INTRODUCTION In vivo, most neurons in the main olfactory bulb exhibit robust spontaneous activity. This paper tests the hypothesis that spontaneous activity in olfactory receptor neurons drives much of the spontaneous activity in mitral and tufted cells via excitatory synapses. METHODS Single units were recorded in vivo from the main olfactory bulb of a rat before, during, and after applicati...

OBJECTIVES/HYPOTHESIS There is evidence that the olfactory system can be modulated by repeated exposure to odors, a procedure called olfactory training. The aim of this study was to assess the effectiveness of olfactory training in patients with postinfectious and post-traumatic olfactory dysfunction. STUDY DESIGN Prospective study of 119 patients with postinfectious and post-traumatic olfact...

The olfactory cyclic nucleotide-gated channel subunit 1 (OCNC1) is required for signal transduction in olfactory receptor cells. To further investigate the role of this channel in the olfactory system, the biochemical and morphological consequences of targeted disruption of OCNC1 were investigated in adult mice. Null as compared to wild-type mice had smaller olfactory bulbs, suggesting compromi...

Compared with visual and auditory imagery, little is known about olfactory imagery. There is evidence that respiration may be altered by both olfactory perception and olfactory imagery. In order to investigate this relationship, breathing parameters (respiratory minute volume, respiratory amplitude, and breathing rate) in human subjects during olfactory perception and olfactory imagery were inv...

Sensory input is essential for the normal development of sensory centers in the brain, such as the somatosensory, visual, auditory, and olfactory systems. Visual deprivation during a specific developmental stage, called the critical period, results in severe and irreversible functional impairments in the primary visual cortex. Olfactory deprivation in the early postnatal period also causes sign...

OBJECTIVES To determine whether transnasal excision of olfactory epithelium is a safe, effective therapy and to learn more of the pathogenesis of phantosmia by studying the histological features of the excised mucosa. DESIGN A retrospective study consisting of a medical record review and telephone survey. Follow-up ranged from 1 to 11 years (average, 5.4 years). Excised tissues were histologi...

Life-long neurogenesis is a characteristic feature of the olfactory pathways of a phylogenetically diverse array of animals. In both vertebrates and invertebrates, the life-long addition of olfactory interneurons in the brain occurs in parallel with the continuous proliferation of olfactory receptor neurons in the olfactory organ. It has been proposed that these two processes are related functi...

Chronic rhinosinusitis is the most frequent cause of hyposmia. We established a new experimental animal model to investigate pathological findings in the olfactory epithelium and olfactory bulb of rats and describe the possible etiology of hyposmia due to rhinosinusitis. Not only dysfunction of the olfactory epithelium but a central type of hyposmia caused by disorders of the olfactory bulb was...

Although the function of the adult olfactory system has been thoroughly studied, the molecular mechanisms regulating the initial formation of the olfactory nerve, the first cranial nerve, remain poorly defined. Here, we provide evidence that both modulated Notch and bone morphogenetic protein (BMP) signaling affect the generation of neurons in the olfactory epithelium and reduce the number of m...

Although considerable effort has been directed toward developing an understanding of vertebrate olfaction (see Sections 6.1–6.10), the complexity of the vertebrate olfactory system presents many challenges. This complexity is in part due to the large number of processing channels in this system: the mouse genome encodes more than a thousand odorant receptors, and the mouse olfactory bulb has mo...