One of the stereotypes of aging is being set in one's ways, and no longer wanting to seek out novel experiences or learn new things. A recent study has provided some evidence pointing to the (natural) deterioration of the locus coeruleus area of the brainstem as contributing to this phenomenon:
https://www.pnas.org/doi/10.1073/pnas.2322617121
The locus coeruleus (Latin: blue place) is a region of the brainstem near the core of consciousness. It is the main region that distributes noradrenaline signaling widely throughout the brain. Noradrenaline is the middle product in a synthesis chain that goes from dopamine->noradrenaline->adrenaline, a chemical pathway that maps nicely to the psychological continuum of "escalating arousal". Noradrenaline is often associated with "arousal", "attention", "motivation", and emotions like anger. It is part of the ascending activation system that wakes you up in the morning.
The locus coeruleus (LC) is active while awake and quiescent while sleeping, except for activations during REM sleep. It
In neuromythography, the left locus coeruleus is call Ajñāna, after the Hindu philosophy school of radical skepticism that rejected most supposed knowledge. The right LC is called The Fool, after the starting Tarot card archetype that calls for an empty state of mind. Noradrenaline is named Kohonen in neuromythography, after Finnish computer scientist Teuvo Kohonen. Kohonen is most known for inventing self-organizing maps, an early form of unsupervised machine learning. Unsupervised machine learning means having no preconceived rules or models guiding the learning, but for the network to learn solely by perceiving the data itself.
We may view the LC as promoting a mental state of ignorance and openness (Ajñāna / The Fool), whose mechanism is to distribute a noradrenaline signal (Kohonen) that influences downstream neurons to toss out whatever they have learned before and learn again afresh from perception.
The deterioration of the LC in aging in the study was associated with a bias towards "exploitation" of existing resources instead of exploring the environment to find new ones. The extant neuromythographic archetypes explain this result well, as the diminished Kohonen energy emitted by Ajñāna provides muted motivation to throw out everything we know and start understanding anew.
