1
|
Courtiol E, Wilson DA. The Olfactory Mosaic: Bringing an Olfactory Network Together for Odor Perception. Perception 2016; 46:320-332. [PMID: 27687814 DOI: 10.1177/0301006616663216] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Olfactory perception and its underlying neural mechanisms are not fixed, but rather vary over time, dependent on various parameters such as state, task, or learning experience. In olfaction, one of the primary sensory areas beyond the olfactory bulb is the piriform cortex. Due to an increasing number of functions attributed to the piriform cortex, it has been argued to be an associative cortex rather than a simple primary sensory cortex. In fact, the piriform cortex plays a key role in creating olfactory percepts, helping to form configural odor objects from the molecular features extracted in the nose. Moreover, its dynamic interactions with other olfactory and nonolfactory areas are also critical in shaping the olfactory percept and resulting behavioral responses. In this brief review, we will describe the key role of the piriform cortex in the larger olfactory perceptual network, some of the many actors of this network, and the importance of the dynamic interactions among the piriform-trans-thalamic and limbic pathways.
Collapse
Affiliation(s)
- Emmanuelle Courtiol
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Department of Child and Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Donald A Wilson
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Department of Child and Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA
| |
Collapse
|
2
|
Significance of sniffing pattern during the acquisition of an olfactory discrimination task. Behav Brain Res 2016; 312:341-54. [PMID: 27343936 DOI: 10.1016/j.bbr.2016.06.039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 06/16/2016] [Accepted: 06/20/2016] [Indexed: 11/24/2022]
Abstract
Active sampling of olfactory environment consists of sniffing in rodents. The importance of sniffing dynamics is well established at the neuronal and behavioral levels. Patterns of sniffing have been shown to be modulated by the physicochemical properties of odorants, particularly concentration and sorption. Sniffing is also heavily impacted by higher processing related to the behavioral context, emotion and attentional demand. However, how the pattern of sniffing evolves over the course of learning of an experimental olfactory conditioning is still poorly understood. We tested this question by monitoring sniffing activity, using a whole-body plethysmograph, on rats performing a two-alternative choice odor discrimination task. We followed sniff variations at different learning stages (naïve, well-trained, expert). We found that during the acquisition of an odor discrimination task, rats acquired a global sniffing pattern, independent of the odor pair used. This pattern consists of a longer sampling duration, a higher sniffing frequency, and a larger amplitude. In parallel, subtle differences of sniffing between the two odors of a pair were also observed. This sniffing behavior was not only associated with a better and faster acquisition of the discrimination task but was also transferred to other odor sets and refined after a long-term pause so as to reduce the sampling duration and maintain a specific sniffing frequency. Our results provide additional arguments that sniffing is a complex sensorimotor act that is strongly affected by olfactory learning.
Collapse
|
4
|
Schneider P, Müller AT, Gabernet G, Button AL, Posselt G, Wessler S, Hiss JA, Schneider G. Hybrid Network Model for "Deep Learning" of Chemical Data: Application to Antimicrobial Peptides. Mol Inform 2016; 36. [PMID: 28124834 DOI: 10.1002/minf.201600011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 02/24/2016] [Indexed: 01/26/2023]
Abstract
We present a "deep" network architecture for chemical data analysis and classification together with a prospective proof-of-concept application. The model features a self-organizing map (SOM) as the input layer of a feedforward neural network. The SOM converts molecular descriptors to a two-dimensional image for further processing. We implemented lateral neuron inhibition for contrast enhancement. The model achieved improved classification accuracy and predictive robustness compared to feedforward network classifiers lacking the SOM layer. By nonlinear dimensionality reduction the networks extracted meaningful chemical features from the data and outperformed linear principal component analysis (PCA). The learning machine was trained on the sequence-length independent recognition of antibacterial peptides and correctly predicted the killing activity of a synthetic test peptide against Staphylococcus aureus in an in vitro experiment.
Collapse
Affiliation(s)
- Petra Schneider
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland.,inSili.com LLC, Segantinisteig 3, CH-8049, Zurich, Switzerland
| | - Alex T Müller
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| | - Gisela Gabernet
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| | - Alexander L Button
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| | - Gernot Posselt
- Paris-Lodron Universität Salzburg, Division of Microbiology, Billroth Str. 11, A-5020 Salzburg, Austria
| | - Silja Wessler
- Paris-Lodron Universität Salzburg, Division of Microbiology, Billroth Str. 11, A-5020 Salzburg, Austria
| | - Jan A Hiss
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| | - Gisbert Schneider
- Swiss Federal Institute of Technology (ETH), Department of Chemistry and Applied Biosciences, Vladimir-Prelog-Weg 4, CH-8093, Zurich, Switzerland
| |
Collapse
|
5
|
Nativio P, Zoratto F, Romano E, Lacivita E, Leopoldo M, Pascale E, Passarelli F, Laviola G, Adriani W. Stimulation of 5-HT7 receptor during adolescence determines its persistent upregulation in adult rat forebrain areas. Synapse 2015; 69:533-42. [PMID: 26364910 DOI: 10.1002/syn.21846] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/15/2015] [Accepted: 07/30/2015] [Indexed: 12/21/2022]
Abstract
Brain serotonin 7 (5-HT7) receptors play an important functional role in learning and memory, in regulation of mood and motivation, and for circadian rhythms. Recently, we have studied the modulatory effects of a developmental exposure (under subchronic regimen) in rats with LP-211, a brain-penetrant and selective 5-HT7 receptor agonist. We aimed at further deciphering long-term sequelae into adulthood. LP-211 (0.250 mg/kg i.p., once/day) was administered for 5 days during the adolescent phase (postnatal days 43-45 to 47-49). When adult (postnatal days >70), forebrain areas were obtained for ex vivo immunohistochemistry, whose results prompted us to reconsider the brain connectivity maps presented in our previous study (Canese et al., Psycho-Pharmacol 2015;232:75-89.) Significant elevation in levels of 5-HT7 receptors were evidenced due to adolescent LP-211 exposure, in dorsal striatum (which also shows an increase of dopaminergic D2 auto-receptors) and-unexpectedly-in piriform cortex, with no changes in ventral striatum. We observed that functional connectivity from a seed on the right hippocampus was more extended than reported, also including the piriform cortex. As a whole, the cortical loop rearranged by adolescent LP-211 exposure consisted in a hippocampus receiving connections from piriform cortex and dorsal striatum, the latter both directly and through functional control over the 'extended amygdala'. Such results represent a starting point to explore neurophysiology of 5-HT7 receptors. Further investigation is warranted to develop therapies for sleep disorders, for impaired emotional and motivational regulation, for attentive and executive deficit. The 5-HT7 agonist LP-211 (0.250 mg/kg i.p., once/day) was administered for 5 days during adolescence (postnatal days 43-45 to 47-49) in rats. When adult (postnatal days >70), a significant elevation in levels of 5-HT7 receptors were evidenced in dorsal striatum and-unexpectedly-in piriform cortex.
Collapse
Affiliation(s)
- Paola Nativio
- Departments of Molecular Medicine and of Medical Surgical Sciences and Biotechnology, "Sapienza" University of Rome, Rome, Italy
| | - Francesca Zoratto
- Department of Cell Biology and Neurosciences, Istituto Superiore Di Sanità, Rome, Italy
| | - Emilia Romano
- Department of Cell Biology and Neurosciences, Istituto Superiore Di Sanità, Rome, Italy
| | - Enza Lacivita
- Department of Pharmacy, Università Degli Studi "a. Moro", Bari, Italy
| | - Marcello Leopoldo
- Department of Pharmacy, Università Degli Studi "a. Moro", Bari, Italy
| | - Esterina Pascale
- Departments of Molecular Medicine and of Medical Surgical Sciences and Biotechnology, "Sapienza" University of Rome, Rome, Italy
| | - Francesca Passarelli
- Departments of Molecular Medicine and of Medical Surgical Sciences and Biotechnology, "Sapienza" University of Rome, Rome, Italy
| | - Giovanni Laviola
- Department of Cell Biology and Neurosciences, Istituto Superiore Di Sanità, Rome, Italy
| | - Walter Adriani
- Department of Cell Biology and Neurosciences, Istituto Superiore Di Sanità, Rome, Italy
| |
Collapse
|
6
|
Martel G, Simon A, Nocera S, Kalainathan S, Pidoux L, Blum D, Leclère-Turbant S, Diaz J, Geny D, Moyse E, Videau C, Buée L, Epelbaum J, Viollet C. Aging, but not tau pathology, impacts olfactory performances and somatostatin systems in THY-Tau22 mice. Neurobiol Aging 2014; 36:1013-28. [PMID: 25433460 DOI: 10.1016/j.neurobiolaging.2014.10.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 10/01/2014] [Accepted: 10/24/2014] [Indexed: 11/15/2022]
Abstract
Somatostatin (SOM) cortical levels decline in Alzheimer's disease (AD) in correlation with cognitive impairment severity, the latter being closely related to the presence of neurofibrillary tangles. Impaired olfaction is another hallmark of AD tightly related to tau pathology in the olfactory pathways. Recent studies showed that SOM modulates olfactory processing, suggesting that alterations in SOM levels participate to olfactory deficits in AD. Herein, we first observed that human olfactory peduncle and cortex are enriched in SOM cells and fibers, in aged postmortem brains. Then, the possible link between SOM alterations and olfactory deficits was evaluated by exploring the impact of age and tau hyperphosphorylation on olfactory SOM networks and behavioral performances in THY-Tau22 mice, a tauopathy transgenic model. Distinct molecular repertoires of SOM peptide and receptors were associated to sensory or cortical olfactory processing structures. Aging mainly affected SOM neurotransmission in piriform and entorhinal cortex in wild-type mice, although olfactory performances decreased. However, no further olfactory impairment was evidenced in THY-Tau22 mice until 12 months although tau pathology early affected olfactory cortical structures. Thus, tau hyperphosphorylation per se has a limited impact on olfactory performances in THY-Tau22 mice.
Collapse
Affiliation(s)
- Guillaume Martel
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Axelle Simon
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Sonia Nocera
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Sahana Kalainathan
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Ludivine Pidoux
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - David Blum
- Inserm, UMR837, Jean-Pierre Aubert Research Centre, IMPRT, F-59000, Lille, France; Université de Lille, UDSL, F-59000, Lille, France
| | | | - Jorge Diaz
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - David Geny
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Emmanuel Moyse
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Catherine Videau
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Luc Buée
- Inserm, UMR837, Jean-Pierre Aubert Research Centre, IMPRT, F-59000, Lille, France; Université de Lille, UDSL, F-59000, Lille, France
| | - Jacques Epelbaum
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Cécile Viollet
- Inserm, UMR894, Center for Psychiatry & Neuroscience, 75014, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France.
| |
Collapse
|