The Neurology and Psychopathology of Pica

Pica is defined by the American Psychiatric Association's Diagnostic and Statistical Manual, 5th edition (DSM 5) as the ongoing ingestion of materials with no nutritive or food value. More specifically such ingestions must be unremitting for at least 1 month and occur at a developmentally inconsistent age for such behavior. This article reviews the association of pica with pregnancy, micronutrient deficiencies, psychiatric disorders, dementia, and developmental disorders with emphasis on autism spectrum disorders (ASD).

Some variants of non-nutritive consumption are prevalent behavioral norms in non-western cultures, so not all picas should be considered pathological. However, the strong association of pica with iron deficiency anemia (IDA) lends credence to the hypothesis that dopamine transmission may be disrupted in this disorder. Picas associated with ASD are resistant to medications but can be treated with applied behavioral analysis therapy (ABA). Etiological hypotheses for pica are explored with a focus on neurobiological, neuroimaging, and psychiatric correlations. Pharmacological management and behavior modification strategies are also discussed. The possibility that pica is a form of addiction analogous to food cravings is introduced and suggested as an area for further research pursuits.