Given the consistent findings from the present study (Figs. 2, 3 and 8), and previous studies in rats both under general anesthesia25 and across sleep–wake states56, that acetylcholinesterase inhibition at the HMN suppresses tongue motor activity, it would be unlikely that any beneficial effects of acetylcholinesterase inhibitors in OSA patients would be due to effects at the HMN. Here, ACHE is linked to obstructive sleep apnea syndrome.