Hippocampal neurogenesis promotes preference for future rewards

Area of Science:

• Neuroscience
• Behavioral Neuroscience

Background:

• Adult hippocampal neurogenesis is linked to reward processing disruptions in various disorders.
• The specific role of new neurons in reward-related decision-making remains unclear.

Purpose of the Study:

• To investigate if adult neurogenesis regulates the preference for future rewards using a delay discounting paradigm in rats.
• To understand the neural mechanisms underlying these decisions.

Main Methods:

• Rats underwent procedures to block neurogenesis.
• A delay discounting task was used to assess reward preference.
• Ventral hippocampus activity and neuronal morphology were analyzed.

Main Results:

• Blocking neurogenesis resulted in aversion to delayed rewards and preference for immediate, smaller rewards.
• Neurogenesis-deficient rats showed reduced ventral hippocampus activity.
• Delay-based decisions altered dendrites and spines in adult-born neurons, with specific ventral dentate gyrus activation.

Conclusions:

• Adult neurogenesis plays a specific role in decisions involving future rewards.
• Newborn neurons in the ventral hippocampus are critical for regulating preference for future, advantageous rewards.
• Findings implicate neurogenesis in disorders characterized by impaired future-oriented decision-making.