olfactory tract

(noun)

A narrow white band made of a bundle of axons connecting the olfactory bulb to several brain regions.

Related Terms

Examples of olfactory tract in the following topics:

  • Olfactory (I) Nerve

    • The olfactory nerve, or cranial nerve I, is the first of the 12 cranial nerves.
    • The specialized olfactory receptor neurons of the olfactory nerve are located in the olfactory mucosa of the upper parts of the nasal cavity.
    • The olfactory nerves consist of a collection of many sensory nerve fibers that extend from the olfactory epithelium to the olfactory bulb, passing through the many openings of the cribriform plate of the ethmoid bone.
    • Olfactory receptor neurons continue to emerge throughout life and extend new axons to the olfactory bulb.
    • These interactions are transduced into electrical activity in the olfactory bulb, which then transmits the electrical activity to other parts of the olfactory system and the rest of the central nervous system via the olfactory tract.

  • Tissues and Aging

    • The sense of smell begins to degenerate with the loss of olfactory sensory neurons and loss of cells from the olfactory bulb.
    • This causes more urinary tract infections in the elderly.
    • The prostate gland is often implicated in various disorders of the urinary tract.
    • With the advancing of age, the airways and tissue of the respiratory tract become less elastic and more rigid.
    • Describe the effects of aging on bones, muscles, the nervous and digestive systems, and the respiratory tract

  • Taste and Smell at Birth and in Old Age

    • Infants are responsive to the olfactory cues associated with maternal breast odors.
    • Studies demonstrate that the changes to the olfactory bulb and main olfactory system following birth are extremely important and influential for maternal behavior.
    • A diagram of the olfactory system is shown in .
    • Pregnancy and childbirth result in a high state of plasticity of the olfactory system that may facilitate olfactory learning within the mother.
    • Human olfactory system. 1: Olfactory bulb 2: Mitral cells 3: Bone 4: Nasal epithelium 5: Glomerulus (olfaction) 6: Olfactory receptor cells

  • Thalamus

    • The thalamus is connected to the hippocampus via the mammillothalamic tract.
    • In particular, every sensory system (with the exception of the olfactory system) has a thalamic nucleus that receives sensory signals and sends them to the associated primary cortical area.

  • Sensory and Motor Tracts

    • The spinothalamic tract is a somatosensory tract and the corticospinal tract is a motor tract.
    • The spinothalamic tract is a sensory pathway originating in the spinal cord.
    • The types of sensory information transmitted via the spinothalamic tract are described as affective sensation.
    • The corticospinal tract conducts impulses from the brain to the spinal cord.
    • The corticospinal tract is made up of two separate tracts in the spinal cord: the lateral corticospinal tract and the anterior corticospinal tract.

  • Organization of Motor Neuron Pathways

    • These are the upper motor neurons of the corticospinal tract.
    • They then descend as the lateral corticospinal tract.
    • These are the rubrospinal tract, the vestibulospinal tract, the tectospinal tract, and the reticulospinal tract.
    • The function of lower motor neurons can be divided into two different groups: the lateral corticospinal tract and the anterior corticalspinal tract.
    • Included in the diagram are the following motor pathways: corticospinal tracts (pyramidal tract), and extrapyramidal tracts (tectospinal tract not delineated).

  • Somatic Sensory Pathways to the Cerebellum

    • Both tracts involve two neurons.
    • The dorsal spinocerebellar tract does not decussate, or cross sides, at all through its path.
    • This is one of the few afferent tracts through the superior cerebellar peduncle.
    • The dorsal spinocerebellar tract (also called the posterior spinocerebellar tract, Flechsig's fasciculus, or Flechsig's tract) conveys inconscient proprioceptive information from the body to the cerebellum.
    • This tract involves two neurons and ends up on the same side of the body.

  • Anatomy of the Digestive System

    • The upper gastrointestinal tract consists of the esophagus, stomach, and duodenum.
    • The lower gastrointestinal tract includes most of the small intestine and all of the large intestine .
    • It contains the plicae circulares and villi to increase the surface area of that part of the GI Tract.
    • The ligament of Treitz is sometimes used to divide the upper and lower GI tracts.
    • This image shows the position of the small intestine in the gastrointestinal tract.

  • Overview of the Cerebrum

    • The cerebrum contains the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb.
    • The frontal lobe is located at the front of the brain, over the eyes, and contains the  olfactory bulb.
    • The olfactory sensory system is unique in that neurons in the olfactory bulb send their axons directly to the olfactory cortex, rather than to the thalamus first.
    • Damage to the olfactory bulb results in a loss of the sense of smell.
    • The olfactory bulb also receives "top-down" information from such brain areas as the amygdala, neocortex, hippocampus, locus coeruleus, and substantia nigra.

  • Mucosa

    • The mucosa is the innermost layer of the gastrointestinal (GI) tract, composed of simple epithelium cells.
    • It is the absorptive and secretory layer of the GI tract.
    • The GI tract is composed of four layers.
    • The mucosae (singular: mucosa) are highly specialized in each organ of the gastrointestinal tract, in order to deal with the different digestive tract conditions.
    • Describe the structure and function of the mucosa of the GI tract