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61.
Thirty-one Type 1 diabetic patients entered a 12-month education programme in which attitudes to diabetes, knowledge of diabetes, and technical competence were assessed using questionnaires and practical tests. A closely matched group of 25 control patients continued to receive routine clinic care. Patients completing the education programme showed improved blood glucose control (HbA1 decreased from 11.8 +/- 0.4% to 10.5 +/- 0.3%, mean +/- SE, p less than 0.01), whereas blood glucose control was not altered in the control group (HbA1 11.8 +/- 0.5% before and 11.6 +/- 0.4% after 12 months). Patients completing the education programme also showed greater knowledge (p less than 0.001), more favourable attitudes (p less than 0.03), and increased competence in technical skills (p less than 0.02) compared with the control group. Six months after completing the programme blood glucose control deteriorated (HbA1 11.0 +/- 0.4%, p less than 0.05), although knowledge, attitudes, and technical competence were unchanged. This might reflect the withdrawal of extrinsic motivation and attention provided during the programme. Thus consideration should be given to development of the patient's intrinsic motivation to prolong the benefits of diabetes education programmes.  相似文献   
62.
Rationale  Mesolimbic dopamine (DA) is a critical component of the brain circuitry regulating behavioral activation and effort-related processes. Research involving choice tasks has shown that rats with impaired DA transmission reallocate their instrumental behavior away from food-reinforced tasks with high response requirements and instead select less effortful food-seeking behaviors. Objective  Previous work showed that adenosine A2A antagonism can reverse the effects of the DA antagonist haloperidol in an operant task that assesses effort-related choice. The present work used a T-maze choice procedure to assess the effects of adenosine A2A and A1 antagonism. Materials and methods  With this task, the two arms of the maze have different reinforcement densities (four vs. two food pellets), and a vertical 44 cm barrier is positioned in the arm with the higher density, presenting the animal with an effort-related challenge. Untreated rats strongly prefer the arm with the high density of food reward and climb the barrier in order to obtain the food. Results  Haloperidol produced a dose-related (0.05–0.15 mg/kg i.p.) reduction in the number of trials in which the rats chose the high-barrier arm. Co-administration of the adenosine A2A receptor antagonist MSX-3 (0.75, 1.5, and 3.0 mg/kg i.p.), but not the A1 antagonist 8-cyclopentyl-1,3-dipropylxanthine (0.75, 1.5, and 3.0 mg/kg i.p.), reversed the effects of haloperidol on effort-related choice and latency. Conclusions  Adenosine A2A and D2 receptors interact to regulate effort-related decision making, which may have implications for the treatment of psychiatric symptoms such as psychomotor slowing or anergia that can be observed in depression, parkinsonism, and other disorders.  相似文献   
63.
The aim of this study was to determine how sense of control and intrinsic motivation are related to university students' motivational structure and alcohol consumption. Participants were 94 university students who completed the Personal Concerns Inventory, Shapiro Control Inventory, Helplessness Questionnaire, Intrinsic–Extrinsic Aspirations Scale, and Alcohol Use Questionnaire. Results showed that sense of control and intrinsic motivation were positively correlated with adaptive motivation and negatively correlated with alcohol consumption. Mediational analyses indicated that adaptive motivation fully mediated the relationship between sense of control/intrinsic motivation and alcohol consumption.  相似文献   
64.
Many therapies designed to reduce food intake and body weight act, in part, by blocking the dopamine transporter (DAT) — a protein responsible for clearing extracellular dopamine (DA) after release thereby terminating its action. Here, we found that a single injection of the drug trodusquemine (MSI-1436) decreased food intake in rats. To assess the effects of MSI-1436 on DAT function, fast-scan cyclic voltammetry was used to measure DA concentration changes in the ventral striatum. DA release was evoked by electrical stimulation of the ventral tegmental area every 5 min. After 3 baseline measurements, rats were injected with MSI-1436 (10 mg/kg), the known DAT blocker bupropion (80 mg/kg) or saline and evoked DA release and reuptake were monitored for an additional hour. Neither saline nor MSI-1436 caused a significant change in the magnitude of evoked release from baseline values whereas bupropion caused a significant increase. In addition, neither saline nor MSI-1436 significantly increased DA decay rates while such an increase was observed with bupropion. Thus, over a time course when MSI-1436 suppresses food intake it does not affect DAT function. The results support MSI-1436 as an anti-obesity treatment which spares DAT.  相似文献   
65.
Microinjection of apomorphine into the ventral tegmental area (VTA) of male rats was previously shown to delay the onset of copulation and slow its rate, presumably by stimulating impulse-regulating autoreceptors on cell bodies of the A10 mesocorticolimbic dopamine tract. Such stimulation would be expected to slow the firing rate of these neurons and, thereby, to impair locomotion and/or motivational processes. The present experiments tested whether the delayed onset and slowed rate of copulation were related to deficits in motor performance, sexual motivation, and/or genital reflexes. In X-maze tests the speed of running to all 4 goal boxes was slowed; however, the percentage of trials on which the male chose the female's goal box was not decreased. Examination of videotaped copulation tests revealed that the male showed fewer complete copulatory behaviors (mounts, intromissions, and ejaculations), but more misdirected or incomplete copulatory attempts after apomorphine in the VTA. There were also fewer scores of active, as opposed to inactive, behaviors, and the onset and rate of copulation were slowed. The total number of female directed behaviors was not different in apomorphine tests, compared to vehicle. Finally, tests of ex copula genital reflexes revealed no significant effects of apomorphine in the VTA on erections, penile movements, or seminal emissions. These data suggest a role of the VTA in the motor aspects and/or sensorimotor integration of copulation. Sexual motivation and ex copula genital reflexes appeared to be unaffected by apomorphine in the VTA.  相似文献   
66.
ObjectiveMotivating older adults to follow up with an outpatient clinician after discharge from emergency departments (ED) is beneficial yet challenging. We aimed to answer whether psychological needs for motivation and discrete emotions observed by care transition coaches would predict this behavioral outcome.MethodsCommunity-dwelling older adults following ED discharge were recruited from three EDs in two U.S. states. We examined home visit notes documented by coaches (N = 725). Retrospective chart reviews of medical records tracked participants’ health care utilization for 30 days.ResultsObserved knowledge-based competence predicted higher likelihood of outpatient follow-up within 30 days, while observed sadness predicted a lower likelihood of follow-up within seven days following discharge. Moreover, participants who demonstrated happiness were marginally more likely to have an in-person follow-up within seven days, and those who demonstrated knowledge-based competence were more likely to have an electronic follow-up within 30 days.ConclusionsKnowledge-based competence and emotions, as observed and documented in coach notes, can predict older adults’ subsequent outpatient follow-up following their ED-discharge.Practice implicationsIntervention programs might encourage coaches to check knowledge-based competence and to observe emotions in addition to delivering the content. Coaches could also customize strategies for patients with different recommended timeframes of follow-up.  相似文献   
67.
We randomized 332 women, 18-24 years old, who were not explicitly seeking treatment for their marijuana use to either a two-session motivationally focused intervention or an assessment-only condition. Assessed by timeline follow-back methodology, participants reported using marijuana 57% of days in the 3 months prior to study entry. Intervention effects on the likelihood of marijuana use were not statistically significant at 1 month (odds ratio [OR] = 0.77, p = .17), significant at 3 months (OR = 0.53, p = .01), and no longer significant at 6 months (OR = 0.74, p = .20). Among the 61% of participants endorsing any desire to quit using marijuana at baseline, significant intervention effects on the likelihood of marijuana use days were observed at 1 month (OR = 0.42, p = .03), 3 months (OR = 0.31, p = .02), and 6 months (OR = 0.35, p = .03). A two-session brief motivational intervention reduced marijuana use among young women not seeking treatment. Women with a desire to quit showed a greater and more durable response.  相似文献   
68.
The error-related negativity (ERN) is thought to index a neural behavior monitoring system with its source in anterior cingulate cortex (ACC). While ACC is involved in a wide variety of cognitive and emotional tasks, there is debate as to what aspects of ACC function are indexed by the ERN. In one model the ERN indexes purely cognitive function, responding to mismatch between intended and executed actions. Another model posits that the ERN is more emotionally driven, elicited when an action is inconsistent with motivational goals. If the ERN indexes mismatch between intended and executed actions, then it should be insensitive to motivational valence, e.g. reward or punishment; in contrast if the ERN indexes the evaluation of responses relative to goals, then it might respond differentially under differing motivational valence. This study used a flanker task motivated by potential reward and potential punishment on different trials and also examined the N2 and P3 to the imperative stimulus, the response Pe, and the FRN and P3 to the outcome feedback to assess the impact of motivation valence on other stages of information processing in this choice reaction time task. Participants were slower on punishment motivated trials and both the N2 and ERN were larger on punishment motivated trials, indicating that loss aversion has an impact on multiple stages of information processing including behavior monitoring.  相似文献   
69.
Recently, we showed that another person's gaze direction influenced the perceiver's frontal EEG asymmetry and autonomic arousal in response to freely viewed real faces, but not in response to face pictures. However, the lack of a task during the viewing may have resulted in less attention allocation to face pictures vs. live faces. In the present study, the participants performed two online tasks while viewing the faces presented live through an electronic shutter and as pictures on a computer screen. The results replicated those from our previous experiment showing that direct gaze elicited greater relative left-sided frontal EEG asymmetry and autonomic arousal than averted gaze but, again, only in the live condition. However, the results also showed that two live stimulus faces (male and female) elicited differential EEG asymmetry responses in our participants (all females), and the effects of gaze direction were observed only for the (live) female faces. The results suggest that the discriminative responses to live faces vs. pictures are likely to reflect the participants' enhanced mental-state attributions and self-awareness when looking at and being looked by live faces. Thus, the motivation- and affect-related psychophysiological responses to gaze direction are most discriminative in the presence of another person, regardless of whether the face/gaze is actively monitored or not.  相似文献   
70.
Collins et al. (2012) indicated that time spent in a project-based Housing First (HF) intervention was associated with improved two-year alcohol-use trajectories among chronically homeless individuals with alcohol problems. To explore potential correlates of these findings, we tested the relative prediction of alcohol-use outcomes by motivation to change (MTC) and substance abuse treatment attendance. Participants (N=95) were chronically homeless individuals with alcohol problems receiving a project-based HF intervention in the context of a larger nonrandomized controlled trial (Larimer et al., 2009). Participants were interviewed regularly over the two-year follow-up. Treatment attendance and MTC were measured using items from the Addiction Severity Index and the SOCRATES, respectively. Alcohol-use outcomes included alcohol quantity, problems and dependence. Generalized estimating equation modeling indicated that MTC variables and not treatment attendance consistently predicted alcohol-use outcomes over the two-year follow-up. Findings suggest that the importance of motivation to change may outweigh treatment attendance in supporting alcohol behavior change in this population.  相似文献   
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