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Drug use is a choice with immediate positive outcomes, but long-term negative consequences. Thus, the repeated use of drugs in the face of negative consequences suggests dysfunction in the cognitive mechanisms underpinning decision-making. This cognitive dysfunction can be mapped into three stages: the formation of preferences involving valuation of decision options; choice implementation including motivation, self-regulation and inhibitory processes; and feedback processing implicating reinforcement learning. This article reviews behavioral studies that have examined alterations in these three stages of decision-making in people with substance use disorders. Relative to healthy individuals, those with alcohol, cannabis, stimulant and opioid use disorders value risky options more highly during the formation of preferences; have a greater appetite for superficially attractive rewards during choice implementation; and are both more efficient in learning from rewards and less efficient in learning from losses during feedback processing. These observed decision-making deficits are most likely due to both premorbid factors and drug-induced effects. Because decision-making deficits have been prospectively associated with a greater risk of drug relapse, we advocate for greater research on modulating the component stages that give rise to dysfunctional decision-making in disorders of addiction.

INTRODUCTION: Poor social connection is considered a risk factor for dementia. Since socializing behaviors may cluster together or act compensatorily, we aimed to investigate social connection patterns and their association with dementia, for men and women separately. METHODS: A total of 12,896 community‐dwelling older adults (mean ± SD age: 75.2 ± 4.3 years, 54% women) without major cognitive impairment were included. Latent class analysis was conducted using 24 baseline social connection indicators. Cox proportional hazards regression was used to estimate the association between latent classes and incident dementia over 12 (median: 8.4) years follow‐up. RESULTS: Three distinct classes were identified in both genders: strong social connections with an intermediate friend‐relative network (Class 1: men, 43.8%; women, 37.9%), weak social connections (Class 2: men, 29.6%; women, 27.4%), and strong social connections with a larger friend‐relative network (Class 3: men, 26.6%; women, 34.7%). Compared to Class 1, men in Class 2 (HR: 1.38, 95% CI: 1.08‐1.77) and women in Class 3 (HR: 1.27, 95% CI: 1.01‐1.60) had an increased risk of dementia. DISCUSSION: Dementia risk varies with different social connection patterns among older men and women. Highlights: Three distinct social connection patterns were identified based on 24 indicators.These patterns were related to dementia risk differently in men and women.In men, a weak social connection pattern was associated with a higher dementia risk.In women, a strong social connection with a relatively larger friend‐relative network was associated with a greater dementia risk. [ABSTRACT FROM AUTHOR]

Apathy is one of the most common neuropsychiatric features of Huntington's disease. A hallmark of apathy is diminished goal-directed behaviour, which is characterized by a lower motivation to engage in cognitively or physically effortful actions. However, it remains unclear whether this reduction in goal-directed behaviour is driven primarily by a motivational deficit and/or is secondary to the progressive cognitive and physical deficits that accompany more advanced disease. We addressed this question by testing 17 individuals with manifest Huntington's disease and 22 age-matched controls on an effort-based decision-making paradigm. Participants were first trained on separate cognitively and physically effortful tasks and provided explicit feedback about their performance. Next, they chose on separate trials how much effort they were willing to exert in each domain in return for varying reward. At the conclusion of the experiment, participants were asked to rate their subjective perception of task load. In the cognitive task, the Huntington's disease group were more averse to cognitive effort than controls. Although the Huntington's disease group were more impaired than controls on the task itself, their greater aversion to cognitive effort persisted even after controlling for task performance. This suggests that the lower levels of cognitive motivation in the Huntington's disease group relative to controls was most likely driven by a primary motivational deficit. In contrast, both groups expressed a similar preference for physical effort. Importantly, the similar levels of physical motivation across both groups occurred even though participants with Huntington's disease performed objectively worse than controls on the physical effort task, and were aware of their performance through explicit feedback on each trial. This indicates that the seemingly preserved level of physical motivation in Huntington's disease was driven by a willingness to engage in physically effortful actions despite a reduced capacity to do so. Finally, the Huntington's disease group provided higher ratings of subjective task demand than controls for the cognitive (but not physical) effort task and when assessing the mental (but not the physical) load of each task. Together, these results revealed a dissociation in cognitive and physical motivation deficits between Huntington's disease and controls, which were accompanied by differences in how effort was subjectively perceived by the two groups. This highlights that motivation is the final manifestation of a complex set of mechanisms involved in effort processing, which are separable across different domains of behaviour. These findings have important clinical implications for the day-to-day management of apathy in Huntington's disease. [ABSTRACT FROM AUTHOR]

Objectives This study examines the gender-specific associations between a wide range of social activities and dementia risk. Methods A prospective cohort study was conducted involving community-dwelling older Australians (≥70 years) without significant cognitive impairment at enrolment. During the first year of enrolment, we assessed 25 self-reported social activities covering various aspects, including support from relatives and friends, community participation, social interactions with surroundings, and loneliness. Dementia diagnosis followed DSM-IV criteria, adjudicated by an international expert panel. To estimate hazard ratios (HR) and 95% confidence intervals (CI) for associations between social activities and dementia, we performed Cox proportional hazards models, adjusting for age, educational attainment, baseline global cognition, and depressive symptoms. Results Among 9,936 participants who completed all social activity questionnaires (median [IQR] age: 73.4 [71.6–77.1] years; 47.4% men), dementia was diagnosed in 3.8% of men (n  = 181/4,705) and 2.6% of women (n  = 138/5,231) over a median 6.4 years (IQR: 5.3–7.6, range: 0.2–10.1) follow-up. Gender-specific relationships emerged: caregiving for a person with illness/disability in women (HR: 0.65, 95% CI: 0.42–0.99), and having ≥9 relatives feeling close to call for help in men (HR: 0.56, 95% CI: 0.33–0.96; reference <9 relatives) were associated with reduced dementia risk. Unexpectedly, in women, having ≥5 friends with whom they felt comfortable discussing private matters were associated with a greater dementia risk (HR: 1.69, 95% CI: 1.10–2.59; reference ≤2 friends). Imputed models further identified that babysitting/childminding was associated with lower dementia risk in men (HR: 0.75, 95% CI: 0.56–0.99). No other social activities showed significant associations with dementia. Discussion This study provides evidence of social activities influencing dementia risk. Further investigations are required to uncover the mechanisms driving these observed relationships. [ABSTRACT FROM AUTHOR]