From self to others Neural and social perspectives on cue-triggered decision-making

Predictable, reward-related cues in the environment play a crucial role in guiding behavior and shaping decision-making. Through a series of experiments, this dissertation investigates the role of the motor cortex in cue-triggered decision-making and examines whether the influence of environmental cues on behavior can be transmitted through observation or vicarious reward.
Chapter 1 reviews key theories and findings on environmental cues, the Pavlovian-to-Instrumental Transfer (PIT) paradigm, mirror neuron systems, vicarious transfer and reward, and the use of transcranial magnetic stimulation (TMS) and motor-evoked potentials (MEPs).
Chapter 2 employs an extended PIT task combined with single-pulse TMS to examine motor cortex activation during cue-triggered decision-making. Results confirm the behavioral influence of cues but indicate that the motor cortex is not directly involved in this process.
Chapter 3 summarizes EEG findings from the PIT task and proposes methodological refinements for MEP collection to more accurately capture cue-related motor activity.
Chapter 4 implements these refinements, recording MEPs closer to cue onset, replicating earlier behavioral effects, and finding no evidence of direct motor cortex involvement.
Chapter 5 introduces a vicarious PIT paradigm, demonstrating that cue-driven behavioral influences can extend to observers through mere observation.
Chapter 6 shows that PIT effects persist for rewards delivered to others, remaining insensitive to outcome devaluation but potentially modulated by reward intensity.
Chapter 7 synthesizes these findings, highlighting the limited role of the motor cortex in cue-triggered decision-making and the potential for environmental cues to shape behavior socially and vicariously. Limitations and future research directions are also discussed.