Mmm. That first sip of coffee in the morning. The taste of butter on sourdough toast, perhaps with a dab of raspberry jam. Flavors can make a person’s day—or ruin it, if they arise unbidden. For about 7 percent of patients with schizophrenia and other psychotic disorders, gustatory hallucinations—phantom tastes that arrive suddenly and fade just as quickly—are a common and disturbing part of life.
Moreover, most phantom tastes are far from delicious, says Kathryn Lewandowski, an HMS instructor in psychology at McLean Hospital, who studies psychotic patients to assess the type and range of hallucinations they experience. Rather, the tastes tend to be unsavory and confusing.
“Some people with gustatory hallucinations do experience the taste of specific foods,” Lewandowski says. “But usually they can’t identify the taste; it’s just generally unpleasant.”
Clinicians have traditionally associated gustatory hallucinations—along with hallucinations of smell and touch—with brain tumors and lesions rather than with psychotic disorders. As a result, such phenomena often escape detection. With her study suggesting that gustatory hallucinations are associated with specific types of delusions and an earlier-than-usual onset of psychosis—a possible harbinger of more severe illness—Lewandowski advises clinicians to ask patients whether they have ever experienced such sensations.
“Patients don’t always report them freely,” Lewandowski says. “To fail to ask about them misses information that may be clinically relevant, not just for diagnosis but also for identifying possible treatments.”
Lewandowski and colleagues plan to continue correlating these unusual sensory experiences with other clinical symptoms and to use neuroimaging data in the hope of pinpointing early signs of mental illness.