Olfactory Perception Database: Map of Perceptual Similarity

In a space that currently contains 160 odorants, the greatest distance between any two odorants is approx. 183.33 Arbitrary units (AU), and the smallest distance is approx. 0.385 AU.

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Directions: Select two chemicals and press the “is” button to obtain the perceptual distance between them.

Click here to view odor-maps on the rat olfactory bulb
Click here to view links between odors and the receptors that bind them


Note that you can zoom in on any region of the graph by drawing a box. Start at the upper left corner of the region you wish to view in more detail, and drag downwards and to the right. Dragging upwards allows you to zoom out. Clicking on the "fill" button at the upper right brings all data within range.

* Verbal descriptors best fit mixtures made of many different molecules rather than the neat molecules represented here.
* The odor-space computations presented here are described in detail in Khan et al., 2006
* The raw data for the computations is from Dravnieks, 1985
* This applet was built using Ptolemy Ptplot