TY - JOUR
T1 - Odour perception following bilateral damage to the olfactory bulbs
T2 - A possible case of blind smell
AU - Zucco, Gesualdo M.
AU - Prior, Massimo
AU - Sartori, Giuseppe
AU - Stevenson, Richard J.
PY - 2013/2
Y1 - 2013/2
N2 - Introduction: Unconsciously detected chemicals may affect human behaviour (. Kirk-Smith et al., 1983; Stern and McClintock, 1998; Zucco et al., 2009), likeability judgements (. Li et al., 2007) and brain activity (. Lorig et al., 1990; Sobel et al., 1999). No studies, however, have investigated blind smell - the hypothetical olfactory counterpart of blindsight (. Weiskrantz et al., 1974). Methods: In this report, free and cued olfactory identification of suprathreshold odorants varying in irritancy (i.e., low or no irritant odours versus irritant odours), and taste identification abilities, were examined in patient MB who had undergone surgery for a meningioma. Post-operative imaging revealed encephalomalacia in the left gyrus rectus, with ablation of the left olfactory bulb and damage to the right, subcortical abnormality on the left near the orbital cortex, and damage to a small section of the right gyrus rectus. Results: On free identification MB, while denying a capacity to smell the odours, still correctly identified some and detected others significantly above chance. In contrast, awareness always accompanied correct detections of irritant odours. Cued odour identification was at chance and no taste impairments were observed. Conclusions: We suggest, tentatively, that MB's unusual pattern of awareness when detecting and identifying odours relative to irritant odours may represent an example of 'blind smell'.
AB - Introduction: Unconsciously detected chemicals may affect human behaviour (. Kirk-Smith et al., 1983; Stern and McClintock, 1998; Zucco et al., 2009), likeability judgements (. Li et al., 2007) and brain activity (. Lorig et al., 1990; Sobel et al., 1999). No studies, however, have investigated blind smell - the hypothetical olfactory counterpart of blindsight (. Weiskrantz et al., 1974). Methods: In this report, free and cued olfactory identification of suprathreshold odorants varying in irritancy (i.e., low or no irritant odours versus irritant odours), and taste identification abilities, were examined in patient MB who had undergone surgery for a meningioma. Post-operative imaging revealed encephalomalacia in the left gyrus rectus, with ablation of the left olfactory bulb and damage to the right, subcortical abnormality on the left near the orbital cortex, and damage to a small section of the right gyrus rectus. Results: On free identification MB, while denying a capacity to smell the odours, still correctly identified some and detected others significantly above chance. In contrast, awareness always accompanied correct detections of irritant odours. Cued odour identification was at chance and no taste impairments were observed. Conclusions: We suggest, tentatively, that MB's unusual pattern of awareness when detecting and identifying odours relative to irritant odours may represent an example of 'blind smell'.
UR - http://www.scopus.com/inward/record.url?scp=84875239319&partnerID=8YFLogxK
U2 - 10.1016/j.cortex.2012.04.002
DO - 10.1016/j.cortex.2012.04.002
M3 - Article
VL - 49
SP - 599
EP - 604
JO - Cortex
JF - Cortex
SN - 0010-9452
IS - 2
ER -