Hallucinations in Mice Are Being Used To Study the Nature of Psychotic Disorders

Scientists are pulling back the curtain on a mysterious phenomenon - how hallucinations are produced in the brain.

Transcript

00:00A new study focused on mice has found a key neural circuit that may be responsible for

00:08psychotic disorders.

00:11Researchers at Cold Spring Harbor Laboratory developed a new model of testing after showing

00:16mice are just as susceptible to psychosis as humans are.

00:20Test subjects, humans and mice alike, reported how confidently they heard a sound played

00:26which was obscured with background noise.

00:29Mice were trained to indicate whether they'd heard a sound, demonstrating their confidence

00:34by how long they waited for a reward.

00:36The researchers found that similar to humans, mice were more likely to falsely report sounds

00:42when sounds played more frequently and when a hallucinogen, ketamine, was administered.

00:48By monitoring the rodents' brains, the researchers found elevated dopamine levels preceding hallucinations.

00:55According to senior author Adam Kepiks, a neural circuit in the brain balances prior

01:01beliefs and the higher the baseline level of dopamine, the more people rely on prior

01:06beliefs.

01:07We think that hallucinations occur when this neural circuit gets unbalanced and antipsychotics

01:13rebalance it, he told Washington University's The Source.

01:18While dopamine is known to play a role in psychosis, how the chemical rewires brain

01:23circuitry to produce hallucinations remains a mystery.

01:27The new model could allow researchers to probe deeper and identify new treatments for psychotic

01:33disorders.

01:34Right now, we're failing people with serious psychiatric conditions because we don't really

01:39understand the neurobiology of the disease, Kepiks explained.

01:43We're not going to make progress in treating psychiatric illnesses until we have a good

01:48way to model them in animals.