUMO

BACKGROUND: Dysfunctional reward processing leading to the undervaluation of non-drug rewards is hypothesized to play a crucial role in nicotine dependence. However, it is unclear if blunted reward responsivity and the desire to use nicotine are directly linked after a brief period of abstinence. Such an association would suggest that individuals with reduced reward responsivity may be at increased risk to experience nicotine craving. METHODS: Reward function was evaluated with a probabilistic reward task (PRT), which measures reward responsivity to monetary incentives. To identify whether smoking status influenced reward function, PRT performance was compared between non-depressed, nicotine-dependent smokers and non-smokers. Within smokers, correlations were conducted to determine if blunted reward responsivity on the PRT was associated with increased nicotine craving. Time since last nicotine exposure was standardized to 4h for all smokers. RESULTS: Smokers and non-smokers did not differ in reward responsivity on the PRT. However, within smokers, a significant negative correlation was found between reward responsivity and intensity of nicotine craving. CONCLUSIONS: The current findings show that, among smokers, the intensity of nicotine craving is linked to lower sensitivity to non-drug rewards. This finding is in line with prior theories that suggest reward dysfunction in some clinical populations (e.g., depressive disorders, schizophrenia) may facilitate nicotine use. The current study expands on such theories by indicating that sub-clinical variations in reward function are related to motivation for nicotine use. Identifying smokers who show blunted sensitivity to non-drug rewards may help guide treatments aimed at mitigating the motivation to smoke.


Assuntos
Fissura , Recompensa , Tabagismo/psicologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino
14.
Neuropsychopharmacology ; 40(7): 1561-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25567427

RESUMO

The insula plays a critical role in maintaining nicotine dependence and reactivity to smoking cues. More broadly, the insula and the dorsal anterior cingulate cortex (dACC) are key nodes of the salience network (SN), which integrates internal and extrapersonal information to guide behavior. Thus, insula-dACC interactions may be integral in processing salient information such as smoking cues that facilitate continued nicotine use. We evaluated functional magnetic resonance imaging (fMRI) data from nicotine-dependent participants during rest, and again when they viewed smoking-related images. Greater insula-dACC coupling at rest was significantly correlated with enhanced smoking cue-reactivity in brain areas associated with attention and motor preparation, including the visual cortex, right ventral lateral prefrontal cortex, and the dorsal striatum. In an independent cohort, we found that insula-dACC connectivity was stable over 1-h delay and was not influenced by changes in subjective craving or expired carbon monoxide, suggesting that connectivity strength between these regions may be a trait associated with heightened cue-reactivity. Finally, we also showed that insula reactivity to smoking cues correlates with a rise in cue-reactivity throughout the entire SN, indicating that the insula's role in smoking cue-reactivity is not functionally independent, and may actually represent the engagement of the entire SN. Collectively, these data provide a more network-level understanding of the insula's role in nicotine dependence and shows a relationship between inherent brain organization and smoking cue-reactivity.


Assuntos
Córtex Cerebral/fisiologia , Sinais (Psicologia) , Giro do Cíngulo/fisiologia , Vias Neurais/fisiologia , Fumar/patologia , Adulto , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Feminino , Giro do Cíngulo/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/irrigação sanguínea , Oxigênio/sangue , Estimulação Luminosa , Inquéritos e Questionários , Adulto Jovem
15.
Neuropsychopharmacology ; 40(2): 406-11, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25056595

RESUMO

The striatum has a clear role in addictive disorders and is involved in drug-related craving. Recently, enhanced striatal volume was associated with greater lifetime nicotine exposure, suggesting a bridge between striatal function and structural phenotypes. To assess this link between striatal structure and function, we evaluated the relationship between striatal morphology and this brain region's well-established role in craving. In tobacco smokers, we assessed striatal volume, surface area, and shape using a new segmentation methodology coupled with local shape indices. Striatal morphology was then related with two measures of craving: state-based craving, assessed by the brief questionnaire of smoking urges (QSU), and craving induced by smoking-related images. A positive association was found between left striatal volume and surface area with both measures of craving. A more specific relationship was found between both craving measures and the dorsal, but not in ventral striatum. Evaluating dorsal striatal subregions showed a single relationship between the caudate and QSU. Although cue-induced craving and the QSU were both associated with enlarged striatal volume and surface area, these measures were differentially associated with global or more local striatal volumes. We also report a connection between greater right striatal shape deformations and cue-induced craving. Shape deformations associated with cue-induced craving were specific to striatal subregions involved in habitual responding to rewarding stimuli, which is relevant given the habitual nature of cue-induced craving. The current findings confirm a relationship between striatal function and morphology and suggest that variation in striatal morphology may be a biomarker for craving severity.


Assuntos
Corpo Estriado/patologia , Fissura , Fumar/patologia , Tabagismo/patologia , Adulto , Sinais (Psicologia) , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Índice de Gravidade de Doença
16.
Addict Biol ; 20(2): 349-56, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24261848

RESUMO

Nicotine dependence is a chronic and difficult to treat disorder. While environmental stimuli associated with smoking precipitate craving and relapse, it is unknown whether smoking cues are cognitively processed differently than neutral stimuli. To evaluate working memory differences between smoking-related and neutral stimuli, we conducted a delay-match-to-sample (DMS) task concurrently with functional magnetic resonance imaging (fMRI) in nicotine-dependent participants. The DMS task evaluates brain activation during the encoding, maintenance and retrieval phases of working memory. Smoking images induced significantly more subjective craving, and greater midline cortical activation during encoding in comparison to neutral stimuli that were similar in content yet lacked a smoking component. The insula, which is involved in maintaining nicotine dependence, was active during the successful retrieval of previously viewed smoking versus neutral images. In contrast, neutral images required more prefrontal cortex-mediated active maintenance during the maintenance period. These findings indicate that distinct brain regions are involved in the different phases of working memory for smoking-related versus neutral images. Importantly, the results implicate the insula in the retrieval of smoking-related stimuli, which is relevant given the insula's emerging role in addiction.


Assuntos
Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiologia , Fumar/psicologia , Tabagismo/psicologia , Adolescente , Adulto , Córtex Cerebral/fisiologia , Fissura , Sinais (Psicologia) , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Estimulação Luminosa , Adulto Jovem
17.
PLoS One ; 9(2): e88228, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24505440

RESUMO

Craving is a key aspect of drug dependence that is thought to motivate continued drug use. Numerous brain regions have been associated with craving, suggesting that craving is mediated by a distributed brain network. Whether an increase in subjective craving is associated with enhanced interactions among brain regions was evaluated using resting state functional magnetic imaging (fMRI) in nicotine dependent participants. We focused on craving-related changes in the orbital and medial prefrontal cortex (OMPFC) network, which also included the subgenual anterior cingulate cortex (sgACC) extending into the ventral striatum. Brain regions in the OMPFC network are not only implicated in addiction and reward, but, due to their rich anatomic interconnections, may serve as the site of integration across craving-related brain regions. Subjective craving and resting state fMRI were evaluated twice with an ∼1 hour delay between the scans. Cigarette craving was significantly increased at the end, relative to the beginning of the scan session. Enhanced craving was associated with heightened coupling between the OMPFC network and other cortical, limbic, striatal, and visceromotor brain regions that are both anatomically interconnected with the OMPFC, and have been implicated in addiction and craving. This is the first demonstration confirming that an increase in craving is associated with enhanced brain region interactions, which may play a role in the experience of craving.


Assuntos
Córtex Pré-Frontal/fisiopatologia , Tabagismo/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Nicotiana/efeitos adversos , Adulto Jovem
18.
Neuropsychopharmacology ; 38(6): 1113-20, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23306182

RESUMO

Substance abusers have difficulty ignoring drug-related cues, which is associated with relapse vulnerability. This 'attentional bias' towards drug cues translates into an inability to ignore drug-related stimuli and may reflect deficits in the brain regions, such as the dorsal anterior cingulate cortex (dACC)-a key region in cognitive control and adaptive decision making. Quantifying relationships between attentional biases to drug cues and dACC neurochemistry could aid in identifying neurobiological mechanisms associated with increased relapse vulnerability precipitated by drug cues. As gamma-aminobutyric acid (GABA) deficits have been linked to impaired cognition and addictive disorders, we hypothesized that reduced GABA in the dACC would be associated with increased attentional biases towards smoking-related cues. We confirmed this hypothesis among nicotine-dependent tobacco smokers by combining an offline behavioral measure of attentional bias with magnetic resonance spectroscopy. Smokers with the greatest attentional bias also experienced more negative affect during early nicotine withdrawal. Findings revealed a relationship between heightened reactivity to drug cues, and both decreasing dACC GABA and early withdrawal symptoms. Because reduced GABA function in frontal brain regions disrupt cognitive function, our findings suggest that smokers with diminished dACC GABA may lack the cognitive resources to successfully ignore highly salient distractors such as tobacco-related stimuli and therefore might be more prone to cue-induced relapse. This newly discovered relationship between dACC GABA and attentional bias provides evidence for a neurochemical target, which may aid smoking cessation in highly cue-reactive individuals.


Assuntos
Atenção/fisiologia , Sinais (Psicologia) , Giro do Cíngulo/metabolismo , Fumar/metabolismo , Tabagismo/metabolismo , Ácido gama-Aminobutírico/metabolismo , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Fumar/psicologia , Tabagismo/psicologia , Adulto Jovem
19.
Drug Alcohol Depend ; 126(1-2): 251-6, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22578529

RESUMO

BACKGROUND: Isoflavone compounds naturally occurring in the root of the kudzu plant have been used historically to treat alcohol-related problems. A pilot study was conducted to assess the effects of one primary isoflavone--puerarin--for its ability to modify alcohol intake in humans. METHODS: Ten (10) healthy adult volunteers were administered puerarin (1200 mg daily) in a double-blind, placebo-controlled, crossover design experiment for one week prior to an afternoon drinking session lasting 1.5h. Participants had access to up to six bottles of their preferred brand of beer in addition to juice and water. A time course of drinking, sip volumes, and total amount consumed were recorded. RESULTS: Participants consumed on average 3.5 (±0.55) beers when treated with placebo and 2.4 (±0.41) beers when treated with puerarin. In contrast to drinking following placebo treatment when 3 participants drank 5 beers and 1 participant drank all 6 beers, none drank 5 or 6 beers when treated with puerarin. Drinking topography also changed. When treated with puerarin, participants decreased sip size, took more sips to finish a beer, and took longer to consume each beer. Additionally, after finishing a beer, latency to opening the next beer was increased. CONCLUSIONS: This study is the first demonstration that a single isoflavone found in the kudzu root can alter alcohol drinking in humans. These results suggest that alcohol consumption patterns are influenced by puerarin administration and this botanical medication may be a useful adjunct in the treatment of excessive alcohol intake.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Alcoolismo/tratamento farmacológico , Isoflavonas/uso terapêutico , Antagonistas Adrenérgicos beta/efeitos adversos , Adulto , Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/psicologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Isoflavonas/efeitos adversos , Masculino , Adesão à Medicação , Projetos Piloto , Pueraria/química , Adulto Jovem
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