XVI International Symposium on Olfaction and Taste - ecro

<strong>XVI</strong> <strong>International</strong> <strong>Symposium</strong> on Olfaction and Taste
Poster session I Poster #241
Long-term odor and face recognition as a function of familiarity
Stina Cornell Kärnekull 1 , Fredrik U. Jönsson 1 , Johan Willander 2 , Sikström Sverker 3 and Maria Larsson 1
1Department of Psychology, Stockholm University, Sweden
2Århus University, Denmark
3Cognitive Science (LUCS), Lund University, Sweden
stina.cornell.karnekull@psychology.su.se
This study investigated episodic recognition memory for odors and faces in the long-term as a function of familiarity.
Eighty-three subjects (43 women, 40 men) encoded familiar and unfamiliar odors and faces and memory was assessed at
four occasions; immediate, 4, 16 and 64 days after encoding. The results showed significant forgetting of odors and faces
across time, higher overall recognition memory for faces than for odors, better retention for familiar than unfamiliar
information, and no influence of gender on memory performance. In addition, hit rate performance was positively
associated with naming ability at encoding, although the relationship was much less pronounced for faces than for odors.
Interestingly, the decline in odor memory was primarily driven by an increment in false alarm rates over time. This
observation indicates that episodic retention of olfactory information is susceptible to the passage of time.
This work is supported by the Swedish Research council to ML.
Poster session I Poster #145
Configural perception of a six-odorants mixture in newborn rabbits and human adults
Gérard Coureaud 1 , Charlotte Sinding 1 , Béno Noelle 1 , Adeline Chambault 1 , Thibaut Dosne 1 , Claire Chabanet 1 and
Thierry Thomas-Danguin 1
1 CSGA, CNRS/INRA/UB, Dijon, France
gerard.coureaud@u-bourgogne.fr
Throughout their development, mammals are exposed to complex environments. Odours from the surroundings arise
from mixtures of volatiles, and even when organisms respond to key-odour cues, they respond to cues perceived among
other. Several perceptual interactions may occur over mixture coding and processing (e.g. synergy/masking). Configural
perception is another form of interaction. Unlike analytical perception, based on the perception of the components'
odours, configural processing leads to the perception of a new odour, distinct from the odours of the components (in
humans, the effect is called blending effect). Here, we evaluated the perception of a senary mixture both in human adults
and newborn rabbits using in one hand (human) a sorting task to get odour resemblance results and a 3D-odour-space
representation to illustrate them, and in another hand (rabbit) single-trial conditioning to confer a value to the stimuli and
behavioural testing (sucking response) to quantify their perception. We used a mixture from which emerges (in humans), at
a specific ratio of odorants, a red cordial odour. First, we showed that the mixture is perceived as being different from its
components in both species: human subjects sorted out separately the mixture and its single components; rabbit
neonates did not respond to the mixture after learning one component. Second, this difference in perception appeared for
the red cordial mixture, but not for another mixture of six components: human subjects gathered this other mixture and
some of its components, rabbit pups responded to the mixture. Third, the red cordial mixture was no longer perceived as a
configuration after modification of certain or all the components proportion. Thus, perception of configurations in
relatively complex mixtures appears not systematic but dependent on chemical composition and components proportion.
The modulation of the perception presents overlap between species and between ontogenetic stages.
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