neural impulse

(noun)

The signal transmitted along a nerve fiber, either in response to a stimulus (such as touch, pain, or heat), or as an instruction from the brain (such as causing a muscle to contract).

Related Terms

Examples of neural impulse in the following topics:

  • Stages of the Action Potential

    • Neural impulses occur when a stimulus depolarizes a cell membrane, prompting an action potential which sends an "all or nothing" signal.
    • Neural impulses from sensory receptors are sent to the brain and spinal cord for processing.
    • After the brain has processed the information, neural impulses are then conducted from the brain and spinal cord to muscles and glands, which is the resulting motor output.
    • In addition, some poisons and drugs interfere with nerve impulses by blocking sodium channels in nerves.
    • Reuptake refers to the reabsorption of a neurotransmitter by a presynaptic (sending) neuron after it has performed its function of transmitting a neural impulse.

  • Introduction to Sensation

    • ., light) into neural impulses.
    • These neural impulses enter the cerebral cortex of the brain, which is made up of layers of neurons with many inputs.
    • This fMRI chart shows some of the neural activation that takes place during sensation.

  • Perceiving Depth, Distance, and Size

    • Visual stimuli enter as light through the photoreceptors in the retina, where they are changed into neural impulses.
    • These impulses travel through the central nervous system, stop at the sensory way-station of the thalamus, and then are routed to the visual cortex.

  • Neural Networks

    • A neural network (or neural pathway) is the interface through which neurons communicate with one another.
    • These networks consist of a series of interconnected neurons whose activation sends a signal or impulse across the body.
    • The basic kinds of connections between neurons are chemical synapses and electrical gap junctions, through which either chemical or electrical impulses are communicated between neurons.
    • A neural network (or neural pathway) is the complex interface through which neurons communicate with one another.
    • Neurons interact with other neurons by sending a signal, or impulse, along their axon and across a synapse to the dendrites of a neighboring neuron.

  • A History of Theories of Consciousness

    • Theories of consciousness include developmental, cultural, neural, computational, and moral perspectives.
    • Much of what is stored in the unconscious is thought to be unpleasant or conflicting; for example, sexual impulses that are deemed unacceptable. 
    • Neuropsychologists view consciousness as ingrained in neural systems and organic brain structures.
    • A major part of the modern scientific literature on consciousness consists of studies that examine the relationship between the experiences reported by subjects and the activity that simultaneously takes place in their brains—that is, studies of the neural correlates of consciousness.

  • Psychosurgery

    • Psychosurgery, a group of procedures aimed at disrupting neural pathways, has declined over the years due to better psychiatric medications.
    • Psychosurgery is a drastic step typically only taken in the absence of any other successful treatment (and sometimes not even then), because it is a major challenge to remove harmful tissue without impacting the brain tissue necessary to retain full neural function.
    • In deep-brain stimulation (DBS), a device like a pacemaker is implanted into a part of the brain to send electrical impulses to that area of the brain.
    • Psychiatric medications also are able to provide effective treatment in a number of other ways, such as stimulating neural pathways.

  • Arousal Theory of Motivation

    • While drive-reduction theory focuses primarily on biological needs as motivators, arousal theory examines the influence of the neural transmitter dopamine as a motivator in the body.
    • Traits like impulsivity and sensation-seeking predispose people to engage in certain behaviors.
    • Temperament is defined as an individual's basic way of interacting and includes aspects like frustration tolerance (i.e., the ability to withstand frustrating situations without getting upset), delay of gratification, and inhibition vs. impulsivity.
    • Fulfilling the impulse brings about a physiological reward similar to the rat pressing the button.
    • Likewise, someone who is very impulsive and uninhibited might be very motivated to go buy a car on a moment's notice, as compared with someone who is very inhibited and has difficulty taking action.

  • The Endocrine System and Hunger

    • It involves neural signals from the GI tract, blood levels of nutrients, and GI-tract hormones.
    • Individuals suffering from starvation may experience irritability, lethargy, impulsivity, hyperactivity, and more apathy over time.

  • Audition: Hearing, the Ear, and Sound Localization

    • The function of the cochlea is to transform mechanical sound waves into electrical or neural signals for use in the brain.
    • These hair cells transform the fluid waves into electrical impulses using cilia, a specialized type of mechanosensor.
    • Hair cells in the cochlea perform the transduction of these sound waves into afferent electrical impulses.

  • Introducing the Neuron

    • An axon, at its most basic, is a tube-like structure that carries an electrical impulse from the cell body (or from another cell's dendrites) to the structures at opposite end of the neuron—axon terminals, which can then pass the impulse to another neuron.
    • The specialized structure and organization of neurons allows them to transmit signals in the form of electric impulses from the brain to the body and back.
    • This is the basic chain of neural signal transmission, which is how the brain sends signals to the muscles to make them move, and how sensory organs send signals to the brain.