Ayahuasca, a psychoactive tea made from Banisteriopsis caapi and Psychotria viridis and used in religious contexts, was tested for its effect on the number of neuronal cell bodies in the mouse cerebral cortex. Fifteen mice were divided into three groups: a control group given saline for 15 days, a group given a single dose of ayahuasca extract, and a group given the extract daily for 15 consecutive days (dose 30 mg/ml). Alkaloids were confirmed in the tea. Image analysis showed no difference in the quantity of cortical neuronal cell bodies between the control group and either experimental group. The tea, at the dose and duration used, caused no quantitative change in neuronal cell bodies in the mouse cerebral cortex.
In mice, daily administration of ayahuasca extract for 15 days did not alter the number of neuron cell bodies in limbic, sensory, or motor areas of the cerebral cortex compared to a control group. A single dose also produced no change. The study counted neuron cell bodies in three groups of five mice each: one control group given saline, one given a single 30 mg/ml dose of ayahuasca extract, and one given the same dose daily for 15 days. The authors conclude that, at this dose and duration, ayahuasca does not affect neuron cell body counts in the examined cortical regions.