"And this returns us to madness. Several studies have found that people with extremely mild forms of schizophrenia - they're often referred to as "schizotypal"-- perform above average when solving various lab tasks used to measure creativity. What explains this anomaly? Interestingly, schizotypal subjects also have markedly enhanced right hemisphere function, and are more likely to rely on this hemisphere during normal cognitive processing.

Last speculative point: marijuana also enhances brain activity (at least as measured indirectly by cerebral blood flow) in the right hemisphere. The drug, in other words, doesn't just suppress our focus or obliterate our ability to pay attention. Instead, it seems to change the very nature of what we pay attention to, flattening out our hierarchy of associations."