Attitudes toward Everyday Odors for Children with Visual Impairments: A Pilot Study

Abstract

The question of how the processing of stimuli from the external world is organized or reorganized when a sensory modality is altered or missing has been the subject of numerous studies, although the studies have mostly been on tactile and auditory abilities (Hatwell, 2003). In contrast, olfaction has been poorly investigated in people who are visually impaired, despite the increasing evidence that humans have a keen sense of smell (Schaal & Porter, 1991). Odors influence mood; well-being (Ehrlichman & Bastone, 1992); and social interactions, such as the choice of partners (Herz & Inzlicht, 2002). Emotional and social implications of odors go back to the earliest periods of development (Schaal, 1988). Olfaction should thus be considered a significant source of environmental information and emotions in persons with visual impairments. Most, if not all, studies of the relationship between olfaction and blindness aimed to test the intuitive hypothesis of increased sensitivity of the unimpaired senses (for a review, see Ferdenzi, Holley, & Schaal, 2004). The comparison of olfactory detection thresholds in participants with and without visual impairments first led to inconsistent results (Boccuzzi, 1962; Griesbach, 1899). More recent studies that have used more reliable methods found no difference between the two groups in olfactory sensitivity, discrimination, or cued identification (that is, the choice of the name of an odor from among several alternatives) (Diekmann, Walger, & von-Wedel, 1994; Schwenn, Hundorf, Moll, Pitz, & Mann, 2002; Smith, Doty, Burlingame, & McKeown, 1993). Conversely, more ecological perceptual tasks, such as noncued odor identification, revealed better performances by participants with visual impairments (Murphy & Cain, 1986; Rosenbluth, Grossman, & Kaitz, 2000; Wakefield, Homewood, & Taylor, 2004). This advantage was interpreted as reflecting higher attention to olfactory stimuli, resulting in deeper knowledge and the better ability to reactivate associated information. Thus, possible differences in favor of people with visual impairments may be a result more of advantages in attentional strategies than of enhanced sensitivity. This view was advocated by Tilney (1929), who examined Helen Keller: [Her] olfactory sense shows nothing above the normal average.... Her sensory supremacy is entirely in the realm of intellect (pp. 1242, 1254). Outstanding olfactory abilities of individuals with visual impairments have repeatedly been reported in everyday life contexts. For instance, Julia Brace (James, 1890) and an anonymous young boy (Hinds, 1984) were able to sort the freshly washed linen of acquaintances by smell alone; Willetta Huggins was able to identify the color of fabrics according to the odor of the dyes (Gault, 1923). Describing children with visual impairments sniffing out objects, people, or themselves, Hinds (1984) interpreted these frequent behaviors as an unrestrained seeking of information. Odors seem to help build representations of the environment, as Rosenfeld (2001) also suggested. In Rosenfeld's survey, respondents with visual impairments declared more often than their sighted counterparts that odors provide useful information to characterize or identify places and people. These sparse observations stimulated us to investigate olfaction-blindness interactions in everyday settings. The purpose of our study was to conduct a pilot investigation of the self-reported awareness and reactivity to odors of children with visual impairments and sighted children. A questionnaire related to relevant everyday contexts involving food and social cues, as well as the general environment, was used to determine whether, and in which conditions, odors would constitute salient cues for children with visual impairments. METHOD Participants Six boys and two girls with visual impairments, aged 8 to 11, were recruited from a specialized center in Dijon, France (see Table 1 for the characteristics of the participants). …