“…the hippocampus (associated with memory) and the nucleus accumbens (associated with pleasure) work together in making critical decisions of this type, where time plays a role. The researchers showed that when these two structures were effectively ‘disconnected’ in the brain, there is a disruption of decisions related to delayed gratification.”
[Note: Nothing to do with the frontal lobes!]– following disruption of the circuit connecting the hippocampus and nucleus accumbens, the rats became impatient and unwilling to wait, even for a few seconds.
– They always selected the immediate reward despite its smaller size.
Importantly, lesions to other parts of the brain, including the prefrontal cortex, known to be involved in certain aspects of decision-making, did not cause this behavioural change.
[So much for the whole cortical/frontal lobe model of behavior control, duh!}
“This is a type of decision-making that many of us grapple with in daily life, particularly the very young, the very old, and those with brain disease,”
“In some ways this relationship makes sense; the hippocampus is thought to have a role in future planning, and the nucleus accumbens is a “reward” center and a major recipient of dopamine, a chemical responsible for transmitting signals related to pleasure and reward, but we couldn’t have imagined that the results would be so clear. In addition to providing a deeper understanding of decision-making, our results highlight the potential of this circuit, involving the hippocampus and nucleus accumbens, to be a therapeutic target in human patient groups.”