“The research on Toxoplasma gondii has thrown up some interesting findings. We know, for instance, that infections are more common amongst people with certain psychiatric disorders, such as schizophrenia and bipolar disorder. But even more disconcerting is the link to a condition called ‘intermittent explosive disorder’. Those with IED are prone to moments of uncontrolled aggression; one of the symptoms is an increased tendency to display road rage, for example”