Event-related potential paradigms for delay discounting in schizophrenia: Five paradigms and a methodological roadmap

Table 3 Summary of event-related potentials paradigms for delay discounting studies

Paradigm	Key parameters	Primary ERP components	Remarks for schizophrenia applicability
Classical hypothetical delay discounting task	Binary choice between SS vs LL; delays ranging from 1 day to 6 months; parametric variation of reward amounts; Kirby titration or McClure orthogonal design	P300, RewP, CNV, N2, P2	Clear behavioral phenotype (elevated discounting) and well-documented P300 abnormalities; no direct ERP study yet; recommended as firstchoice paradigm
Delay discounting with risk	Simultaneous manipulation of delay (short/Long) and probability (high/Low); typically a 2 × 2 design	N1, P2, N2, N400, LPC, P300	Allows dissociation of risk and time discounting; suitable for examining probabilistic reasoning biases
Emotionprimed intertemporal choice	Presentation of emotional pictures/faces (e.g., disgust, anger, gratitude) before each choice; pre-rating of valence and arousal recommended (e.g., IAPS/CAPS)	N1, P2, P3, LPP, SPN, EPN	Useful for studying interaction between affective processing and decisionmaking; can explore negative symptom mechanisms (anhedonia)
Loss-framed intertemporal choice	Monetary losses instead of gains; symmetric design with gain frame to compare gain-loss asymmetry	P2, N2, P3	Reveals asymmetry of loss aversion; suitable for testing emotion regulation deficits
Social distance/social comparison intertemporal choice	Decisions for self, friend, or stranger; may include social comparison feedback	N1, P2, P3 (P3a/P3b), LPP	Explores the neural basis of social cognition deficits; recommended for patients with relatively preserved cognitive function

ERP: Event-related potential; SS: Smaller-sooner; LL: Larger-later; RewP: Reward positivity; CNV: Contingent negative variation; LPC: Late positive component; IAPS: International affective picture system; CAPS:Chinese affective picture system; LPP: Late positive potential; SPN: Stimulus preceding negativity; EPN: Early Posterior negativity.