请帮忙翻这段英语（不要机翻,While most research on contagious yawning emph

请帮忙翻这段英语（不要机翻,
While most research on contagious yawning emphasizes the influence of interpersonal and emotional-cognitive variables on its expression,this report adds to accumulating research suggesting that the underlying mechanism for yawning,both spontaneous and contagious forms,is involved in regulating brain temperature.In turn,the cooling of the brain functions to improve arousal and mental efficiency.The authors of this study suggest that the spreading of this behavior via contagious yawning could therefore function to enhance overall group vigilance.