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Leonardo B. M. Resstel - One of the best experts on this subject based on the ideXlab platform.
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Anxiety-Behavior Modulated by Ventral Medial Prefrontal Cortex of Rats Submitted to the Vogel Conflict Test Involves a Local NMDA Receptor and Nitric Oxide
Journal of Behavioral and Brain Science, 2011Co-Authors: Sabrina F. Lisboa, Francisco Silveira Guimarães, Leonardo B. M. ResstelAbstract:It was demonstrated in the Vogel conflict test (VCT) that the ventral portion of medial prefrontal cortex (vMPFC) of rats is involved with anxiety behavior. Moreover, the vMPFC local glutamatergic and nitrergic system interaction is involved in modulation of fear conditioning, a model of anxiety. To better understand the role of the MPFC-glutamatergic and nitrergic system on the VTC behavior response, male Wistar rats (250 g) were water deprived for 48 h before the VCT. After 24 h of water deprivation, they were subjected to an initial 3-min non-punished (pre-test) drinking session. Twenty-four hours later bilateral microinjections of NMDA-antagonist LY235959 (4 nmol/200 nL), the specific nNOS inhibitor N-Propyl-L-arginine (N-Propyl –0.08 nmol/200 nL), the NO scavenger Carboxi-PTIO (C-PTIO, 2 nmol/200 nL) or 200nL of vehicle were applied in the vMPFC. After 10 min, the animals were submitted to 3-min punished-licking session. LY235959 increased the number of punished licks. Similar to LY235959, both N-Propyl and C-PTIO also increased the number of punished licks. No changes were observed when LY235959, N-Propyl and C-PTIO were micro- injected into vMPFC surrounding structures such as the cingulate cortex area 1, the corpus callosum and the Tenia Tecta. In control experiments these drugs did not change neither the number of unpunished licks nor had any effect in the tail-flick test. The results show that NO signaling in the vMPFC can modulate anxiety-behavior in the VCT by control punished behavior. Moreover, this NO modulation could be associated with local glutamatergic activation through NMDA receptors
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Opposite role of infralimbic and prelimbic cortex in the tachycardiac response evoked by acute restraint stress in rats.
Journal of neuroscience research, 2009Co-Authors: Rodrigo Fiacadori Tavares, Fernando M.a. Correa, Leonardo B. M. ResstelAbstract:The ventral medial prefrontal cortex (vMPFC) comprises the prelimbic cortex (PL) and the infralimbic cortex (IL). Conflicting results have been reported from studies aiming to investigate the role played by the vMPFC in behavioral and autonomic responses evoked in rodents exposed to experimental protocols that promote defense responses. Acute restraint is an unavoidable stress situation that evokes marked and sustained cardiovascular changes, which are characterized by elevated blood pressure (BP) and intense heart rate (HR) increases. We report here a comparison between the effects of pharmacological inhibition of IL and PL neurotransmission on BP and HR responses evoked by acute restraint in rats. Bilateral microinjection of 200 nl of the unspecific synaptic blocker CoCl2 (1 mM) into the PL increased HR response associated with restraint, without affecting the restraint-induced BP response. However, when local synapses in the IL were inhibited by bilateral injection of CoCl2 into that area, the restraint-induced HR increases were significantly reduced, without a significant effect on the concomitant BP response. No responses were observed when CoCl2 was microinjected into structures surrounding the vMPFC, such as the cingulate cortex area 1, the corpus callosum, or the Tenia Tecta. The present results confirm the involvement of the vMPFC in modulation of the tachycardiac response evoked by acute restraint but not of the restraint-evoked blood pressure response. They also indicate that the IL and PL areas have opposite roles in the cardiac response, facilitating and reducing, respectively, restraint-evoked tachycardiac responses. © 2009 Wiley-Liss, Inc.
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Anxiolytic-like effects induced by medial prefrontal cortex inhibition in rats submitted to the Vogel conflict test
Physiology & Behavior, 2007Co-Authors: Leonardo B. M. Resstel, R.f. Souza, Francisco Silveira GuimarãesAbstract:Abstract Conflicting results have been obtained in studies aimed at investigating the role of the ventral portion of the medial prefrontal cortex (vMPFC), which comprise the prelimbic cortex (PL) and infralimbic cortex (IL), on anxiety responses in rodents evoked by animal models such as fear conditioning, elevated plus maze or social interaction. This may reflect the use of different lesion techniques and/or experimental paradigms based on distinct behaviors properties. Among the latter, the Vogel punished-licking test has been widely used to measure anxiety. However, the role of the vMPFC on anxiety-like behavior evoked by the Vogel model has not been evaluated. Thus, the present study verified the effects of acute and reversible bilateral inhibition of the vMPFC on the behavioral responses in the Vogel conflict test. After 24 h of water deprivation, male Wistar rats were subjected to an initial 3-min non-punished (pretest) drinking session. After an additional 24-h period of water deprivation they were exposed to a 3-min punished-licking session (test).Bilateral microinjections of lidocaine 2% (200 nL) or CoCl 2 (1 mM/200 nL) into the PL or IL produced similar anticonflict effects, increasing the number of punished licks. No responses were observed when lidocaine 2% was microinjected into vMPFC surrounding structures such as the cingulate cortex area 1, the corpus callosum and the Tenia Tecta. In control experiments the drugs did not change the number of unpunished licks nor had any effect in the tail-flick test. The present results, therefore, indicate that the vMPFC is involved in the behavioral responses elicited by punished stimuli.
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Pressor and tachycardic responses evoked by microinjections of L-glutamate into the medial prefrontal cortex of unanaesthetized rats.
The European journal of neuroscience, 2005Co-Authors: Leonardo B. M. Resstel, Fernando M.a. CorreaAbstract:The ventral medial prefrontal cortex (vMPFC) is involved in central cardiovascular control. In the present study, we studied the cardiovascular effects of injections of L-glutamate into the vMPFC of unanaesthetized rats and the mechanisms of these effects. Male Wistar rats were used and L-glutamate was microinjected in the vMPFC in a final volume of 200 nL. Microinjections of L-glutamate (9, 27, 81, 150 or 300 nmol) caused long-lasting, dose-related pressor and tachycardic responses in unanaesthetized rats. No differences were observed among cardiovascular responses when L-glutamate was injected into the three sub-areas that comprise the vMPFC, namely the prelimbic, the infralimbic and the dorsal peduncular cortices. No responses were observed when the dose of 81 nmol of L-glutamate was microinjected into surrounding structures such as the cingulate cortex area 1, the corpus callosum and the Tenia Tecta, indicating a predominant action on the vMPFC. The cardiovascular response to L-glutamate into the vMPFC was blocked by intravenous pretreatment with the ganglion blocker pentolinium (10 mg/kg, i.v.) or the beta 1 -adrenoceptor antagonist atenolol (1.5 mg/kg, i.v.), supporting the involvement of the cardiac sympathetic nervous system in the response to L-glutamate. Pretreatment with the muscarinic antagonist homatropine methyl bromide (1 mg/kg, i.v.) reduced the latency to the onset of the pressor and tachycardic responses to L-glutamate injected into the vMPFC without significant effects on response duration or maximum effect. We conclude that stimulation of the vMPFC with L-glutamate caused pressor and tachycardic responses in unanaesthetized rats, responses which were dependent on cardiac sympathetic nerve activation and were potentiated by blockade of peripheral muscarinic receptors.
Cheryl L. Sisk - One of the best experts on this subject based on the ideXlab platform.
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Increased expression of forebrain GnRH mRNA and changes in testosterone negative feedback following pubertal maturation.
Molecular and cellular endocrinology, 2004Co-Authors: Heather N. Richardson, Andrea C Gore, Jane Venier, Russell D Romeo, Cheryl L. SiskAbstract:Pubertal development is associated with increased activity of the gonadotropin releasing hormone (GnRH) neuronal system and rising gonadal steroid levels. The purpose of this study was to determine whether different circulating levels of testosterone affect GnRH mRNA and luteinizing hormone (LH) to the same degree prior to and following pubertal maturation. Pre- and post-pubertal male Syrian hamsters were gonadectomized and treated with timed-release testosterone pellets (0, 0.5, 1.5, or 2.5mg) for one week. Following treatment, three separate brain tissue dissections containing the majority of GnRH cell bodies, Tenia Tecta and medial septum (TT/MS), diagonal band of Broca/organum vasculosum of the lamina terminalis (DBB/OVLT), and preoptic area (POA), were analyzed for GnRH mRNA levels by RNase protection assay and terminal plasma luteinizing hormone concentrations were determined by radioimmunoassay. Pre-pubertal animals were more sensitive to testosterone negative feedback on LH. Conversely, the ability of testosterone to reduce GnRH mRNA was much greater after pubertal development. Specifically, GnRH mRNA in the TT/MS was considerably higher in adults, and testosterone reduced GnRH mRNA in a dose-dependent manner only in adults. These data indicate that although testosterone is a powerful suppressor of LH release before puberty, it does not have appreciable control over GnRH mRNA until after puberty. Furthermore, the pubertal increase in GnRH mRNA appears to occur via steroid feedback-independent mechanisms in the male Syrian hamster.
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Redefining gonadotropin-releasing hormone (GnRH) cell groups in the male Syrian hamster: testosterone regulates GnRH mRNA in the Tenia Tecta.
Journal of neuroendocrinology, 2002Co-Authors: Heather N. Richardson, David B. Parfitt, Robert C. Thompson, Cheryl L. SiskAbstract:Gonadotropin-releasing hormone (GnRH) regulates the production of testosterone via the hypothalamic-pituitary-gonadal axis and testosterone, in turn, regulates the GnRH system via negative feedback. We compared testosterone regulation of GnRH mRNA expression in four anatomically defined GnRH cell groups in juvenile and adult male Syrian hamsters, including a rostral population of GnRH cells in the Tenia Tecta. In situ hybridization histochemistry (ISHH) was used to measure GnRH mRNA in brains from castrated juveniles and adults treated with 0 mg or 2.5 mg testosterone pellets for one week. ISHH was performed on coronal sections using a 35 S-cRNA probe generated from Syrian hamster GnRH cDNA. Testosterone treatment resulted in a significant reduction in mean area of GnRH neurones covered by silver grains within the Tenia Tecta, but only a trend toward decreased GnRH mRNA in the diagonal band of Broca/organum vasculosum of the lamina terminalis (DBB/OVLT), medial septum (MS), and caudal preoptic area (cPOA). The effects of testosterone were independent of age. Frequency distribution analyses unveiled a significant reduction in the number of heavily labelled cells following testosterone treatment within the Tenia Tecta and MS. Simple regression analyses revealed a significant positive correlation between plasma luteinizing hormone concentrations and GnRH mRNA only in the Tenia Tecta. These data indicate that, overall, GnRH mRNA is modestly reduced by testosterone, and the most robust attenuation of GnRH mRNA occurs within the Tenia Tecta. This is the first report to link mechanisms of steroid negative feedback with Tenia Tecta GnRH neurones, providing a new focus for investigating brain region-specific steroidal regulation of GnRH synthesis.
Masaya Tohyama - One of the best experts on this subject based on the ideXlab platform.
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Localization of oxytocin receptor messenger ribonucleic acid in the rat brain
Endocrinology, 1993Co-Authors: Ryoichi Yoshimura, Hiroshi Kiyama, Tadashi Kimura, Toshiyuki Araki, Hiroshi Maeno, Osamu Tanizawa, Masaya TohyamaAbstract:The expression of oxytocin receptor (OT-R) mRNA in the rat central nervous system was examined by in situ hybridization histochemistry using cRNA probe. Wide distribution of cells expressing OT-R mRNA was observed not only in the hypothalamus, but also in other regions. There were high levels of OT-R mRNA in the anterior olfactory nuclei, Tenia Tecta, olfactory tubercle, rostral most region of the frontal cortex, piriform cortex, layers 2 and 3 of the neocortex, bed nucleus of the stria terminalis, anterior medial preoptic nucleus (AV3V region), magnocellular preoptic nucleus, supraoptic nucleus, paraventricular hypothalamic nucleus, retrochiasmatic nucleus, ventromedial hypothalamic nucleus, paraventricular thalamic nucleus, central amygdaloid nucleus, medial amygdaloid nucleus, posterior cortical amygdaloid nucleus, amygdalohippocampal area, subiculum, prepositus hypoglossal nucleus, and dorsal motor nucleus of vagus. In most regions of the brain, our findings concurred with those obtained by receptor b...
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Region-specific expression of GABAA receptor α3 and α4 subunits mRNAs in the rat brain
Brain research. Molecular brain research, 1992Co-Authors: Toshiyuki Araki, Masaya TohyamaAbstract:Abstract The expression of mRNAs encoding the α3 and α4 subunit of the γ-aminobutyric acid A (GABAA) receptor in the rat brain was investigated by in situ hybridization histochemistry. Both subunits showed a wide but uneven distribution, which did not coincide with the distribution of any other subunit so far reported. The cerebral cortex, anterior olfactory nucleus, lateral septum, subiculum, lateral and medial nuclei of the amygdaloid complex, anterior nuclei of the thalamus, pars compacta of the substantia nigra, trigeminal sensory nuclei, and cochlear nucleus were some of the areas where strong expression of mRNA for both the α3 and α4 subunits was detected. In the granular cell layer of the olfactory bulb, caudate-putamen, Tenia Tecta, pyramidal cell layer of the CA region and granular cell layer of the dentate gyrus in the hippocampal formation, dorsomedial and ventrolateral nuclei of the thalamus, dorsal part of the lateral geniculate body, preolivary nuclei and pontine nuclei, only the α4 subunit showed strong expression. The diverse distribution of these two subunits is considered to indicate that each has a different role in the central nervous system.
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Different postnatal development of cells expressing mRNA encoding neurotensin receptor.
Neuroscience, 1992Co-Authors: Makoto Sato, Hiroshi Kiyama, Masaya TohyamaAbstract:In situ hybridization histochemistry revealed three different ontogenetic patterns of localized expression of the high-affinity type of neurotensin receptor mRNA in the developing rat brain: one comprises sites which showed transient expression of neurotensin receptor mRNA during the first postnatal week, the expression greatly decreasing thereafter (type I); another comprises sites at which there is a gradual increase in neurotensin receptor mRNA after birth, as there is in cell number and intensity, with advancing age, followed by a plateau (type II); the third comprises sites at which there is much expression of neurotensin receptor mRNA already at birth, and a slight decrease thereafter (type III). The cerebral cortex, except retrosplenial and entorhinal cortices, and the anterior dorsal thalamic nucleus exhibit the type I pattern, while the horizontal and vertical limbs of the diagonal band of Broca, magnocellular preoptic nucleus, substantia innominata, ventral part of the suprachiasmatic nucleus, medial habenular nucleus, ventral tegmental area and substantia nigra pars compacta exhibit the type II pattern. The Tenia Tecta, retrosplenial and entorhinal cortices exhibit the type III pattern. One of the most striking findings in this study was that the entire neocortex and most of the limbic cortex exhibit the type I pattern, i.e. neurotensin receptor mRNA is expressed transiently long before a neuronal network is established there. This suggests that neurotensin plays an important role in cortical development, other than its reported transmitter-like role in the adult.
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Distribution of GABAA-receptor α1 subunit gene expression in the rat forebrain
Molecular Brain Research, 1991Co-Authors: Jian-hua Zhang, Toshiyuki Araki, Makoto Sato, Masaya TohyamaAbstract:The localization of neurons containing mRNA of the α1 subunit of the γ-aminobutyric acid-A (GABAA) receptor was examined in the rat forebrain by in situ hybridization histochemistry using an oligonucleotide probe for the α1 subunit. Moderately to strongly labeled neurons were numerous in the mitral cell layer of the olfactory bulb, the anterior olfactory nucleus, the diagonal band of Broca, the globus pallidus, the Tenia Tecta, the hippocampal formation, the thalamic and subthalamic nuclei, the zona incerta, and the amygdaloid complex. A few positive neurons were found in the caudate-putamen, the lateral and medial septal areas, the nucleus accumbens, the bed nucleus of the stria terminalis, the ventral pallidum, and the hypothalamus. The distribution of neurons containing α1 subunit mRNA in the forebrain was very similar to that of neurons expressing β2 subunit mRNA, suggesting that these two subunits frequently coexist in the same neurons in the forebrain.
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Distribution of GABAA-receptor alpha 1 subunit gene expression in the rat forebrain.
Brain research. Molecular brain research, 1991Co-Authors: Jian-hua Zhang, Toshiyuki Araki, Makoto Sato, Masaya TohyamaAbstract:The localization of neurons containing mRNA of the alpha 1 subunit of the gamma-aminobutyric acid-A (GABAA) receptor was examined in the rat forebrain by in situ hybridization histochemistry using an oligonucleotide probe for the alpha 1 subunit. Moderately to strongly labeled neurons were numerous in the mitral cell layer of the olfactory bulb, the anterior olfactory nucleus, the diagonal band of Broca, the globus pallidus, the Tenia Tecta, the hippocampal formation, the thalamic and subthalamic nuclei, the zona incerta, and the amygdaloid complex. A few positive neurons were found in the caudate-putamen, the lateral and medial septal areas, the nucleus accumbens, the bed nucleus of the stria terminalis, the ventral pallidum, and the hypothalamus. The distribution of neurons containing alpha 1 subunit mRNA in the forebrain was very similar to that of neurons expressing beta 2 subunit mRNA, suggesting that these two subunits frequently coexist in the same neurons in the forebrain.
Heather N. Richardson - One of the best experts on this subject based on the ideXlab platform.
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Increased expression of forebrain GnRH mRNA and changes in testosterone negative feedback following pubertal maturation.
Molecular and cellular endocrinology, 2004Co-Authors: Heather N. Richardson, Andrea C Gore, Jane Venier, Russell D Romeo, Cheryl L. SiskAbstract:Pubertal development is associated with increased activity of the gonadotropin releasing hormone (GnRH) neuronal system and rising gonadal steroid levels. The purpose of this study was to determine whether different circulating levels of testosterone affect GnRH mRNA and luteinizing hormone (LH) to the same degree prior to and following pubertal maturation. Pre- and post-pubertal male Syrian hamsters were gonadectomized and treated with timed-release testosterone pellets (0, 0.5, 1.5, or 2.5mg) for one week. Following treatment, three separate brain tissue dissections containing the majority of GnRH cell bodies, Tenia Tecta and medial septum (TT/MS), diagonal band of Broca/organum vasculosum of the lamina terminalis (DBB/OVLT), and preoptic area (POA), were analyzed for GnRH mRNA levels by RNase protection assay and terminal plasma luteinizing hormone concentrations were determined by radioimmunoassay. Pre-pubertal animals were more sensitive to testosterone negative feedback on LH. Conversely, the ability of testosterone to reduce GnRH mRNA was much greater after pubertal development. Specifically, GnRH mRNA in the TT/MS was considerably higher in adults, and testosterone reduced GnRH mRNA in a dose-dependent manner only in adults. These data indicate that although testosterone is a powerful suppressor of LH release before puberty, it does not have appreciable control over GnRH mRNA until after puberty. Furthermore, the pubertal increase in GnRH mRNA appears to occur via steroid feedback-independent mechanisms in the male Syrian hamster.
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Redefining gonadotropin-releasing hormone (GnRH) cell groups in the male Syrian hamster: testosterone regulates GnRH mRNA in the Tenia Tecta.
Journal of neuroendocrinology, 2002Co-Authors: Heather N. Richardson, David B. Parfitt, Robert C. Thompson, Cheryl L. SiskAbstract:Gonadotropin-releasing hormone (GnRH) regulates the production of testosterone via the hypothalamic-pituitary-gonadal axis and testosterone, in turn, regulates the GnRH system via negative feedback. We compared testosterone regulation of GnRH mRNA expression in four anatomically defined GnRH cell groups in juvenile and adult male Syrian hamsters, including a rostral population of GnRH cells in the Tenia Tecta. In situ hybridization histochemistry (ISHH) was used to measure GnRH mRNA in brains from castrated juveniles and adults treated with 0 mg or 2.5 mg testosterone pellets for one week. ISHH was performed on coronal sections using a 35 S-cRNA probe generated from Syrian hamster GnRH cDNA. Testosterone treatment resulted in a significant reduction in mean area of GnRH neurones covered by silver grains within the Tenia Tecta, but only a trend toward decreased GnRH mRNA in the diagonal band of Broca/organum vasculosum of the lamina terminalis (DBB/OVLT), medial septum (MS), and caudal preoptic area (cPOA). The effects of testosterone were independent of age. Frequency distribution analyses unveiled a significant reduction in the number of heavily labelled cells following testosterone treatment within the Tenia Tecta and MS. Simple regression analyses revealed a significant positive correlation between plasma luteinizing hormone concentrations and GnRH mRNA only in the Tenia Tecta. These data indicate that, overall, GnRH mRNA is modestly reduced by testosterone, and the most robust attenuation of GnRH mRNA occurs within the Tenia Tecta. This is the first report to link mechanisms of steroid negative feedback with Tenia Tecta GnRH neurones, providing a new focus for investigating brain region-specific steroidal regulation of GnRH synthesis.
Hiroyuki Manabe - One of the best experts on this subject based on the ideXlab platform.
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Tuning of olfactory cortex ventral Tenia Tecta neurons to distinct task elements of goal-directed behavior.
eLife, 2020Co-Authors: Kazuki Shiotani, Yuta Tanisumi, Koshi Murata, Junya Hirokawa, Yoshio Sakurai, Hiroyuki ManabeAbstract:The ventral Tenia Tecta (vTT) is a component of the olfactory cortex and receives both bottom-up odor signals and top-down signals. However, the roles of the vTT in odor-coding and integration of inputs are poorly understood. Here, we investigated the involvement of the vTT in these processes by recording the activity from individual vTT neurons during the performance of learned odor-guided reward-directed tasks in mice. We report that individual vTT cells are highly tuned to a specific behavioral epoch of learned tasks, whereby the duration of increased firing correlated with the temporal length of the behavioral epoch. The peak time for increased firing among recorded vTT cells encompassed almost the entire temporal window of the tasks. Collectively, our results indicate that vTT cells are selectively activated during a specific behavioral context and that the function of the vTT changes dynamically in a context-dependent manner during goal-directed behaviors.
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Tuning of ventral Tenia Tecta neurons of the olfactory cortex to distinct scenes of feeding behavior
2018Co-Authors: Kazuki Shiotani, Yuta Tanisumi, Koshi Murata, Junya Hirokawa, Yoshio Sakurai, Hiroyuki Manabe, Kensaku MoriAbstract:Ventral Tenia Tecta (vTT) is a part of the olfactory cortex that receives both olfactory sensory signals from the olfactory bulb and top-down signals from the prefrontal cortex. To address the question whether and how the neuronal activity of the vTT is modulated by prefrontal cognitive processes such as attention, expectation and working memory that occurs during goal-directed behaviors, we recorded individual neuronal responses in the vTT of freely moving awake mice that performed learned odor-guided feeding and drinking behaviors. We found that the firing pattern of individual vTT cells had repeatable behavioral correlates such that the environmental and behavioral scene the mouse encountered during the learned behavior was the major determinant of when individual vTT neurons fired maximally. Furthermore, spiking activity of these scene cells was modulated not only by the present scene but also by the future scene that the mouse predicted. We show that vTT receives afferent input from the olfactory bulb and top-down inputs from the medial prefrontal cortex and piriform cortex. These results indicate that different groups of vTT cells are activated at different scenes and suggest that processing of olfactory sensory information is handled by different scene cells during distinct scenes of learned feeding and drinking behaviors. In other words, during the feeding and drinking behavior, vTT changes its working mode moment by moment in accord with the scene change by selectively biasing specific scene cells. The scene effect on olfactory sensory processing in the vTT has implications for the neuronal circuit mechanisms of top-down attention and scene-dependent encoding and recall of olfactory memory.
