sensory system

Information about sensory system

See also sense
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The human eye is the first element of a sensory system: in this case, vision, for the visual system.
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Typical sensory system: the visual system, illustrated by the classic Gray's FIG. 722– This scheme shows the flow of information from the eyes to the central connections of the optic nerves and optic tracts, to the visual cortex. Area V1 is the region of the brain which is engaged in vision.


A sensory system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory receptors, neural pathways, and parts of the brain involved in sensory perception. Commonly recognized sensory systems are those for vision, hearing, somatic sensation (touch), taste and olfaction (smell).

The receptive field is the specific part of the world to which a receptor organ and receptor cells respond. For instance, the part of the world an eye can see, is its receptive field; the light that each rod or cone can see, is its receptive field.[1] Receptive fields have been identified for the visual system, auditory system and somatosensory system, so far.

Stimulus

Sensory systems code for four aspects of a stimulus; type (modality), intensity, location, and duration. Certain receptors are sensitive to certain types of stimuli (for example, different mechanoreceptors respond best to different kinds of touch stimuli, like sharp or blunt objects). Receptors send impulses in certain patterns to send information about the intensity of a stimulus (for example, how loud a sound is). The location of the receptor that is stimulated gives the brain information about the location of the stimulus (for example, stimulating a mechanoreceptor in a finger will send information to the brain about that finger). The duration of the stimulus (how long it lasts) is conveyed by firing patterns of receptors.

Modality

A stimulus modality (sensory modality) is a type of physical phenomenon that can be sensed. Examples are temperature, taste, sound, and pressure. The type of sensory receptor activated by a stimulus plays the primary role in coding the stimulus modality.

In the memory-prediction framework, Jeff Hawkins mentions a correspondence between the six layers of the cerebral cortex and the six layers of the optic tract of the visual system. The primary visual cortex has areas labelled V1, V2, V3, V4, V5, MT, IT, etc. Thus Area V1 mentioned below, is meant to signify only one class of cells in the brain, for which there can be many other cells which are also engaged in vision.

Hawkins lays out a scheme for the analogous modalities of the sensory system. Note that there can be many types of senses, some not mentioned here. In particular, for humans, there will be cells which can be labelled as belonging to V1, V2 A1, A2, etc.:

V1 (vision)

Visual Area 1, or V1, is used for vision, via the visual system to the primary visual cortex. See the illustration above.

A1 (auditory - hearing)

Auditory Area 1, or A1, is for hearing, via the auditory system, the primary auditory cortex.

S1 (somatosensory - touch)

Somatosensory Area 1, or S1, is for touch and proprioception in the somatosensory system. The somatosensory system feeds the Brodmann Areas 3, 1 and 2 of the primary somatosensory cortex. But there are also pathways for proprioception (via the cerebellum), and motor control (via Brodmann area 4).

G1 (gustatory - taste)

Gustatory Area 1, or G1, is used for taste.

O1 (olfactory - smell)

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The olfactory bulbs are the most highly developed part of this Tyrannosaurus rex's brain.
Olfactory Area 1, or O1, is used for smell. In contrast to vision and hearing, the olfactory bulbs are not cross-hemispheric; the right bulb connects to the right hemisphere and the left bulb connects to the left hemisphere.

Human sensory system

The Human sensory system consists of the following sub-systems: Human sensory receptors are:
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Nervous system
Central nervous system (Brain, Spinal cord) • Peripheral nervous system • Somatic nervous system • Autonomic nervous system (Sympathetic, Parasympathetic) • Enteric nervous system • Sensory system
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Nervous system: Sensory systems/sense
Special sensesVisual system/Visual perception • Auditory system/Hearing • Chemoreception (Olfactory system/Olfaction • Gustatory system/Taste)
Somatosensory systemNociception • Thermoreception • Vestibular system • Mechanoreception (Pressure, Vibration, Proprioception)
OtherSensory receptor
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Global structure in Systems, Systems sciences and Systems scientists
Categories
SystemsBiological system Complex system Complex adaptive system Conceptual system Cultural system Dynamical system Economic system Ecosystem Formal system Global Positioning System Human organ systems Information systems Legal system Metric system Nervous system Non-linear system Operating system Physical system Political system Sensory system Social system Solar System System Systems of measurement
Fields of theoryChaos theory Complex systems Control theory Cybernetics Holism in science Sociotechnical systems theory Systems biology Systems dynamics Systems ecology Systems engineering Systems theory Systems science
Systems scientistsRussell L. Ackoff William Ross Ashby Gregory Bateson Ludwig von Bertalanffy Kenneth E. Boulding C. West Churchman Heinz von Foerster Charles Franois Jay Wright Forrester Ralph W. Gerard Debora Hammond George Klir Niklas Luhmann Humberto Maturana Donella Meadows Mihajlo D. Mesarovic Howard T. Odum Talcott Parsons Ilya Prigogine Anatol Rapoport Francisco Varela John N. Warfield Norbert Wiener

References

1. ^ Kolb & Whishaw: Fundamentals of Human Neuropsychology (2003)
Senses are the physiological methods of perception. The senses and their operation, classification, and theory are overlapping topics studied by a variety of fields, most notably neuroscience, cognitive psychology (or cognitive science), and philosophy of perception.
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nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. Prominent parts of a nervous system include neurons and nerves, which are used in coordination.
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Senses are the physiological methods of perception. The senses and their operation, classification, and theory are overlapping topics studied by a variety of fields, most notably neuroscience, cognitive psychology (or cognitive science), and philosophy of perception.
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In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. In response to stimuli the sensory receptor initiates sensory transduction by creating graded potentials or action potentials in the same cell
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A neural pathway is a neural tract connecting one part of the nervous system with another, usually consisting of bundles of elongated, myelin insultated neurons, known collectively as white matter.
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In animals, the brain or encephalon (Greek for "in the skull"), is the control center of the central nervous system, responsible for behavior. The brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing,
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In psychology, visual perception is the ability to interpret visible light information reaching the eyes which is then made available for planning and action. The resulting perception is also known as eyesight, sight or vision.
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Hearing (or audition) is one of the traditional five senses, and refers to the ability to detect sound. In humans and other vertebrates, hearing is performed primarily by the auditory system: sound is detected by the ear and transduced into nerve impulses that are perceived
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Somatic sensation consists of the various sensory receptors that trigger the experiences labelled as touch or pressure, temperature (warm or cold), pain (including itch and tickle), and the sensations of muscle movement and joint position including posture, movement, and facial
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Taste (or more formally, gustation) is a form of direct chemoreception and is one of the traditional five senses. It refers to the ability to detect the flavor of substances such as food and poisons.
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Olfaction (also known as olfactics) refers to the sense of smell. This sense is mediated by specialized sensory cells of the nasal cavity of vertbrates, and, by analogy, sensory cells of the antennae of invertebrates.
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The receptive field of a sensory neuron is a region of space in which the presence of a stimulus will alter the firing of that neuron. Receptive fields have been identified for neurons of the auditory system, the somatosensory system, and the visual system.
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Rod may mean:
  • Rod (geometry), a straight and slender stick; a wand; a cylinder; hence, any slender bar
  • Rod cell, a cell found in the retina that is sensitive to light/dark (black/white)
  • Rod (unit), an Imperial unit of length, also known as the pole or

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Cone (from the Greek κώνος, Latin conu) is a basic geometrical shape. It may also refer to:
  • Cone (software), a text-based e-mail client and news client for Unix-like operating systems.

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The receptive field of a sensory neuron is a region of space in which the presence of a stimulus will alter the firing of that neuron. Receptive fields have been identified for neurons of the auditory system, the somatosensory system, and the visual system.
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The visual system is the part of the nervous system which allows organisms to see. It interprets the information from visible light to build a representation of the world surrounding the body.
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The auditory system is the sensory system for the sense of hearing.

Ear

Main article: Ear

Outer ear

Main article: Outer ear

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Somatic sensation consists of the various sensory receptors that trigger the experiences labelled as touch or pressure, temperature (warm or cold), pain (including itch and tickle), and the sensations of muscle movement and joint position including posture, movement, and facial
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In physiology, a stimulus is a detectable change in the internal or external environment. When a stimulus is applied to a sensory receptor, it elicits or influences a reflex via stimulus transduction. A stimulus is often the first component of a homeostatic control system.
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A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. There are four main types in the glabrous skin of humans: Pacinian corpuscles, Meissner's corpuscles, Merkel's discs, and Ruffini corpuscles.
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An action potential is a "spike" of electrical discharge that travels along the membrane of a cell. Action potentials are an essential feature of animal life, rapidly carrying information within and between tissues. They also occur in some plants.
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Stimulus modality also sensory modality is one aspect of a stimulus. There are many modalities: temperature, taste, sound, pressure. The type of sensory receptor activated by a stimulus plays the primary role in coding the stimulus modality.
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trillion fold).]]

Temperature is a physical property of a system that underlies the common notions of hot and cold; something that is hotter generally has the greater temperature. Temperature is one of the principal parameters of thermodynamics.
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Taste (or more formally, gustation) is a form of direct chemoreception and is one of the traditional five senses. It refers to the ability to detect the flavor of substances such as food and poisons.
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Sound is a disturbance of mechanical energy that propagates through matter as a wave (through fluids as a compression wave, and through solids as both compression and shear waves).
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Pressure (symbol: p) is the force per unit area applied on a surface in a direction perpendicular to that surface.

Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.
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In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. In response to stimuli the sensory receptor initiates sensory transduction by creating graded potentials or action potentials in the same cell
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The memory-prediction framework is a theory of brain function that was created by Jeff Hawkins and described in his book On Intelligence. This theory concerns the role of the human neocortex and its associations with the hippocampus and the thalamus in matching sensory
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Jeff Hawkins (born June 1, 1957 in Huntington, New York) is the founder of Palm Computing (where he invented the Palm Pilot)[1] and Handspring (where he invented the Treo).
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cerebral cortex is a structure within the vertebrate brain with distinct structural and functional properties. In non-living, preserved brains, the outermost layers of the cerebrum has a grey color, hence the name "grey matter".
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