Men Are at Higher Risk of Screening Positive for Vascular Cognitive Impairment Compared to Women after Stroke and Transient Ischemic Attack.

While women have greater incidence of dementia, men have higher prevalence of vascular risk factors. This study examined sex differences in risk of screening positive for cognitive impairment after stroke. Ischemic stroke/TIA patients (N = 5969) participated in this prospective, multi-centered study, which screened for cognitive impairment using a validated brief screen. Men showed a higher risk of screening positive for cognitive impairment after adjusting for age, education, stroke severity, and vascular risk factors, suggesting that other factors may be contributing to increased risk among men (OR = 1.34, CI 95% [1.16, 1.55], p < 0.001). The effect of sex on cognitive impairment after stroke warrants further attention.

Parallel ventral hippocampus-lateral septum pathways differentially regulate approach-avoidance conflict.

The ability to resolve an approach-avoidance conflict is critical to adaptive behavior. The ventral CA3 (vCA3) and CA1 (vCA1) subfields of the ventral hippocampus (vHPC) have been shown to facilitate avoidance and approach behavior, respectively, in the face of motivational conflict, but the neural circuits by which this subfield-specific regulation is implemented is unknown. We demonstrate that two distinct pathways from these subfields to lateral septum (LS) contribute to this divergent control. In Long-Evans rats, chemogenetic inhibition of the vCA3- LS caudodorsal (cd) pathway potentiated approach towards a learned conflict-eliciting stimulus, while inhibition of the vCA1-LS rostroventral (rv) pathway potentiated approach non-specifically. Additionally, vCA3-LScd inhibited animals were less hesitant to explore food during environmental uncertainty, while the vCA1- LSrv inhibited animals took longer to initiate food exploration. These findings suggest that the vHPC influences multiple behavioral systems via differential projections to the LS, which in turn send inhibitory projections to motivational centres of the brain.