TL;DR: All the available evidence points to a great acuity of the olfactory sense in many fish species both in the capability and discriminating odorous chemicals.
TL;DR: The majority of 14 human observers lacking olfactory nerve function detected, by nasal inhalation, over one quarter of 31 chemicals commonly used in Olfactory research, indicating the trigeminal nerve may play an important role in human nasal chemoreception and that effective trigEMinal stimulants may be predictable on physicochemical grounds.
TL;DR: Research on the postnatal development of behavior involving olfaction is reviewed, including investigations of olfactory responses of human neonates and young children, the development of preferences in various mammals, the ontogeny of the fright reaction in fish and amphibia, and the attraction of maternal odors for small mammals.
TL;DR: Antennal olfactory responses to the compounds did not correlate to published data on behavioral responses by the beetles to the compound in both field and laboratory studies, suggesting that the terpene hydrocarbons share some, but not all, of the same receptors.
Abstract: Electroantennograms from males and females ofDendroctonus frontalis andD. brevicomis in response to serial dilutions of the pheromonesexo brevicomin and frontalin and the host terpene hydrocarbons 3-carene and α-pinene show no significant differences in the threshold concentration for response to the compounds for either sex or species. The intensity of response was greater to higher concentrations of the pheromones (10 to >104 μg) than the terpene hydrocarbons, suggesting the presence of more receptors on the antennae for pheromones than terpene hydrocarbons. Antennal olfactory responses to the compounds did not correlate to published data on behavioral responses by the beetles to the compounds in both field and laboratory studies. Adaptation experiments indicated that forD. frontalis, both frontalin andexo brevicomin share the same receptors on the antennae. The results indicated that the terpene hydrocarbons share some, but not all, of the same receptors.
TL;DR: Observed postsurgical rearrangements in the connections of axons in the lateral olfactory tract may explain both the sparing and the deterioration of function in male hamsters.
Abstract: Mating behavior in male hamsters depends on the sense of smell. Thus, complete transection of the lateral olfactory tract in adults eliminates mating. If the cut is made early in life, however, mating is spared. Partial section of the tract in adults does not affect mating, but similar cuts in the neonate lead to impaired mating performance later in life. Observed postsurgical rearrangements in the connections of axons in the lateral olfactory tract may explain both the sparing and the deterioration of function.
TL;DR: The nasal epithelia of two species of bats were quantified with respect to relative surface areas and olfactory epithelial volumes to suggest a developmental design mechanism for an Olfactory bulb in which the number ofOlfactory receptors increases some 450-fold above an initially established ratio of 2:1 between receptors and mitral cells.
Abstract: The nasal epithelia of two species of bats were quantified with respect to relative surface areas and olfactory epithelial volumes. In the macrosmatic Aribeus jamaicensis 55.9% of the nasal cavity surface was covered by olfactory epithelium (232.4 mm2), in contrast to only 28.9% in the microsmatic Myotis lucifugus (36.4 mm2). The roles of the various nasal epithelia have been discussed as they may relate to olfaction, respiration and echolocation. In the olfactory bulbs of both species, the estimated concentration of mitral cells approximated at 2,500/mm2 compared to an olfactory nerve concentration of 5/mm2. In Artibeus, calculated total volume of olfactory epithelium was on the order of 16 times greater than in Myotis, and Artibeus' olfactory bulb diameter was twice as great. These findings, together with previously published surface, volume and physiological relationships, suggest a developmental design mechanism for an olfactory bulb in which the number of olfactory receptors increases some 450-fold above an initially established ratio of 2:1 between receptors and mitral cells. Key governing factors could be requisite mechanical rigidity of the cribriform plate of the ethmoid bone and response thresholds of higher brain centers.
TL;DR: The present results indicate that children with cystic fibrosis display a slight hyposensitivity to odorants, in fact, a taste threshold identical to that of normal children.
TL;DR: The electric response olfactometry representing a cortical evoked so-called twin-potential containing equivalents for trigeminal and olfactory sense activity starts to demonstrate its efficiency and at least a complete test of olfactor function today includes the rhinomanometry for recording ability in nasal odor transport capacity.
Abstract: Firstly the review deals with the olfactometry after discussing the olfactory and trigeminal sensitivity of the sense of smell. The term olfactometry will be newly fixed concerning the present problems of odor analysis. Under clinical aspects the methods of subjective olfactometry are discussed and valued. Olfactory tests basing on registering several psychosomatic reflexes (e.g. cardial and/or respiratory frequencies) cannot be described as "objective". Rather methods are objective which record poststimulatory electrophysiological events at different steps of olfactory pathways. The electric response olfactometry representing a cortical evoked so-called twin-potential containing equivalents for trigeminal and olfactory sense activity starts to demonstrate its efficiency. At least a complete test of olfactory function today includes the rhinomanometry for recording ability in nasal odor transport capacity. In the second part are discussed the olfactory disorders with clinical importance. Air borne disorders are confronted with sensorineural, which again are divided in prebulbar, bulbar, and postbulbar ones so far as possible. Respiratory smell disorders depend on nasal ventilation and occur in nasal deformations, in abnormalities of respiratory pathways, in cases of foreign bodies, mucosal inflammations, tumors, intoxications and allergy. Sensorineural olfactory disorders can be attached to age, to malformations or idiopathic defects, inflammations of the olfactory-neural apparatus, head injuries, brain tumors, metabolic or endocrinological diseases. Furthermore often they are accompanied with neurological and psychiatric diseases or professional and chemical intoxications and/or iatrogenic influences. The poor therapeutical possibilities are demonstrated as far as possible. Finally the experting problems in olfactory disorders are delineated, at which the evidence of objective olfactometry can be distincted.
TL;DR: The somewhat surprising depression of marking among isolated, anosmic males strongly suggests that olfaction is the primary modality for detecting even nonbiological novelty.
TL;DR: An ability for olfactory discrimination between amino acids was suggested from the frequency spectral patterning of the responses in rainbow trout.
TL;DR: The analyses suggest that olfaction in migrating chum salmon is useful in discriminating among various stream waters, and the coding mechanism in the olfactory function is discussed insofar as it is characterized by the spectral patterns of specific responses.
TL;DR: The lateral forebrain bundle (perhaps the major correlative fiber tract for olfactory, visceral and somatic impulses) begins in the striatum and terminates in the ventral thalamus and midbrain tegmentum, thereby effecting voluntary motor responses.
Abstract: This study concerns the morphological description of the nuclear groups and fiber tracts in the olfactory areas in the lateral wall of the hemisphere of the gerbil. The sense of olfaction is assumed to play an important role in the gerbil's behavior (see Vol. 15, Sect. 4). The hippocampal formation, amygdala and corpus striatum are well-developed and differentiated structures in the gerbil. These areas receive either direct or indirect olfactory connections through such pathways as the medial and lateral olfactory tracts. Other fiber tracts such as the anterior commissure, fornix, stria terminalis and the lateral forebrain bundle, carrying somatic and/or visceral fibers, as well, distribute olfactory impulses to numerous areas of the gerbil's brain. The lateral forebrain bundle (perhaps the major correlative fiber tract for olfactory, visceral and somatic impulses) begins in the striatum and terminates in the ventral thalamus and midbrain tegmentum. From there fibers are sent to the spinal cord, thereby effecting voluntary motor responses.
TL;DR: The results point to the role of olfaction in toads as well as their response to lasting olfactory cues in anurans.
Abstract: The influence of olfactory and visual prey stimuli on the feeding behaviour of toads was studied as well as their response to lasting olfactory cues. A further aim was to find simple methods for testing olfactory responsiveness in anurans. Subjects were 8 adult specimens of the European species Bufo calamita (natterjack) kept in captivity one year at least. The results point to the role of olfaction in these animals.