<p>In the present thesis, three empirical studies investigate autobiographical odor memory with regard to: (a) whole life-span age distributions, (b) phenomenological experience, (c) semantic processing, and (d) odor imagery. Study I explored potential influences of cue type (words, pictures, odors) on the retrieval of autobiographical memories. The results indicated that odor-evoked events were older than memories evoked by words and pictures. The bump for olfactory evoked information peaked in the first decade of life (<10 years of age), whereas the bump of the word- and picture-evoked age distributions peaked in the second decade (i.e., 11-20 years of age). Also, olfactory evoked events were associated with stronger feelings of being brought back in time. Study II investigated the influence of verbal processing on the retrieval of autobiographical olfactory information. The results revealed that semantic knowledge (i.e., the odor name) affected both the age distribution and phenomenological experience. Also, olfactory memories were associated with a higher emotional arousal. Study III addressed the influences of olfactory imagery on the age distribution and phenomenological experiences. The results showed that events evoked by odor imagery were older than memories evoked by words. No differences in phenomenological experiences were found between the two cue conditions. Based on these findings, it is suggested that (a) memories evoked by olfactory information are older than memories evoked by verbal and visual information, (b) odor memories are more emotional and associated with stronger feelings of being brought back in time, (c) knowledge of an odor’s name produces a shift from a more perceptually to a more conceptually driven retrieval, and that (d) imagined odor cues mimic the age distribution of events evoked by real odors. Overall, the results suggest that memories triggered by the olfactory sensory system are different from memories evoked by verbal or visual information.</p>

<p>The notion that humans have specialized chemicals used for communication between conspecifics, so-called pheromones, has attracted much attention and discussion. This thesis demonstrates in four separate studies that a human endogenous steroidal compound that is abundant in male sweat, androstadienone, affects women in several ways that differ to that of common odors. Specifically, androstadienone was found in Study I to have unique psychophysical characteristics in that the sensitivity distribution of the odor is bimodal with a smaller subpopulation consisting of highly sensitive individuals. Trigeminal mediation of this bimodality was experimentally excluded. Moreover, Study II demonstrated that women’s cortical activation of androstadienone exposure was found to differ to that of common odorants in that androstadienone was processed faster than two perceptually similar control odors. It was further demonstrated that a non-detectable amount of androstadienone can reliably modulate both mood and physiology in women (Study III & IV); in particular mood referring to attention processes. Study IV showed that androstadienone-induced mood changes in heterosexual women were only evident when the experiment was administered by an experimenter of different sex. The combined results from these studies suggest that androstadienone serves as a human modulator pheromone that guides our behavior by inducing subtle changes in higher cognitive processes in relation to the ecological context at hand. A new definition of human pheromones is proposed and discussed in relation to the obtained results.</p>

Ultra high temperature (UHT) processing can extend shelf life of milk to several months without refrigeration, which is more convenient and energy saving than pasteurized milk. However, the poor acceptance caused by "cooked" flavors limits its marketing growth, especially in United States. Ohmic heating, which has a more uniform and rapid heating than conventional UHT process, may minimized the flavor change during the thermal treatment. Flavor composition between Ohmic heated UHT milk and other traditionally processed UHT milk (direct steam injection and indirect plate heating) during 36 weeks storage were investigated in this study. A total of 20 volatile compounds were analyzed based on their importance to UHT milk as well as their representation to different chemical classes including sulfur-containing compounds, ketones, lactones, aldehydes and others. Dimethyl sulfide (DMS) and methyl ketones were significant different among three types of UHT heated milk. δ-lactones showed higher amount in Ohmic heating after stored for four weeks, which might generate creamy, fruity intermediate aroma. Other compounds showed no significant difference among three heating processes. Aroma recombination test revealed that the overall aroma of the ultra pasteurized (UP) milk could be mimicked by recombining 15 important reference odorants in the same concentrations as they occurred in the UHT milk using commercial pasteurized milk as the matrix. / Graduation date: 2012

The notion that humans have specialized chemicals used for communication between conspecifics, so-called pheromones, has attracted much attention and discussion. This thesis demonstrates in four separate studies that a human endogenous steroidal compound that is abundant in male sweat, androstadienone, affects women in several ways that differ to that of common odors. Specifically, androstadienone was found in Study I to have unique psychophysical characteristics in that the sensitivity distribution of the odor is bimodal with a smaller subpopulation consisting of highly sensitive individuals. Trigeminal mediation of this bimodality was experimentally excluded. Moreover, Study II demonstrated that women’s cortical activation of androstadienone exposure was found to differ to that of common odorants in that androstadienone was processed faster than two perceptually similar control odors. It was further demonstrated that a non-detectable amount of androstadienone can reliably modulate both mood and physiology in women (Study III &amp; IV); in particular mood referring to attention processes. Study IV showed that androstadienone-induced mood changes in heterosexual women were only evident when the experiment was administered by an experimenter of different sex. The combined results from these studies suggest that androstadienone serves as a human modulator pheromone that guides our behavior by inducing subtle changes in higher cognitive processes in relation to the ecological context at hand. A new definition of human pheromones is proposed and discussed in relation to the obtained results.

In the present thesis, three empirical studies investigate autobiographical odor memory with regard to: (a) whole life-span age distributions, (b) phenomenological experience, (c) semantic processing, and (d) odor imagery. Study I explored potential influences of cue type (words, pictures, odors) on the retrieval of autobiographical memories. The results indicated that odor-evoked events were older than memories evoked by words and pictures. The bump for olfactory evoked information peaked in the first decade of life (&lt;10 years of age), whereas the bump of the word- and picture-evoked age distributions peaked in the second decade (i.e., 11-20 years of age). Also, olfactory evoked events were associated with stronger feelings of being brought back in time. Study II investigated the influence of verbal processing on the retrieval of autobiographical olfactory information. The results revealed that semantic knowledge (i.e., the odor name) affected both the age distribution and phenomenological experience. Also, olfactory memories were associated with a higher emotional arousal. Study III addressed the influences of olfactory imagery on the age distribution and phenomenological experiences. The results showed that events evoked by odor imagery were older than memories evoked by words. No differences in phenomenological experiences were found between the two cue conditions. Based on these findings, it is suggested that (a) memories evoked by olfactory information are older than memories evoked by verbal and visual information, (b) odor memories are more emotional and associated with stronger feelings of being brought back in time, (c) knowledge of an odor’s name produces a shift from a more perceptually to a more conceptually driven retrieval, and that (d) imagined odor cues mimic the age distribution of events evoked by real odors. Overall, the results suggest that memories triggered by the olfactory sensory system are different from memories evoked by verbal or visual information.

The sense of smell plays an important role in regulating the behavior of Asian elephants but until now, no behavioral test to systematically assess the olfactory capabilities of this species existed. Using a voluntary, food-rewarded two-alternative operant conditioning procedure, three female Asian elephants were successfully taught to discriminate between rewarded and unrewarded odors and also succeeded in intramodal stimulus transfer tasks in which either the rewarded odor, or the unrewarded odor, or both odors were exchanged simultaneously for new odors. The animals readily mastered the initial task within only 120 stimulus contacts, demonstrating rapid olfactory learning and performing at least as good as rodents and dogs and even better than other species, including nonhuman primates, tested in similar studies before. When presented with pairs of structurally related odorants, the discrimination performance of the elephants decreased with increasing structural similarity of the odorants, but the animals still significantly discriminated between aliphatic acetic esters even when they only differed by one carbon chain length. The elephants also demonstrated an excellent long-term odor memory and successfully remembered the reward value of previously learned odor stimuli after two, four, eight and even 16 weeks of recess in testing. The paradigm developed and applied in the present study proved to be useful to assess the olfactory capabilities in Asian elephants.

Magistrinio darbo tikslas – įgyvendinti, graužikų biologinio, aplinkos žymėjimo kvapais ir navigacijos, proceso modelį robotikos srityje. Graužikai aplinkoje orientuojasi analizuodami informaciją gautą iš skirtingų penkių jutimo organų. Regėjimas padeda suvokti aplinkos erdvę, reljefą, atstumus iki objektų. Klausa, suteikia informaciją apie aplink esančius garso šaltinius, besiartinančius gyvūnus. Lytėjimas, padeda nustatyti objekto paviršiaus savybes: karštas ar šaltas, drėgnas ar sausas, minkštas ar kietas. Uoslė ir skonio receptoriai naudojami nustatyti maisto šaltiniui ar teritorijos riboms. Realiame biologiniame pasaulyje gyvūnai gali lengvai analizuoti informaciją gautą iš skirtingų jutimo organų ir ją derinti erdvinės navigacijos procese. Dirbtinėje sistemoje šie duomenys yra gaunami iš sensorių pasižyminčių skirtingomis savybėmis ir techniniais parametrais. Projekto tikslas - išspręsti robotikos uždavinį: tikslo paieškos navigacija naudojant aplinkos žymėjimą. Sukurta sistema imituoja graužiko erdvinės navigacijos procesą naudojant du skirtingus jutimo sensorius: dirbtinę regą ir dirbtinę uoslę. Projekte pristatoma sukurta sistema ir realizuoti erdvinės navigacijos algoritmai naudojantys vaizdinę ir kvapo informaciją. Aprašoma eksperimento vykdymo metodika ir priemonės. / The aim of the master thesis is to implement, rodent’s biological, goal directed navigation based on self-marking process in robotics. Rodents in environment navigate using analyzed information that gets from five different senses. Seeing helps to realize environment’s space, relief, distance from the objects. Hearing sense gives information about sound position of sound sources or other animals. Touch sense helps to determine properties of the surface: is it cold or hot, dry or wet, soft or hard. Olfactory and flavor receptors are used to determine food source or territory range. In real biological world animals could easily analyze and combine information from different sense receptors in spatial navigation process. In artificial system this data we are getting from different type and characteristics sensors. The main aim of this project is to solve robotic task: goal directed navigation based on self -marking method. Created system simulates rodent’s spatial navigation process where in two sensors are used: artificial eyes and artificial nose. This project presents created system and implemented spatial navigation algorithms which are using video and odor tracking based information. The methodology and tools used in experiment are described in this paper.

La littérature décrit certains phénomènes de réorganisation physiologique et fonctionnelle dans le cerveau des aveugles de naissance, notamment en ce qui a trait au traitement de l’information tactile et auditive. Cependant, le système olfactif des aveugles n’a reçu que très peu d’attention de la part des chercheurs. Le but de cette étude est donc de comprendre comment les aveugles traitent l’information olfactive au niveau comportemental et d’investiguer les substrats neuronaux impliqués dans ce processus. Puisque, en règle générale, les aveugles utilisent leurs sens résiduels de façon compensatoire et que le système olfactif est extrêmement plastique, des changements au niveau de l’organisation anatomo-fonctionnelle pourraient en résulter. Par le biais de méthodes psychophysiques et d’imagerie cérébrale (Imagerie par Résonance Magnétique fonctionnelle-IRMf), nous avons investigué les substrats anatomo-fonctionnels sollicités par des stimuli olfactifs. Nous avons trouvé que les aveugles ont un seuil de détection plus bas que les voyants, mais que leur capacité à discriminer et identifier des odeurs est similaire au groupe contrôle. Ils ont aussi plus conscience de l’environnement olfactif. Les résultats d’imagerie révèlent un signal BOLD plus intense dans le cortex orbitofrontal droit, le thalamus, l’hippocampe droit et le cortex occipital lors de l’exécution d’une tâche de détection d’odeur. Nous concluons que les individus aveugles se fient d’avantage à leur sens de l’odorat que les voyants afin d’évoluer dans leur environnement physique et social. Cette étude démontre pour la première fois que le cortex visuel des aveugles peut être recruté par des stimuli olfactifs, ce qui prouve que cette région assume des fonctions multimodales. / It is generally acknowledged that people blind from birth develop supra-normal sensory abilities in order to compensate for their visual deficit. While extensive research has been done on the somatosensory and auditory modalities of the blind, information about their sense of smell remains scant. The goal of this study was therefore to understand olfactory processing in the blind at the behavioral and the neuroanatomical levels. Since blind individuals use their remaining senses in a compensatory way to assess their environment and since the olfactory system is highly plastic, it is likely to be susceptible to changes similar to those observed for tactile and auditory modalities. We used psychophysical testing and functional magnetic resonance imaging (fMRI) to investigate the neuronal substrates responsible for odor processing. Our data showed that blind subjects had a lower odor detection threshold compared to the sighted. However, no group differences were found for odor discrimination and odor identification. Interestingly, the OAS revealed that blind participants scored higher for odor awareness. Our fMRI data revealed stronger BOLD responses in the right lateral orbitofrontal cortex, bilateral medio-dorsal thalamus, right hippocampus and left occipital cortex in the blind participants during an odor detection task. We conclude that blind subjects rely more on their sense of smell than the sighted in order to assess their environment and to recognize places and people. This is the first demonstration that the visual cortex of the blind can also be recruited by odorants, thus adding new evidence to its multimodal function.

Thesis (M.S.)--Miami University, Dept. of Zoology, 2005. / Title from first page of PDF document. Includes bibliographical references (p. 31-35).

Thesis (M.A.)--University of Wisconsin, 1949. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 157-159).