The new study is part of the journal's special on neuroimaging the chemical senses, with smells evoking extremely powerful and emotional responses in humans. According to Science Daily
, the two researchers, Krusemark and Li, found that when people detect a bad smell, it signals: a possible danger of a decaying object ---associated with disease; or the odor signals the danger of an airborne substance.
As anxiety levels in a person rises, "so does the subjects' ability to discriminate negative odors accurately." A skin conductance shows that anxiety heightens emotional arousal to smell-induced threats. Skin conductance is s a method of measuring the electrical conductance of the skin, which varies with its moisture level, used as an indication of psychological or physiological arousal.
It was found that there is amplified communication between the sensory and emotional areas of the brain. This is in response to negative odors, particularly in anxiety. This increased connectivity could be responsible for the heightened arousal to threats or feeling threatened.
A study by Alexander Toet
found that "orange odor reduces the anticipatory anxiety and improves the mood of patients waiting for scheduled appointments in small dental practices." The study assessed the potential awareness of the presence of an ambient odor on the patient's emotional and mental awareness of pain levels, awareness of the waiting room, mood, and alertness.
The study by Toet found that "further investigations should resolve whether these scents may ultimately reduce the anxiety of patients with higher levels of pain by stimulating their sensory awareness." Meanwhile, the study by Krusemark and Li concluded that, "This enhanced sensory-emotional coupling could serve as a critical mechanism to arouse adequate physiological alertness to potential insults."