The smound concept is based on a study done by Daniel Wesson, PhD and Donald Wilson, PhD, researchers at the Nathan S Kline Institute for Psychiatric Research in New York.
The study, which was published in The Journal of Neuroscience, traced extracellular recordings from the olfactory tubercles of anesthetized mice. They found that 65% of single tubercle units responded to odours and 19% responded to auditory tones. When the tubercles were subjected to both odour and tone, 29% displayed supraadditive or suppressive responses. The authors of the study have suggested that this shows some cross-modulation between the two senses.