HRH3 and Cognitive impairment: In addition, the H3R antagonist/inverse agonist GSK189254 was found to significantly improve performance of rats in diverse cognition paradigms, including inhibitory passive avoidance, water maze, object recognition, and attentional set-shifting, signifying the potential role of targeting H3Rs for the symptomatic treatment of dementia in AD and other cognitive disorders (Medhurst et al., 2007).