A case of persistent visual hallucinations of faces following LSD abuse: A functional Magnetic Resonance Imaging study

Abstract

In this study, we report the case of a patient experiencing hallucinations of faces that could be reliably precipitated by looking at trees. Using functional Magnetic Resonance Imaging (fMRI), we found that face hallucinations were associated with increased and decreased neural activity in a number of cortical regions. Within the same fusiform face area, however, we found significant decreased and increased neural activity according to whether the patient was experiencing hallucinations or veridical perception of faces, respectively. These findings may indicate key differences in how hallucinatory and veridical perceptions lead to the same phenomenological experience of seeing faces.

Keywords:

• Faces
• Fusiform gyrus
• fMRI
• LSD abuse
• Schizoaffective disorder
• Visual hallucinations

We thank Luigi Pizzamiglio and Vince Di Lollo for helpful comments on an early version of the manuscript, and the staff at the UBC MRI Research Centre for technical assistance. This study was supported by operating grants from the National Institute of Mental Health (RO1-MH069898) and Canadian Institutes of Health Research (CIHR) (MOP-77615). GI is supported by the Michael Smith Foundation for Health Research (MSFHR) and the Alzheimer Society of Canada. CJF and MS are supported by the CIHR, and CJF by the MSFHR. JJSB is supported by a Canada Research Chair and a MSFHR Senior Scholar Award.