The String Test

Confabulation is a fascinating symptom where someone forms false memories, perceptions, or beliefs of the self or the environment. A person with confabulation doesn't just have poor memory; they make up their memories. We have a patient on our service with possible Korsakoff syndrome, a late neuropsychiatric manifestation of chronic alcohol use leading to thiamine deficiency. The string test was amazing in identifying confabulation. The resident pretended to reach into his pocket and pull out a piece of string. He unfurled this imaginary string in front of the patient, saying "Now I have a piece of string here, can you tell me what color it is?" The patient looked at the expanse of air between the resident's hands and replied, "Well, I'm color blind, so it could be red or blue or white or black." It was one of the most amazing things I've seen this rotation.