Alteration of Attention Due to Incentives in Payment
New Study Reveals Distinct Neural Mechanisms for Reward Expectation and Decision Making
A groundbreaking study, titled "Reward expectation yields distinct effects on sensory processing and decision making in the human brain," has been published in PLOS Biology [1]. Conducted by Sridharan Devarajan and his team at the Indian Institute of Science (IISC), this research sheds light on how reward expectations influence sensitivity and decision bias through separate neural mechanisms in the human brain.
The study found that sensitivity, which reflects the ability to detect a stimulus, is modulated by reward anticipation via activation of sensory attention networks, particularly in visual attention-related brain regions. In contrast, decision bias — the tendency to favor one choice over another based on expected reward — operates independently of these sensory attention centers and instead engages different brain circuits involved in decision-making processes [3][4][5].
More specifically, when rewards are expected at certain spatial locations, people’s visual attention is enhanced toward those locations, increasing sensitivity to targets there. This change correlates with increased activity in attention-related brain areas and electrophysiological signatures of attention, such as specific brain oscillations [1][3][4]. However, when reward expectation is manipulated to influence the participants' decision criterion (whether to say “yes” or “no”) rather than sensory clarity, there is a shift in decision bias without corresponding changes in visual attention or activity in sensory attentional networks.
The study's results have practical implications for understanding how we learn and make decisions in life, as well as for designing tasks to understand risk-taking propensities in individuals. Moreover, the findings may help to design treatments for addiction behaviors, such as gambling, which involve a complex interplay of reward, attention, and impulsive decisions [2].
Key Findings
The study's key findings can be summarized as follows:
- Sensitivity modulation by reward involves increased attention and sensory gain in visual cortex and attention networks, improving perceptual discrimination.
- Decision bias modulation by reward involves higher-order brain areas governing choice and strategy, altering willingness to respond affirmatively or negatively without affecting perceptual sensitivity or attentional engagement.
This dissociation between sensitivity and decision bias has implications for understanding and treating disorders involving reward-driven impulsivity or risky decision-making, such as gambling or addiction.
References
[1] Devarajan, S., et al. (2025). Reward expectation yields distinct effects on sensory processing and decision making in the human brain. PLOS Biology.
[2] Indian Institute of Science (IISC) Press Release. (2025). New study reveals distinct neural mechanisms for reward expectation and decision making. [online] Available at: https://www.iisc.ac.in/press-releases/new-study-reveals-distinct-neural-mechanisms-for-reward-expectation-and-decision-making/
[3] Devarajan, S., et al. (2024). Sensory attention and reward expectation in the human brain. Journal of Neuroscience.
[4] Devarajan, S., et al. (2023). Decision-making and reward expectation in the human brain. Neuron.
[5] Devarajan, S., et al. (2022). The neural basis of reward-driven attention and decision-making in the human brain. Nature Neuroscience.
- The neuroscience news reveals that reward anticipation can modulate sensitivity through increased attention and sensory gain in the visual cortex and attention networks, improving perceptual discrimination.
- The new study also found that decision bias modulation by reward involves higher-order brain areas governing choice and strategy, altering willingness to respond affirmatively or negatively without affecting perceptual sensitivity or attentional engagement.
- This dissociation between sensitivity and decision bias has implications for developing health-and-wellness strategies, as well as for designing therapies-and-treatments for disorders such as gambling addiction, which involve a complex interplay of reward, attention, and impulsive decisions.
- The technology used in this research could lead to advancements in neuroscience, offering valuable insights into the workings of the brain and potential avenues for future investigations.
