Method: Volitional slow-deep breathing (Vs) and volitional fast-shallow breathing (Vf) were assigned to young females (mean age = 21.18 ± 1.69 years) during working memory (WM) tasks with emotional distractors. Results & Discussion: Reductions in WM accuracy and reaction speed due to emotional distractors were alleviated by Vs and spontaneous slow breathing response. On the other hand, Vf increased WM reaction speed but not WM accuracy, implying an improvement in motor execution rather than in mental functions. Interestingly, effects on the autonomic nervous system (ANS) of volitional breathing and spontaneous slow breathing resembled the relief of mental fatigue and the orienting reflex, respectively. These phenomena suggest underlying mechanisms for breathing interventions. Summary: Volitional slow-deep breathing and spontaneous slow breathing attenuate emotional distraction. Meanwhile, the effect of volitional fast-shallow breathing likely facilitates motor function. Especially, concurrent ANS responses are associated with the beneficial effects of slow breathing patterns during mental stress.