Delay discounting and task performance consistency in patients with schizophrenia

Area of Science:

• Cognitive Neuroscience
• Psychiatry

Background:

• Schizophrenia (SZ) is associated with impaired goal-oriented behavior.
• Delay discounting tasks assess choices between immediate and delayed rewards.
• Response consistency (R(2)) is often overlooked but critical in SZ.

Purpose of the Study:

• To investigate goal-oriented behavior in schizophrenia using delay discounting.
• To evaluate the impact of response consistency on delay discounting in SZ.

Main Methods:

• A delay discounting task was administered to individuals with schizophrenia (n=35) and healthy controls (n=21).
• The rate of discounting (k) and response consistency (R(2)) were calculated.
• A criterion of R(2)>0.60 defined consistent performance.

Main Results:

• Consistent schizophrenia patients exhibited greater delay discounting than healthy controls.
• Schizophrenia patients showed a less pronounced decrease in immediate choices across trials.
• This group difference was primarily observed in non-smokers.

Conclusions:

• Impaired goal-oriented behavior in schizophrenia is linked to greater delay discounting, particularly in consistent performers.
• Response consistency is a vital factor for validly assessing delay discounting in schizophrenia.
• Aberrant choice patterns in inconsistent schizophrenia patients challenge the interpretation of their discounting rates.