Cannabis The use of cannabis or marijauana, commonly known as pot, increases neural noise in the brain and can lead to a point where the person using the drug can lose contact with external reality, according to an Indian-origin researcher.

The neural noise leads to a severe mental disorder in which thought and emotions are so impaired that contact is lost with external reality for the user, the researcher warned, according to an IANS report.

A research team from Yale University found that a primary active constituent of cannabis called '?9-THC' generates psychosis like effects in healthy persons and their behaviour is akin to that of those who show symptoms of schizophrenia.

"At doses roughly equivalent to half or a single joint, the compound called '?9-THC' produced psychosis-like effects and increased neural noise in humans," explained senior author Dr Deepak Cyril D'Souza, professor of psychiatry.

The investigators studied the effects of "?9-THC" on electrical brain activity in 24 human subjects who participated in a three-day study and the findings run contrarty to the general notion gaining ground in society that smoking marijuana is good for recreation and does not cause harm to users.

If confirmed, the link between neural noise and psychosis could shed light on the biology of some of the symptoms associated with schizophrenia, said the IANS report.

"This interesting study suggests a commonality between the effects on the brain of the major active ingredient in marijuana and symptoms of schizophrenia," stated Dr John Krystal, editor of the journal Biological Psychiatry that published the paper.