Editing Paranoia (section)

===Physical===
A paranoid reaction may be caused from a decline in brain circulation as a result of high blood pressure or hardening of the arterial walls.<ref name=D&F/>

Drug-induced paranoia, associated with [[cannabis (drug)|cannabis]] and stimulants like [[amphetamines]] or [[methamphetamine]], has much in common with schizophrenic paranoia; the relationship has been under investigation since 2012. Drug-induced paranoia has a better prognosis than schizophrenic paranoia once the drug has been removed.<ref>{{cite journal|title=Amphetamine-induced psychosis – a separate diagnostic entity or primary psychosis triggered in the vulnerable?|journal=BMC Psychiatry|volume=12|pages=221|pmc=3554477|year=2012|doi=10.1186/1471-244X-12-221|pmid=23216941|last1=Bramness|first1=J. G|last2=Gundersen|first2=Øystein Hoel|last3=Guterstam|first3=J|last4=Rognli|first4=E. B|last5=Konstenius|first5=M|last6=Løberg|first6=E. M|last7=Medhus|first7=S|last8=Tanum|first8=L|last9=Franck|first9=J |doi-access=free }}</ref> For further information, see [[stimulant psychosis]] and [[substance-induced psychosis]].

Based on data obtained by the Dutch NEMESIS project in 2005, there was an association between impaired hearing and the onset of symptoms of psychosis, which was based on a five-year follow up. Some older studies have actually declared that a state of paranoia can be produced in patients that were under a hypnotic state of deafness. This idea however generated much skepticism during its time.<ref name="paranoia">Bentall and Taylor (2006), p.281</ref>