Researchers are getting closer to understanding how mature sensory neurons
are generated from olfactory stem cells, an understanding that's key for an eventual stem cell therapy to restore function.
The sensory systems contain highly specialized sensory neurons
that send signals to the brain about both the type of stimulus and the strength of the stimulus.
Contraction of muscle relieves the stretch on the muscle spindle such that the unloaded muscle spindle and its sensory neuron
stop sending action potentials (information indicating muscle length) to the central nervous system.
1] consisted of a mixture of sensory neurons
and nerve ring interneurons, whilst [S.
Thus, morphological criteria alone allow identification of six distinct subpopulations of DRG neurons in the fight microscope, although further studies are required to determine whether they correspond to physiologically different subpopulations of sensory neurons
This pattern change in the serial firing of the sensory neuron
is at the very bottom of the sensory hierarchy.
These changes to sensory neuron
firing properties contribute to increased reflex responses produced by various forms of learning, including dishabituation, sensitization (both long-term and short-term forms) and classical conditioning (see reviews by Byrne et al.
To date, both physiological analyses and morphological investigations separately have supported the hypothesis that each peripheral process of a primary sensory neuron
has just one type of mechanoreceptor.
Several studies have shown that the non-NMDA glutamate receptor antagonists DNQX (6,7-dinitroquinoxaline-2,3-dione) and CNQX (6-cyano-7-nitroquinoxaline-2,3-di-one) block sensory neuron
transmission in invertebrates (Dale and Kandel, 1993; Trudeau and Castellucci, 1993; Conrad et al.
Pain information enters the body through nerve endings (actually the tips of axons) in the skin or muscle and travels to a sensory neuron
(Figure 1: Neuron "A") in a small bundle of nerve tissue, the dorsal root ganglion, which is attached to the spinal cord.
Their passive electrical model of insect olfactory sensilla suggests that the amplitude of the transmembrane receptor potential is increased in a sensory neuron
whose sensitivity to a particular chemical stimulus is greater than that of its immediate neighbor.
The cell body of the spinal sensory neuron
is connected to this axon via a process that does not normally send sensory information.
The facilitation is also larger and longer lasting if the presynaptic sensory neuron
fires action potentials just before the serotonin application, analogous to classical conditioning (Eliot et al.
1986; Kandel, 2001), long-term synaptic facilitation (LTF) at Aplysia sensorimotor connections can be synapse-specific and can occur preferentially at selected synapses of a given siphon sensory neuron
(SN), relative to other connections of the same cell (Clark and Kandel, 1993; Gooch and Clark, 1997; Martin et al.
We found clear changes in olfactory sensory neuron
responses to odours for those 60 and up," said Professor Diego Restrepo, Ph.