China
Africa
Explore chapters and articles related to this topic
Olfaction in Palliative Care Patients
Published in Victor R. Preedy, Handbook of Nutrition and Diet in Palliative Care, 2019
Sagit Shushan, Arkadi Yakirevitch
Following transduction in the OE, neural signals progress along the bi-polar neurons, through the cribriform plate, to synapse with dendrites of mitral and tufted cells within the olfactory bulb. Axonal projections from those cells convey into the lateral olfactory tract, to terminate at primary olfactory cortex. Primary cortex is defined as the regions that receive direct projections from the olfactory bulb and includes the anterior olfactory nucleus, ventral tenia tecta, anterior hippocampus, olfactory tubercle, piriform cortex, amygdala, periamygdaloid cortex and entorhinal cortex. The secondary olfactory cortex is defined as regions that receive projections from primary olfactory cortex, either through direct projection or indirect via the thalamic nucleus. This higher-order cortex includes the orbito-frontal cortex, anterior insula, hypothalamus, mediodorsal thalamus and hippocampus. Finally, many of the regions of primary olfactory cortex send dense feedback projections to the olfactory bulb (Uchida et al. 2014). All of these act together to create the perception of smell. The anatomical projection to the hypothalamus emphasizes the importance of olfaction in eating and nutrition.
Investigational drugs for the treatment of olfactory dysfunction
Published in Expert Opinion on Investigational Drugs, 2022
Arianna Di Stadio, Cinzia Severini, Andrea Colizza, Marco De Vincentiis, Ignazio La Mantia
The neuroepithelium is connected through the axons of the ORN to the olfactory bulb, which contains glomerulus, mitral cells and tufted relay neurons. The axons converge in the glomerulus to form the first cranial nerve (olfactory nerve). The glomerulus is connected by synapses to the mitral cells; the latter together with the tufted relay neurons forms the olfactory tract. This structure bifurcates in the medial and lateral olfactory stria (y inverted-shaped). The olfactory stimulus is conducted through these structures up to the piriform cortex, the periamygdaloid cortex, the olfactory tuberculosis and the anterior olfactory nucleus. The primary olfactory cortex is formed by the medial and lateral olfactory stria and the anterior perforated substance. The lateral olfactory stria is extended posteriorly giving origin to the entorhinal area which, together with the uncus, forms the secondary olfactory cortex, also known as the orbitofrontal cortex (Figure 2). This area is straightly related to memory. The primary cortex is responsible for the active perception of the sense of smell, while the secondary one is the portion where the smell perception is integrated with emotions and memory.