BACKGROUND For olfaction, several studies have reported near-infrared spectroscopy (NIRS) signal changes in the orbitofrontal cortex (OFC) during odor stimulation. However, the roles of human OFC in olfactory cognition are less well understood. This study was designed to better understand the roles of OFC for olfaction. METHODS Hemodynamic responses for phenyl ethyl alcohol or citral in the O...

The olfactory system provides numerous functions to humans, influencing ingestive behavior, awareness of environmental hazards and social communication. Approximately 1/5 of the general population exhibit an impaired sense of smell. However, in contrast to the many affected, only few patients complain of their impairment. So how important is it for humans to have an intact sense of smell? Or is...

In the philosophy of perception, olfaction is the perennial problem child, presenting a range of difficulties to those seeking to define its proper referents, and its phenomenological content. Here, we argue that many of these difficulties can be resolved by recognizing the object-like representation of odors in the brain, and by postulating that the basic objects of olfaction are best defined ...

The routine test of olfaction need not lead to an ambiguous outcome, a rather widely held notion. A multiple-choice test of odor identification that avoided the difficulty of retrieving odor names yielded excellent resolution among the categories normosmic, hyposmic, and anosmic. The outcome agreed almost perfectly with a more complicated test of threshold and offered much encouragement for the...