Nailed it.

Numismatist, 1904

Wilhelm Hammershøi

Cheers

Vibration theory of olfaction - Wikipedia https://share.google/7hCygjlZ1iT4p3nDu

The vibration theory of smell proposes that a molecule's smell character is due to its vibrational frequency in the infrared range. This controversial theory is an alternative to the more widely accepted docking theory of olfaction (formerly termed the shape theory of olfaction), which proposes that a molecule's smell character is due to a range of weak non-covalent interactions between its protein odorant receptor (found in the nasal epithelium), such as electrostatic and Van der Waals interactions as well as H-bonding, dipole attraction, pi-stacking, metal ion, Cation–pi interaction, and hydrophobic effects, in addition to the molecule's conformation

The vibration theory of smell proposes that the distinct odor of a molecule is determined by its unique vibrational frequencies, an idea that sometimes involves quantum mechanics

Although olfaction is generally assumed to play a minor role in humans compared to vision or audition, it is also commonly accepted that odors have a rather unique status for eliciting memories. Indeed, one of the most striking features of odor memory in humans resides in the amazing power of odors to vividly trigger the evocation of autobiographical experiences. This property has been referred to as the “Proust phenomenon” by some authors (Chu and Downes 2000, 2002) because of the well-known literary anecdote reported by Proust (1919) at the beginning of his novel, Swann’s Way, wherein the flavor of a madeleine cake dipped into a cup of tea unwillingly caused the remembrance of an old detailed memory.

“The memory suddenly appears before my mind. The taste was that of the little piece of madeleine which on Sunday mornings at Combray (because on those mornings I did not go out before church-time) my aunt Leonie used to give to me, dipping it first in her own cup of real or lime-flower tea’, leading him to the conclusion that ’When from a long-distant past nothing subsists … the smell and taste of things remain poised for a long time … and bear unfaltering, in the tiny and almost impalpable drop of their essence, the vast structure of recollection.”

A number of psychological studies have experimentally investigated the so-called Proust phenomenon in human subjects. Different works have shown that odor-cued memories are more emotional than memories triggered by visual or verbal

Sense of smell
Memories
Destruction of the hippocampus/cortex/amygdala

Taken together, these studies suggest that human olfaction is unique in its ability to cue the emotional aspects of autobiographical memory, including experiences formed early in life. In animals, memory for environmental odors plays a vital role because it regulates many behaviors that are crucial for their survival.

**autobiographical memory

The Lady and the Unicorn, a Flemish tapestry depicting the sense of smell, 1484–1500. Musée national du Moyen Âge, Paris

Human amygdala activations during nasal chemoreception - ScienceDirect https://share.google/w3hh9AQK3hxHjuGa0

This review serves as a comprehensive discussion of chemosensory stimulation of the amygdala in healthy humans. Following an introduction of the neuroanatomy of chemosensory processing in primary and secondary olfactory structures, functional resonance magnetic imaging and positron imaging tomography studies are systematically categorized based on valence of stimuli, stimulus concentration, and paradigm-dependent amygdala activation. The amygdala shows patterns of lateralization due to stimulus valence. 

Human amygdala activations during nasal chemoreception