Odor

Distribution by Scientific Domains

Kinds of Odor

  • male odor
  • rancid odor

  • Terms modified by Odor

  • odor character
  • odor characteristic
  • odor cue
  • odor discrimination
  • odor identification
  • odor intensity
  • odor perception
  • odor threshold
  • odor value

  • Selected Abstracts


    SIMULATED MICROGRAVITY [BED REST] HAS LITTLE INFLUENCE ON TASTE, ODOR OR TRIGEMINAL SENSITIVITY

    JOURNAL OF SENSORY STUDIES, Issue 1 2001
    ZATA M. VICKERS
    ABSTRACT Anecdotal evidence suggests that astronauts' perceptions of foods in space flight may differ from their perceptions of the same foods on Earth. Fluid shifts toward the head experienced in space may alter the astronauts' sensitivity to odors and tastes, producing altered perceptions. Our objective was to determine whether head-down bed rest, which produces similar fluid shifts, would produce changes in sensitivity to taste, odor or trigeminal sensations. Six subjects were tested three times prior to bed rest, three times during bed rest and two times after bed rest to determine their threshold sensitivity to the odors isoamylbutyrate and menthone, the tastants sucrose, sodium chloride, citric acid, quinine and monosodium glutamate, and to capsaicin. Thresholds were measured using a modified staircase procedure. Self-reported congestion was also recorded at each test time. Thresholds for monosodium glutamate where slightly higher during bed rest. None of the other thresholds were altered by bed rest. [source]


    ALGAL-RELATED TASTES AND ODORS IN PHOENIX WATER SUPPLY: PRELIMINARY REPORT

    JOURNAL OF PHYCOLOGY, Issue 2000
    Q. Hu
    Frequent episodes of algal-related tastes and odors (T & O) in drinking waters in metropolitan Phoenix, Arizona prompted initiation of a three-year project in July 1999 to investigate the occurrence of T & O metabolites and to develop a comprehensive management strategy to reduce the problems in drinking water supplies in arid environments. Two metabolites, 2-methylisoborneol (MIB) and geosmin, have been identified as compounds responsible for the earthy-musty tastes and odors in water supplies. Both were detected in the water supply system, including source rivers, reservoirs, canal delivery system and water treatment plants. Higher concentrations of MIB and geosmin occurred in distribution canals than in the upstream reservoirs indicating that significant production of the T & O compounds occurs within the canal system. A baseline-monitoring program has been established for the complex water supply system, with special emphasis on the canal system. Efforts are underway to investigate possible correlations between physical/chemical parameters, algal composition and biomass, with the occurrence of MIB and geosmin. In addition, several physical and chemical treatments are planned for the canal system to reduce algal growth and related MIB and geosmin concentrations. [source]


    A Case of Foul Genital Odor Treated with Botulinum Toxin A

    DERMATOLOGIC SURGERY, Issue 9 2004
    Jae-Bong Lee MD
    Background. Genital odor is an uncommon condition characterized by an offensive and malodorous smell in the genital area. Although the etiology of foul genital odor is multifactorial, an important cause is sweat secretion and decomposition of sweat components by bacteria. Different methods are effective in reducing body odor secondary to bromhidrosis. Conservative methods only act for a short period of time, and more invasive surgical methods carry risk of complications or are inapplicable for the genital region. Methods. A patient with localized foul odor in the genital hair bearing area was treated with botulinum toxin A. Results. Botulinum toxin A was effective in creating an odorless and anhydrous response in the genital region, and no major adverse effects were noted during a follow-up of 9 months after injection. Conclusion. Local injection of botulinum toxin A appears to be a useful treatment for foul genital odor related to sweat glands activity. [source]


    Odor processing in multiple chemical sensitivity

    HUMAN BRAIN MAPPING, Issue 3 2007
    Lena Hillert
    Abstract Multiple chemical sensitivity (MCS) is characterized by somatic distress upon exposure to odors. As in other idiopathic environmental intolerances, the mechanisms behind the reported hypersensitivity are unknown. Using the advantage of the well-defined trigger (odor), we investigated whether subjects with MCS could have an increased odor-signal response in the odor-processing neuronal circuits. Positron emission tomography (PET) activation studies with several different odorants were carried out in 12 MCS females and 12 female controls. Activation was defined as a significant increase in regional cerebral blood flow (rCBF) during smelling of the respective odorant compared to smelling of odorless air. The study also included online measurements of respiratory frequency and amplitude and heart rate variations by recording of R wave intervals (RR) on the surface electrocardiogram. The MCS subjects activated odor-processing brain regions less than controls, despite the reported, and physiologically indicated (decreased RR interval) distress. In parallel, they showed an odorant-related increase in activation of the anterior cingulate cortex and cuneus-precuneus. Notably, the baseline rCBF was normal. Thus, the abnormal patterns were observed only in response to odor signals. Subjects with MCS process odors differently from controls, however, without signs of neuronal sensitization. One possible explanation for the observed pattern of activation in MCS is a top-down regulation of odor-response via cingulate cortex. Hum. Brain Mapp, 2007. © 2006 Wiley-Liss, Inc. [source]


    Cognitive and Physiological Determinants of Symptom Perception and Interpretation

    JOURNAL OF APPLIED BIOBEHAVIORAL RESEARCH, Issue 1 2008
    Motohiro Nakajima
    The purpose of the current study was to test the aspects of MacGregor and Fleming's model of symptom reporting and illness interpretation. Participants were randomly assigned to cognitive cue (Chemical or No Chemical), sensory cue (Odor or No Odor), and somatic arousal (Exercise or No Exercise) conditions. The findings suggested that although somatic arousal primarily determines whether one experiences symptoms, and expectations,or one's mental model,determine the nature of the attribution regarding the cause of the symptoms, it appears that both the attribution about the cause of the symptoms and the amount of somatic arousal experienced combine to produce the intensity of negative symptoms. [source]


    EFFECTIVENESS OF CHLORINE AND NISIN-EDTA TREATMENTS OF WHOLE MELONS AND FRESH-CUT PIECES FOR REDUCING NATIVE MICROFLORA AND EXTENDING SHELF-LIFE,

    JOURNAL OF FOOD SAFETY, Issue 4 2002
    DIKE O. UKUKU
    ABSTRACT Efficacy of nisin-EDTA treatments as a sanitizing treatment for reducing native microflora of whole melons and extending shelf-life of fresh-cut pieces was compared to chlorine treatments. Whole cantaloupe and honeydew melons were washed with water, nisin (10 ,g/mL)-EDTA (0.02 M), or 200 ppm chlorine for 5 min at , 20C before fresh-cut preparation and storage at 5C for 15 days with periodic microbiological sampling. In addition, some fresh-cut pieces were washed with 10 ,g/mL nisin-EDTA or 50 ppm chlorine for 1 min before storage. Changes in appearance, odor, overall acceptability and the shelf-life of the minimally processed fresh-cut melons were investigated. Preliminary studies indicated that water washes, EDTA (0.002 to 0.2 M) or nisin (5 to 10 ,g/mL) were not effective in reducing the microflora of whole melon when used individually. Nisin-EDTA and chlorine treatments were significantly (P < 0.05) more effective in reducing native microflora than water washes. Nisin-EDTA treatments were significantly (P < 0.05) more effective than chlorine in reducing populations of yeast and mold and Pseudomonas spp. on whole melon surfaces but were not as effective as chlorine treatments for reducing aerobic mesophilic bacteria, lactic acid bacteria and total gram-negative bacteria. Microbial contaminants on fresh-cut pieces washed with 50 ppm chlorine or nisin-EDTA were further reduced. However, microbial populations increased throughout refrigerated storage irrespective of treatments. Odor, appearance, and overall acceptability ratings for cantaloupe and honeydew fresh-cut pieces treated with nisin-EDTA or chlorine were not significantly (P > 0.05) different from each other throughout the storage period (15 to 21 days). However, both treatments led to significantly (P < 0.05) improved ratings compared to the controls for the fresh-cut pieces at 9 to 12 days of storage and thereafter. The results of this study suggest that treatments with nisin-EDTA before and after fresh-cut processing would improve the quality and extend the shelf-life of fresh-cut melon. [source]


    Effect of Aging Time on Volatile Compounds, Odor, and Flavor of Cooked Beef from Pirenaica and Friesian Bulls and Heifers

    JOURNAL OF FOOD SCIENCE, Issue 3 2002
    C. Gorraiz
    ABSTRACT: Volatile compounds, odor, and flavor produced by beef from bulls and heifers of the Pirenaica and Friesian breeds were studied during 7 d of aging. The Friesian breed beef had stronger fatty flavor and aftertaste than the Pirenaica, as well as differences in the content of several volatile compounds. Bull beef had stronger liver-like odor and flavor, and bloody flavor that were related to a higher 2-propanone content, while beef from heifers had stronger characteristic flavor. Aging of meat increased characteristic flavor and aftertaste. Ethanal showed a positive correlation with livery flavor and a negative correlation with the characteristic odor. The hexane seems to contribute to fatty flavor, 2-propanone was related to livery and bloody notes, and 2,2,4,6,6-pentamethylheptane to characteristic flavor. [source]


    Ontogeny of the Enhanced Fetal-Ethanol-Induced Behavioral and Neurophysiologic Olfactory Response to Ethanol Odor

    ALCOHOLISM, Issue 2 2010
    Amber M. Eade
    Background:, Studies report a fundamental relationship between chemosensory function and the responsiveness to ethanol, its component orosensory qualities, and its odor as a consequence of fetal ethanol exposure. Regarding odor, fetal exposed rats display enhanced olfactory neural and behavioral responses to ethanol odor at postnatal (P) day 15. Although these consequences are absent in adults (P90), the behavioral effect has been shown to persist into adolescence (P37). Given the developmental timing of these observations, we explored the decay in the response to ethanol odor by examining ages between P37 and young adulthood. Moreover, we sought to determine whether the P15 neurophysiologic effect persists, at least, to P40. Methods:, Behavioral and olfactory epithelial (OE) responses of fetal ethanol exposed and control rats were tested at P40, P50, P60, or P70. Whole-body plethysmography was used to quantify each animal's innate behavioral response to ethanol odor. We then mapped the odorant-induced activity across the OE in response to different odorants, including ethanol, using optical recording methods. Results:, Relative to controls, ethanol exposed animals showed an enhanced behavioral response to ethanol odor that, while significant at each age, decreased in magnitude. These results, in conjunction with previous findings, permitted the development of an ontologic odor response model of fetal exposure. The fitted model exemplifies that odor-mediated effects exist at birth, peak in adolescence and then decline, becoming absent by P90. There was no evidence of an effect on the odor response of the OE at any age tested. Conclusions:, Fetal exposure yields an enhanced behavioral response to ethanol odor that peaks in adolescence and wanes through young adulthood. This occurs absent an enhanced response of the OE. This latter finding suggests that by P40 the OE returns to an ethanol "neutral" status and that central mechanisms, such as ethanol-induced alterations in olfactory bulb circuitry, underlie the enhanced behavioral response. Our study provides a more comprehensive understanding of the ontogeny of fetal-ethanol-induced olfactory functional plasticity and the behavioral response to ethanol odor. [source]


    SENSORY APPROACH TO MEASURE FRAGRANCE INTENSITY ON THE SKIN

    JOURNAL OF SENSORY STUDIES, Issue 6 2009
    CLAUDIA SILVA CORTEZ-PEREIRA
    ABSTRACT Sensory analysis is a precise and descriptive measuring technique to quantify human responses to stimuli. Odor, one of these stimuli, is basically the result of the interaction between a chemical stimulus and the olfactory receptor system, which can be described using a number of different dimensions and measures through different sensory tests: threshold, intensity and quality. To measure fragrance performance on the skin, these parameters are very important, but the main attribute to be evaluated is substantivity, thus the importance of the sensory scale chosen to measure perception, discriminate different intensities and determine the substantivity of the fragrance. Some studies comparing the labeled magnitude scale (LMS) with other magnitude scales and their derivations showed that the use of the LMS scale to measure fragrance intensity could semantically understand the intensity of the stimulus. Tests using this scale confirmed the applicability and efficiency of the LMS. PRACTICAL APPLICATIONS The objective of this article is to review the techniques used to measure odor and fragrance intensities applied on the skin. The review shows general sensory techniques and their goals, the newest olfactory mechanism and its contribution to sensory evaluation and which attributes should be considered to measure odor. Substantivity/retentivity or longevity can be regarded as the most important attributes if you want to measure fragrance performance on the skin. Past studies showed different scales tested to measure odor, and some of them demonstrated that the labeled magnitude scale is very suitable to measure fragrance on the skin. [source]


    EFFECT OF FREEZING AND FROZEN STORAGE ON THE SENSORIAL CHARACTERISTICS OF LOS PEDROCHES, A SPANISH EWE CHEESE

    JOURNAL OF SENSORY STUDIES, Issue 3 2000
    L. TEJADA
    ABSTRACT The aim of the present work was to study the sensorial characteristics of Los Pedroches cheese after freezing, monitoring the effects of the speed and time of frozen storage. Changes were observed in the hardness, creaminess and eyes of cheeses after 3-months frozen storage. The paste hardened, becoming less creamy, and the number and size of the eyes decreased substantially. However, these attributes remained unchanged during storage periods of up to 9 months. Odor, flavor intensity, acidity and grainy were modified as a consequence of frozen storage. The speed of the freezing process only affected the grainy of the cheese; this was greater in slowly-frozen cheeses. [source]


    Physico-Mechanical Properties, Odor and VOC Emission of Bio-Flour-Filled Poly(propylene) Bio-Composites with Different Volcanic Pozzolan Contents

    MACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2006
    Hee-Soo Kim
    Abstract Summary: This study investigated the physico-mechanical properties, odor and VOC emission of bio-flour filled PP bio-composites with different pozzolan contents. On increasing the pozzolan content, the tensile and flexural strengths of the bio-composites were not significantly changed, whereas the impact strength and water absorption increased slightly and the odor intensity decreased due to the absorption of thermal degradation gases of PP and bio-flour at the pore surface of the pozzolan. The VOC emission of the bio-composites, analyzed by GC-MSD, was mainly due to PP oxidation and the thermal degradation of bio-flour during the extrusion process at high manufacturing temperatures. With increased pozzolan content, other organic compounds of the bio-composites were not significantly changed, but the toluene emission of the bio-composites was decreased. SEM and SEM/EDX mapping techniques were employed to investigate the porous form and the pozzolan distribution in the bio-composites. From these results, we concluded that the addition of pozzolan in the bio-composites was an effective method for reducing their odor and VOC emission without any reduction in mechanical properties. SEM micrograph of pozzolan (10,000×). [source]


    Development of individually distinct recognition cues

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2006
    Jill M. Mateo
    Abstract Despite extensive research on the functions of kin recognition, little is known about ontogenetic changes in the cues mediating such recognition. In Belding's ground squirrels, Spermophilus beldingi, secretions from oral glands are both individually distinct and kin distinct, and function in social recognition across many contexts. Behavioral studies of recognition and kin preferences suggest that these cues may change across development, particularly around the time of weaning and emergence from natal burrows (around 25 days of age). I used an habituation-discrimination task with captive S. beldingi, presenting subjects with odors collected from a pair of pups at several ages across early development. I found that at 21 days of age, but not at 7 or 14, young produce detectable odors. Odors are not individually distinct, however, until 28 days of age, after young have emerged from their burrows and begun foraging. In addition, an individual's odor continues to develop after emergence: odors produced by an individual at 20 and 40 days of age are perceived as dissimilar, yet odors produced at 28 and 40 days are treated as similar. Developmental changes in odors provide a proximate explanation for why S. beldingi littermate preferences are not consolidated until after natal emergence, and demonstrate that conspecifics must update their recognition templates as young develop. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 508,519, 2006. [source]


    Oxytocin and estrogen receptor , and , knockout mice provide discriminably different odor cues in behavioral assays

    GENES, BRAIN AND BEHAVIOR, Issue 4 2004
    M. Kavaliers
    Social behavior involves both the recognition and production of social cues. Mice with selective deletion (knockout) of either the gene for oxytocin (OT) or genes for the estrogen receptor (ER) -, or -, display impaired social recognition. In this study we demonstrate that these gene knockout mice also provide discriminably different social stimuli in behavioral assays. In an odor choice test, which is a measure of social interest and discrimination, outbred female Swiss-Webster mice discriminated the urine odors of male knockouts (KO: OTKO, ,ERKO, ,ERKO) from the odors of their wildtype littermates (WT: OTWT, ,ERWT, ,ERWT). Females showed marked initial choices of the urine odors of OTWT and ,ERWT males over those of OTKO and ,ERKO males, and ,ERKO males over ,ERWT males. The odors of OTKO and ,ERKO males also induced aversive, analgesic responses, with the odors of WTs having no significant effects. Odors of both the ,ERWT and ,ERKO males induced aversive, analgesic responses, with the odors of the WT inducing significantly greater analgesia. The odors of restraint stressed WT and KO males also elicited analgesia with, again, females displaying significantly greater responses to the odors of stressed OTKO and ,ERKO males than their WTs, and significantly lower analgesia to the odors of stressed ,ERKO than ,ERWT males. These findings show that the KO mice are discriminated from their WTs on the basis of odor and that the various KOs differ in the relative attractiveness/aversiveness of their odors. Therefore, in behavioral assays one causal route by which gene inactivation alters the social behavior of knockout mice may be mediated through the partners' modified responses to their odors. [source]


    Ontogenetic differences in the expression of conditioned visual aversions

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2003
    Joyce A. Jagielo
    Abstract We examined ontogenetic differences in the expression of conditioned visual aversions. Sprague-Dawley-derived rats, 16 or 21 days of age, were conditioned with either an element (brightness) or compound (brightness/odor) CS+ and tested for their aversion to the common element (brightness). Aversions to the brightness cue were assessed by either a traditional test of preference between the CS+ brightness and a contrasting brightness or by assessment of freezing in the presence of either brightness cue. The results indicated that strength of conditioning as well as the expression of overshadowing/potentiation was dependent on the age of the animal and on the technique used to assess conditioning. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 123,130, 2003 [source]


    PERCEPTION OF CHEESE: A COMPARISON OF QUALITY SCORING, DESCRIPTIVE ANALYSIS AND CONSUMER RESPONSES

    JOURNAL OF FOOD QUALITY, Issue 4 2005
    MARGRETHE HERSLETH
    ABSTRACT The main objective of this study was to study perception of cheeses by comparing quality scores from expert assessors, descriptive profiling data from selected assessors and consumer responses. Twelve cheeses were evaluated by expert assessors and profiled by selected assessors. Five cheeses were selected for consumer testing and rated for hedonic liking, plus flavor intensity and degree of soft/firm texture. Analysis of variance and multivariate analyses of the data showed that the expert assessors scores for consistency, flavor and overall quality correlated positively with descriptive profiling attributes as mature flavor/odor, firmness, graininess and dryness of the cheeses. Preference mapping showed an even distribution of the consumers in the sensory map, which indicated different sensory segments. Some consumers preferred a firm cheese with a mild, mature flavor and others preferred a doughy cheese with more acid, fermented flavor. The expert assessors represented the preferences of the first group in their scoring procedure. [source]


    Making Scents: Improvement of Olfactory Profile after Botulinum Toxin-A Treatment in Healthy Individuals

    DERMATOLOGIC SURGERY, Issue 2007
    MARC HECKMANN MD
    BACKGROUND The axilla is particularly associated with body odor and putative pheromone production in humans. Although botulinum toxin type A (BT-A) is injected increasingly into the axillary skin to stop excessive sweating, its potential to control body odor is largely unexplored. OBJECTIVE The objective was to measure the impact of BT-A on human axillary odor in an objective and reproducible fashion. METHODS This study was a randomized, double-blind, placebo-controlled trial with 51 healthy volunteers receiving 50 U of BOTOX (Allergan, Inc.) in one axilla and placebo in the other. Odor quality was assessed by treated subjects (questionnaire) as well as by independent raters who were exposed to blinded T-shirt samples. RESULTS No major side effects occurred, and no subject withdrew from the study for medical reasons. Samples from the BT-A,treated side smelled less intense (p<.001) and better (p<.001) according to self-assessments. Likewise, independent raters found the BT-A,treated samples to smell less intense and better (p<.001). They preferred "to work together with the respective person" and found the odor "more erotic" (p<.001). CONCLUSION Side-by-side comparison of odor samples (T-shirt sniff test) by independent raters showed that axillary odor in healthy individuals is significantly more appealing after BT-A injection. [source]


    A Case of Foul Genital Odor Treated with Botulinum Toxin A

    DERMATOLOGIC SURGERY, Issue 9 2004
    Jae-Bong Lee MD
    Background. Genital odor is an uncommon condition characterized by an offensive and malodorous smell in the genital area. Although the etiology of foul genital odor is multifactorial, an important cause is sweat secretion and decomposition of sweat components by bacteria. Different methods are effective in reducing body odor secondary to bromhidrosis. Conservative methods only act for a short period of time, and more invasive surgical methods carry risk of complications or are inapplicable for the genital region. Methods. A patient with localized foul odor in the genital hair bearing area was treated with botulinum toxin A. Results. Botulinum toxin A was effective in creating an odorless and anhydrous response in the genital region, and no major adverse effects were noted during a follow-up of 9 months after injection. Conclusion. Local injection of botulinum toxin A appears to be a useful treatment for foul genital odor related to sweat glands activity. [source]


    Maladaptation to mental stress mitigated by the adaptive immune system via depletion of naturally occurring regulatory CD4+CD25+ cells

    DEVELOPMENTAL NEUROBIOLOGY, Issue 6 2006
    Hagit Cohen
    Abstract Peripheral cellular immunity was recently shown to play a critical role in brain plasticity and performance. The antigenic specificity of the participating T cells, however, was not investigated, and nor was their relevance to psychological stress. Here we show, using a mouse model, that adaptive immunity mitigates maladaptation to the acute psychological stress known to trigger abnormal behaviors reminiscent of human post-traumatic stress disorder. Assessment of behavioral adaptation (measured by the acoustic startle response and avoidance behavior) in mice after their exposure to predator odor revealed that maladaptation was several times more prevalent in T cell-deficient mice than in their wild-type counterparts. A single population of T cells reactive to central nervous system (CNS)-associated self-protein was sufficient to endow immune-deficient mice with the ability to withstand the psychological stress. Naturally occurring CD4+CD25+ regulatory T cells were found to suppress this endogenous anti-stress attribute. These findings suggest that T cells specific to abundantly expressed CNS antigens are responsible for brain tissue homeostasis and help the individual to cope with stressful life episodes. They might also point the way to development of immune-based therapies for mental disorders, based either on up-regulation of T cells that partially cross-react with self-antigens or on weakening of the activity of regulatory T cells. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source]


    Olfactory learning in the rat immediately after birth: Unique salience of first odors

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2009
    Stacie S. Miller
    Abstract An infant rat's chance of survival is increased when it remains close to the nest. Early olfactory learning supports such adaptive behavior. Previous experiments indicated that non-associative odor exposure immediately after birth promoted later attachment to a similarly scented artificial nipple. The goal of the current experiments was to extend these findings on olfactory learning in the hours after birth by: exposing pups to more than one odor exposure (Experiment 1), dissecting the role of timing versus order of odor exposure (Experiment 2), testing the odor specificity of these effects (Experiments 3 and 4), and evaluating associative odor conditioning soon after birth (Experiment 5). Without explicit prior odor experience, pups only hours old do not respond much to a novel odor. Prior non-associative odor experience increases later motor activity to that same odor and to novel odors. Furthermore, these findings may be specific to certain amodal dimensions of the (in our case) lemon odor exposure. Single odor non-associative and associative conditioning was equally effective immediately after birth and during the third postnatal hour. Nevertheless, pups given two mere odor exposures responded to the first one more than the second at test, regardless of whether the exposures began immediately or 2,hr after birth. Possible mechanisms for these findings concerning early olfactory learning are discussed. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 488,504, 2009 [source]


    Olfactory association learning and brain-derived neurotrophic factor in an animal model of early deprivation

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2009
    Betty Zimmerberg
    Abstract Animal models can serve to explore neural mechanisms underlying the effects of stressful early experiences on behaviors supporting attachment. Neonatal rats primarily use olfaction for attachment, and Brain-Derived Neurotrophic Factor (BDNF) may be a key transcription target in olfactory association learning. In this experiment, neonatal male and female rats were isolated individually for 3 hr daily in the first week of life while their dams were left with partial litters (Early Deprivation, ED) or remained undisturbed (Control). At 1 week of age, subjects were tested using a 2-day classical conditioning paradigm. The conditioned group (O/M) was exposed to a novel odor paired with a milk infusion. Three additional groups included an unpaired odor and milk exposure group (O/M unP), an odor exposure alone group (O/NM), and neither an odor nor a milk group (NO/NM). Learning the odor association, as revealed in a position preference for the novel odor, was accompanied by an increase in hippocampal BDNF in O/M subjects from undisturbed Control litters. BDNF levels were also positively related to degree of preference for the odor in the O/M Control group. ED subjects did not make the classically conditioned odor association and did not show an increase in hippocampal BDNF. ED increased BDNF levels in the olfactory bulb compared to Controls regardless of training group; individual levels were not correlated with performance because samples were pooled. These results suggest that changes in the transcription of BDNF may underlie some of the long-term consequences of the early stress of maternal separation. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 333,344, 2009. [source]


    Olfactory learning in the rat neonate soon after birth

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2008
    Stacie S. Miller
    Abstract The first hours of a newborn rat's life entail locating and attaching to the mother's nipple not only for nutrition but also for protection and warmth. The present study sought to characterize olfactory learning in the rat neonate immediately after birth. Newborn rats were exposed to an odor at various time periods soon after birth and tested for behavioral activation and attachment to a surrogate nipple in the presence of this odor at 4,5 hr postpartum. Regardless of when pups were presented the odor (0, 1, or 2 hr after birth) motor activity was greater among pups previously exposed to the odor than pups with no odor experience. Similarly, latency to attach to the nipple in the presence of the odor was lower among odor-preexposed pups, especially when odor exposure began within an hour of cesarean delivery. Odor exposure immediately after birth for just 15 min was sufficient to increase motor activity and to decrease latency to attach to a similarly scented surrogate nipple. These results suggest that olfactory experience very soon after birth can shape subsequent olfactory responses. The relative importance of the dearth of postnatal experience or of elevated neurochemicals immediately after birth and possible associative mechanisms underlying this learning is discussed. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 554,565, 2008. [source]


    Rats selectively bred for low levels of 50 kHz ultrasonic vocalizations exhibit alterations in early social motivation

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2008
    K.M. Harmon
    Abstract In rats, the rates of 50 kHz ultrasonic vocalizations (USVs) can be used as a selective breeding phenotype and variations in this phenotype can be an indicator of affective states. The 50 kHz USV is elicited by rewarding stimuli (e.g., food, sexual behavior) and therefore can express a positive affective state. Conversely, the 22 kHz USV is elicited by aversive stimuli (e.g., presence of a predator, social defeat) indicating a negative affective state. In the present study, we tested the effect of selectively breeding for 50 kHz USVs on a variety of maternal social/emotional behaviors in young rat pups (PND 10-12). These measures consisted of an assessment of isolation calls and conditioned odor preference paradigm. Results indicate that animals selected for low levels of 50 kHz USVs show the greatest alterations in social behaviors compared to the control animals. The low line animals had an increase in isolation calls tested during place preference conditioning and a decrease in 50 kHz ultrasonic calls in all conditions. These same low line animals failed to show a typical preference for a maternally-associated odor during the place preference test. The different social behaviors of the high line animals did not consistently vary from those of the control group. These results have important implications for the study of genetic and epigenetic mechanisms underlying emotional states, and possibly contribute to the research underlying the emotional changes in developmental disorders such as autistic spectrum disorder by providing a novel animal model that displays communication deficits that are interdependent with significant social behavioral impairments. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 322,331, 2008. [source]


    Extinction in the developing rat: An examination of renewal effects

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2007
    Carol S.L. Yap
    Abstract In the present series of experiments the context-specificity of extinction was examined from a developmental perspective. For postnatal day (PN) 23 rats, renewal of freezing to an aversive odor conditioned stimulus (CS) was observed when rats were conditioned in Context A, extinguished in Context B, and tested in Context A (i.e., ABA renewal). This effect was not observed in PN16 rats, which is consistent with previous studies suggesting that rats <,PN20 are impaired in encoding contextual information [i.e., Carew and Rudy [1991]. Developmental Psychobiology, 24, 191,209]. Subsequent experiments demonstrated that for rats conditioned at PN16 and tested at PN23, contextual regulation of extinction performance depended on the age at which extinction occurred. Specifically, ABA renewal was observed in rats given extinction training at PN22 but not in rats given extinction training at PN17. These latter results show that whether or not context regulates the expression of an ambiguous memory is determined by the animal's age when the memory becomes ambiguous. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 565-575, 2007. [source]


    Effects of neonatal novelty exposure on sexual behavior, fear, and stress-response in adult rats

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2007
    Fernando Benetti
    Abstract Environmental stimuli in early life may result in permanent behavioral and physiological changes. Present study evaluated the effects of exposing pups to a novel environment on behaviors (open-field test and sexual behavior) and prolactin stress-responses in adult male rats. Half of a litter was daily removed outside (OUT) from the nest and stimulated by handling for 3 min, while the other half remained inside (IN) the nest and was also handled for the same period during the first 10 days postpartum. Maternal behavior after all the pups were returned to the nest was not different between IN and OUT littermates. In adulthood, OUT males showed increased general and central locomotion activity in the open-field test, reduced sexual behavior, and attenuated prolactin secretion in response to restraint stress compared with the IN littermates. The repeated exposition of rat pups to a novel environment is a causal factor for the long-lasting behavioral and endocrine changes. The premature exposition of the pup to unfamiliar environments decreases fear and stress-response, and also reduces sexual behavior. We suggest that the absence of the odor of the mother may be crucial to explain the effects detected in adulthood. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 258,264, 2007. [source]


    The "smellscape" of mother's breast: Effects of odor masking and selective unmasking on neonatal arousal, oral, and visual responses

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2007
    Sébastien Doucet
    Abstract Lactating women emit odor cues that release activity in newborns. Such cues may be carried in various substrates, including milk or areolar secretions. The present study aimed to examine the responses of infants facing their mother's breast and to sort out the source(s) of active volatile compounds emitted by the lactating breast. Infants (aged 3,4 days) were presented their mother's breast in two consecutive trials of 90 s each: a scentless condition (breast entirely covered with a transparent film) paired with one of four odorous conditions (fully exposed breast: n,=,15; nipple only exposed: 15; areola only exposed: 13; and milk exposed: 12). The infants were more orally activated when facing any of the odorous breast conditions than when facing the scentless breast. They cried earlier and longer, and opened their eyes less, when facing the scentless breast. Nipple, Areola, and Milk odors appeared to be equivalent to the whole breast odor in stimulating oral activity and in delaying crying onset. This study shows that volatile compounds originating in areolar secretions or milk release mouthing, stimulate eye opening, and delay and reduce crying in newborns. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 129,138, 2007. [source]


    Amniotic fluid can act as an appetitive unconditioned stimulus in preweanling rats

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2007
    Carlos Arias
    Abstract Studies in humans and animals indicate that exposure to flavors in the amniotic fluid during the later gestational period may induce preferences for those flavors. Considering that during the last prenatal period the amniotic fluid contains substances that activate the opioid system, and that this system plays a critical role in the acquisition of olfactory preferences early in life, it has been hypothesized that the amniotic fluid may acquire appetitive unconditioned properties during this period. This has been tested in an experiment in which preweanling rats were exposed to alcohol odor (CS) paired or unpaired with the intraoral infusion of amniotic fluid (US) collected on gestational day 20. The pairing of these two stimuli induced an enhanced palatability of alcohol's flavor as well an increased intake of the drug. These results support the idea that amniotic fluid acquires appetitive unconditioned properties during the last days of gestation and suggest that associative mechanisms involving the amniotic fluid could be underlying odor and taste preferences acquired through fetal exposure. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 139,149, 2007. [source]


    Development of individually distinct recognition cues

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2006
    Jill M. Mateo
    Abstract Despite extensive research on the functions of kin recognition, little is known about ontogenetic changes in the cues mediating such recognition. In Belding's ground squirrels, Spermophilus beldingi, secretions from oral glands are both individually distinct and kin distinct, and function in social recognition across many contexts. Behavioral studies of recognition and kin preferences suggest that these cues may change across development, particularly around the time of weaning and emergence from natal burrows (around 25 days of age). I used an habituation-discrimination task with captive S. beldingi, presenting subjects with odors collected from a pair of pups at several ages across early development. I found that at 21 days of age, but not at 7 or 14, young produce detectable odors. Odors are not individually distinct, however, until 28 days of age, after young have emerged from their burrows and begun foraging. In addition, an individual's odor continues to develop after emergence: odors produced by an individual at 20 and 40 days of age are perceived as dissimilar, yet odors produced at 28 and 40 days are treated as similar. Developmental changes in odors provide a proximate explanation for why S. beldingi littermate preferences are not consolidated until after natal emergence, and demonstrate that conspecifics must update their recognition templates as young develop. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 508,519, 2006. [source]


    Maternal and littermate deprivation disrupts maternal behavior and social-learning of food preference in adulthood: Tactile stimulation, nest odor, and social rearing prevent these effects

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2006
    Angel I. Melo
    Abstract Maternal and littermate (social) separation, through artificial rearing (AR), disrupts the development of subsequent maternal behavior and social learning in rats. The addition of maternal-licking-like stimulation during AR, partially reverses some of these effects. However, little is know about the role of social stimuli from littermates and nest odors during the preweaning period, in the development of the adult maternal behavior and social learning. The purpose of this study was to examine the effects of peer- and peer-and-odor rearing on the development of maternal behavior and social learning in rats. Female pups were reared with mothers (mother reared,MR) or without mothers (AR) from postnatal day (PND) 3. AR rats received three different treatments: (1) AR-CONTROL group received minimal tactile stimulation, (2) AR-ODOR females received exposure to maternal nest material inside the AR-isolation-cup environment, (3) AR-SOCIAL group was reared in the cup with maternal nest material and a conspecific of the same-age and same-sex and received additional tactile stimulation. MR females were reared by their mothers in the nest and with conspecifics. In adulthood, rats were tested for maternal behavior towards their own pups and in a social learning task. Results confirm our previous report that AR impairs performance of maternal behavior and the development of a social food preference. Furthermore, social cues from a littermate, in combination with tactile stimulation and the nest odor, reversed the negative effects of complete isolation (AR-CONTROL) on some of the above behaviors. Exposure to the odor alone also had effects on some of these olfactory-mediated behaviors. These studies indicate that social stimulation from littermates during the preweaning period, in combination with odor from the nest and tactile stimulation, contributes to the development of affiliative behaviors. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 209,219, 2006. [source]


    Postnatal stress in mice: Does "stressing" the mother have the same effect as "stressing" the pups?

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2004
    A. Moles
    Abstract Short- and long-term effects of brief maternal separation, maternal exposure to novel male odor, and standard rearing were compared in NMRI mice. The first condition consisted of 15 min of daily exposure of pups to clean bedding (CB), and the second condition consisted of 15 min of mothers' exposure to the odor of strange males (SM), for 14 days after birth starting from postnatal Day 1. Thus, both conditions entailed the same period of maternal separation. A control mother,offspring group was left undisturbed (nonhandled, N-H). Corticosterone levels of mothers and pups were measured at the end of the last manipulation session. Corticosterone levels were higher in SM mothers, differing from both those of CB and of control dams; CB pups showed the highest corticosterone levels in comparison with the pups belonging to the other groups. Maternal behavior observed as furthest as possible from the daily separation session did not differ among the three groups. The behavioral response to 0.5 mg/kg of apomorphine in 15-day-old pups was enhanced in both CB and SM animals, which suggests an alteration of dopaminergic functioning. Finally, adult CB and SM male mice showed an increase in the percentage of time and entries into the open arms of the plus-maze in comparison to nonhandled males. This study indicates that exposure to ecologically relevant stimuli elicited a stress response in lactating dams. This "social stress" brings about short- and long-term effects in the offspring, even in the absence of any direct manipulation of the pups. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 230,237, 2004. [source]


    Transnatal olfactory continuity in the rabbit: Behavioral evidence and short-term consequence of its disruption

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2002
    Gérard Coureaud
    Abstract This study investigates the role of prenatal odor learning on postnatal adaptive orientation responses in the newborn rabbit. Preference tests revealed that pups are equally attracted to the odors of placentae and colostrum (Experiments 1,4), suggesting that an odor continuity may exist between the fetal and neonatal environments. To test some predictions derived from this hypothesis, we manipulated the odor of the diet of pregnant-lactating does to control the chemical niches of their perinates. Fetuses exposed in this way to the odor of cumin (C) were selectively attracted as neonates to the odor of pure C (Experiment 6). Prenatal exposure to C also was followed, to a certain extent, by enhanced attraction to C odor in the placenta or colostrum from females which had consumed it (Experiments 5 & 7). Finally, the functional implications of perinatal odor continuity were tested by disrupting it. The odor component of the feto,neonatal transitional environment revealed indeed to affect the ability of certain pups to gain colostrum and milk at the very first sucking opportunities (Experiment 8). © 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 372,390, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/dev.10038 [source]