A long-term ecstasy-related change in visual perception

Brown, J., Edwards, M., McKone, E., & Ward, J. (2007). A long-term ecstasy-related change in visual perception. Psychopharmacology, 193(3), 437-446.

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I chose this article because I thought it would be interesting to look for drugs effect on the vision centers of the brain. Ecstasy is a popular recreational drug used today however many users do not realize the lasting damage to their brain after long term use. The present article looks at long -term consequences of ecstasy use on the occipital lobe.Ecstacy is known to cause changes to serotonin system in chronic users. Serotonin may be involved lateral inhibition between orientation sensitive neurons in the occipital lobe. The researchers wanted to look at behavioral changes in the occipital lobe using a tilt aftereffect illusion. Thirty ecstasy users and thirty four non drug users were used as controls. Drug use histories were obtained from each participant. The experimenters used a Gabor which is sinusoidal variation of luminance level within a Gaussian window displayed on a screen. The participants were asked to sit with their head on a chin rest, with their eyes level with the center of the monitor. A curved –forehead rest was used to restrict head tilt. A series of lines showed up on the screen and the experiment consisted of three phases. The pre-adaptation test, the adaptation phase and the post- adaptation test were performed. The participants indicated if they perceived that the lines in the Gabor had been sloped to the left or the right using two keys on the keyboard. The results showed that ecstasy users who had not used amphetamines for115 days or more had a larger average tilt aftereffect than non-drug using controls after adaptation to forty degrees stimuli but not after adaptation to 15 degrees stimuli. The results were consistent with the researcher’s idea that long term ecstasy damage to the serotonin system causes behavioral changes on visual perception. The article does prove that there can be harmful effect