Serotonergic neurons are also involved in breathing systems. Their actions are diverse and dependent upon the activity level and species of the animal. Serotonin plays a critical role in altering the pacemaker neurons involved in gasping and normal respiratory activity. Blocking of the 5-HT2 receptor eliminates the bursts occurring in the pacemaker neurons and leads to the abolishing of gasps. The blocking of this receptor is therefore problematic, especially in SIDS, because gasping is an important mechanism involved in autoresuscitation. A lack of serotonin binding to the serotonin receptor 2 leads to the inability to autoresuscitation due to the lack of drive for gasping.