How is sensitivity defined? Hypersensitivity, HSP: what is it? Usable Sensitivity

vivek_jonam

Why is the sensor sensitivity called "ISO"?

I was curious to know how the term "ISO" was coined to refer to the sensitivity of the image sensor. Is there any reason or circumstance that contributed to the name "ISO"?

Also, does ISO have a literal extension?

If it refers to the organization of ISO, why is sensitivity simply called "ISO"? Is there another official name for sensor sensitivity?

jrista ♦

Just a note. When it comes to the "sensitivity" of digital sensors, the term "sensitivity" in this context is actually a bit of a misnomer. The digital sensor is a fixed linear analog device. He always has the same real sensitivity. When you set the ISO setting to a higher level, all it really does is decrease the maximum saturation point. The sensor doesn't detect any more light... it detects the same thing, so it's still just as "sensitive". It's just that instead of pure white occurring at, say, 40,000 electrons per pixel (ISO 100), it happens at 20,000 electrons (ISO 200) or 10,000 electrons (ISO 400), etc.

RBerteig

The three official ISO languages ​​are English, French and Russian. The organization's logos, in its two official languages, English and French, include the word ISO, and it is usually referred to by this abbreviated name. The organization declares that ISO is not an abbreviation or initialism of the organization's full name in any official language. [Citation source] Recognizing that his initials will be different in different languages, the organization adopted ISO, based on the Greek word isos (ἴσος, meaning equal), as a universal shortened form of his name. However, one of the founding delegates, Willy Kuerth, recalled the original naming question with the comment: "I recently read that the name ISO was chosen because 'iso' is a Greek term meaning 'equal'." London! "

ISO has written many technical standards, technical reports, technical specifications, etc. Each of these is assigned an ISO number. The three standards that apply to film speed are ISO 6, ISO 2240 and ISO 5800. Over time, film speed was referred to as "ISO" because the number used to describe film speed conformed to those ISO standards.

In digital cameras, "ISO" continued to be used as a way of expressing a digital camera's sensitivity to light at various amplification levels of analog electrical signals coming from dots of pixels on the camera's sensor. The International Organization for Standardization has released new standards for the light sensitivity of digital sensors. In theory, the ISO setting on your 400 digital camera should result in an exposure equivalent to that of ISO 400 film. Film speed varied slightly from one film manufacturer to another. A film that has an actual cost, such as 388 based on ISO standards, will be marketed as "400 speed". Likewise, most digital cameras differ slightly at different ISO settings from the exact standard. At least one company, DxO, publishes test results for many cameras. If you follow the link and select the "Measurements" tab, you'll see that the actual ISO can vary by 1/2 stop for the three entry-level camera bodies I've chosen.

The main thing to know about ISO when photographing is that the higher the ISO number you choose, the "noisier" your image will be. Noise is an electrical signal from a pixel that was caused by nothing but light falling on it. When the signal from the sensor is amplified to increase the ISO, this noise is also amplified. Because your camera (or software for processing on your computer) processes the signals from your sensor, certain measures are applied to smooth out the noise. Most cameras have settings that let you choose how much noise reduction you want to apply to the pictures you take. The downside to heavily using noise reduction is that it also reduces the sharpness of the image at the pixel level. Therefore, it is recommended to shoot at the lowest ISO speed that allows you to select the desired combinations of aperture and shutter speed. On the other hand, a blurred image due to a too slow shutter speed cannot be corrected by processing. A noisy image that has stopped your subject moving can be dealt with to a certain extent.

vivek_jonam

1 for "Over time, film speed became known as 'ISO'"

damn truths

Michael Clark

Official name for English language- International Organization for Standards. In French it is "International Organization for Normalization". Neither version orders the equivalent English words in the same way as "ISO". "ISO" was rumored to be short for the Greek word "isos", which means "equal".

Observing creative personalities, it is impossible not to note their increased sensitivity. Sensitivity gives rise to emotional experiences, it gives rise to a storm of emotions, it is she who allows the artist to penetrate the secrets of the world and show their reflection in his works.

In the scientific literature, such a subtle structure of the soul is called sensitivity.

Sensitivity- a personality trait, expressed in increased sensitivity and vulnerability, self-doubt, increased conscientiousness and a tendency to doubt, fixation on one's experiences.
Big Medical Dictionary

Our feelings are the most important and complex aspect of spiritual life. These are not just fleeting sensations. This is the experience gained through our observation, mindfulness and receptivity. Sensitivity to art, objects around us, people with whom we communicate, undoubtedly enriches our inner world, making us spiritually filled and open.

• Sensitivity is a bright emotion that paints our life in bright colors.
• Sensitivity is empathy and empathy.
• Sensitivity is the ability to perceive not so much rationally as emotionally.
• Sensitivity is the path to aesthetic pleasure.

Sensitivity Benefits

• Thanks to sensitivity, we comprehend the essence of what is happening to us.
• Thanks to sensitivity, we enrich our inner world and have the opportunity to build inner harmony.
• Sensitivity leads to the creation of unique and unforgettable works of art, as they come from the very depths of the soul.
• Our sensitivity allows aesthetic taste and artistic experiences to manifest.

Manifestations of sensitivity in everyday life

Sensitivity in Everyday life can manifest itself in completely different situations and often it can cause even greater virtues.

• A bright, hysterical performance by an actor or music rich in many emotional nuances make it possible for our sensitivity to manifest itself.
• Sensitivity, coupled with imaginative thinking, push many of us to express our experiences through art - poetry, painting, music.
• We show our sensitivity by empathizing with other people - close or unfamiliar. A sensitive person can always easily understand another person and share his emotions.
• It is sensitivity that makes us compassionate and sacrifice our time, means, and perhaps even our lives for other people.

How to develop sensitivity

Of course, we will talk about balance and the golden mean. Hypersensitivity implies too active rethinking of what is happening around. In a world full of stress, upheaval and selfishness, over-sensitivity can threaten our inner harmony. Therefore, cultivating sensitivity in oneself, it is necessary to find a philosophical approach to life.

It is best to develop sensitivity with the help of works of art - painting, music, literature. Try to understand the hero of the work, transfer his feelings to yourself and imagine how you would feel if you were in a similar situation. In world classical literature, the actions of heroes are often given a detailed explanation, so they can be used as a “practical guide” for a detailed analysis of the emotions of other people.

Be more attentive to the people around you. During a conversation with them, try to understand with the help of questions why they acted one way or another, how they felt at that moment.

Sensitivity is not easy to develop, but it will help you more easily find a common language with other people and build your relationship with them on a completely different, higher level.

Golden mean

Callousness

Sensitivity

Over-sensitivity

Popular expressions about sensitivity

To feel is not the same as to understand. - A.N. Afinogenov - Feelings are the brightest part of our life. - Balzac - You can be the master of your actions, but in feelings we are not free. - G. Flaubert - Feeling is the eve of the appearance of thought. - I.N. Pevtsov - You can feel strongly, vividly and fieryly and at the same time not be able to express your feelings. - V.G. Belinsky - Esquivel Laura / The Book of Feelings How and why is a feeling born and dying? Can it be expressed in words? Is there a way to overcome the terrible evil of our time - depression? To make the world around you happier? Find inner harmony? Here are just a few of the many questions that the peculiar Mexican writer ponders. And her answers are amazingly unexpected. Alexander Berzin / Developing Balanced Sensitivity: Practical Buddhist Exercises for Daily Life Achieving emotional balance or maintaining healthy relationships is never easy. However, for various reasons, we further complicate these problems. These problems include lack of sensitivity or insensitivity in some situations and disproportionate sensitivity or overreaction in others. The author, adapting the Buddha's methods for self-improvement to modern Western conditions, considers these problems in accordance with the peculiarities of Western cultural characteristics.

Sensitivity is the ability of a living organism to respond to various kinds of stimuli emanating from the external or internal environment. The study of sensitivity occupies an important place in determining the state of the nervous system of the body. At the same time, the problem of sensitivity is of great theoretical and philosophical significance and is connected with the theory of knowledge. Through the sensations underlying the sensitivity, arising as a result of exposure to various stimuli on the body, knowledge of the surrounding world occurs, which was formulated in the brilliant statements of V. I. Lenin, who emphasized that “... sensation is really a direct connection of consciousness with the outside world, is the transformation of the energy of external stimulus into a fact of consciousness. (V. I. Lenin, Collected works, ed. 5, vol. 18, p. 46.)

For understanding the physiological mechanisms of sensitivity, the doctrine of the analyzer is of particular importance (see), in which the peripheral section is distinguished - the receptor apparatus, the conductor and brain sections, mainly the cortical end of the analyzer. Sensitivity is based on the dynamic interaction of various parts of the system of one or another analyzer. In its peripheral final body, a so-called receptor (see), the impulse extending in TsNS originates.

The main biological significance of receptor devices lies in the fact that they are able to respond with the appearance of excitation under the action of stimuli, being a source of appropriate sensations - pain, tactile, temperature, etc. For the sensation to occur, it is necessary that the stimuli that set the receptor have sufficient intensity. The minimum force of irritation that can cause a sensation is called the threshold force, the threshold. The higher the intensity and the longer the duration of the stimulation, the faster the threshold is overcome, the more intense the sensation. The excitability of the receptor is determined not only by the absolute intensity of stimulation, but also by the number of simultaneously stimulated receptors or the quality of their repeated irritations - the law of summation of receptor irritations. On the other hand, the excitability of the receptor and its threshold also depend on the influence of the central nervous system, as well as on sympathetic innervation. Normally, the threshold height of different receptors is not the same.

For the correct and objective analysis of sensitive stimulation, including that part of it that has no equivalent in the form of sensation, the possibility of registering electrical potentials accompanying the appearance of impulses in the receptor apparatus in connection with the corresponding irritation is of great importance.

Receptors, depending on their location, are divided into somato- and visceroreceptors. The former include exteroreceptors, which are divided into distance receptors that perceive irritation at a distance (for example, visual, auditory, etc.), contact receptors that perceive irritation in direct contact with an external object and are located in the skin and mucous membranes, and proprioreceptors - in deep tissues ( muscles, tendons, joints), as well as in the ear labyrinths. Visceroreceptors are the final sensory apparatuses of various visceral organs, vessels, etc. Histological studies show the originality and complexity of the structure of the final sensory apparatuses. These features of the peripheral receptor apparatus served as starting points for the clinical classification of sensitivity.

At the heart of this classification, most authors note the quality, nature of the irritation (prick, heat, touch, etc.), the subjective sensations associated with this irritation (pain, etc.), the area of ​​\u200b\u200birritation (skin, muscles, etc.). Accordingly, separate types are distinguished 4.1. Skin, or exteroceptive, superficial sensitivity - pain, tactile, temperature (heat and cold). Varieties of these types of sensitivity: electrocutaneous - sensations caused by various types electric current; the feeling of itching is a kind of tactile sensitivity; a sense of humidity - hygresthesia (it is based on a combination of tactile sensation with temperature). 2. Proprioceptive, deep, sensitivity - bathiesthesia. These include musculo-articular sensitivity or sensitivity of body position in space; vibration - pallesthesia; feeling of pressure - baresthesia. 3. Interoceptive, vegetative-visceral, covering sensitivity internal organs, vessels, etc. Separately, complex types of sensitivity are distinguished, where more complex analytical processes predominate - discriminatory, two-dimensional-spatial, stereognosis. According to Geda's classification (see Geda zones), all sensitivity should be divided into protopathic, associated with the thalamus, - more primitive, ancient, and epicritical - newer, more complex, determined by the cerebral cortex. Ged's positions are not supported by modern data, although these terms are used in the clinic.

Specific differentiation of sensitivity is associated with the structural and physiological characteristics of the peripheral nerve fiber. Sensitive impulses arising in the receptor apparatus are carried out by fibers of different structure at different speeds depending on the severity of the myelin layer and the different frequencies of the electrical potential oscillations noted in this case. Structural and physiological differences also reflect the different functional significance of nerve fibers. Thus, group A fibers with a thick myelin sheath, carrying fast impulses, conduct deep and tactile sensitivity. Group B fibers with a thin myelin sheath, with slower impulses, conduct pain, temperature and tactile sensitivity and non-myelinated C fibers, slowly conducting impulses, diffuse non-localized pain.

All impulses arising in the peripheral apparatus of general sensitivity enter mainly through the posterior roots of the spinal cord into the central nervous system, where sensations arise. The emergence of any sensation is determined by the process of afferentation, the propagation of a specific impulse from the corresponding receptor along certain pathways. In response to this or that irritation, all departments of the corresponding analyzer are activated, and the usual sensation, according to the type of sensitivity, is always the result of a complex interaction of various mechanisms up to cortical ones, which, according to I.P. Pavlov, determine the analysis and synthesis of incoming impulses. Great importance for a correct understanding of the central mechanisms of sensitivity, it takes into account its versatile interactions with the reticular formation, this kind of ascending, activating, so-called non-specific system of the brain. Important, that reticular formation It also exerts downward regulatory influences on the peripheral receptor apparatus and the process of afferentation in sensory pathways. Thus, sensitivity, which was previously considered only as a result of one-sided afferentation, passive conduction of receptor excitation in the central direction, acts as a complex system with double bonds, with an active effect on the flow of sensory impulses and constant regulation of the level of excitability of various localized links of sensitivity through facilitating and inhibitory influence. All these data create certain prerequisites for a correct assessment of the cortical-subcortical relationships in the mechanism of sensitivity.

Sensitivity is a property of a living organism, expressed in the perception of stimuli from the external environment and from its own tissues and organs. There are exteroceptive sensitivity (superficial), proprioceptive sensitivity (deep) and interoceptive, or vegetative-visceral, sensitivity (from internal organs, blood vessels, etc.). There are also complex types of sensitivity (stereognosis, etc.). The perception of irritations in humans exists only if the receptor is inextricably linked, i.e., the peripheral part of the sensitive analyzer (see), with its cortical section. The connection between these sections of the analyzer goes through a three-link chain of neurons.

Depending on which of the neurons is disturbed, one or another type of sensitivity disorder will be clinically observed, according to the nature of which the damage is diagnosed. For such a determination, it is necessary to know the anatomical course of sensitive pathways and the distribution of peripheral neurons.

Each segment of the spinal cord is connected through the posterior roots with a strictly corresponding skin segment. Irritations from the skin segments go along different peripheral nerves (for example, the cervicobrachial and lumbosacral plexus), therefore, with damage to the posterior roots, the pattern of loss of sensitivity differs from the loss of sensitivity observed with damage to the peripheral nerves (Fig.). This gives the right to talk about a sensitivity disorder of the peripheral and radicular type, that is, about the blockade of nerve impulses in the peripheral nerve trunk or in one or another posterior root of the spinal cord, which is noted with neuritis,. With the radicular type of loss of sensitivity, the segmental type of loss of sensitivity coincides geographically with damage to the posterior horn of any segment of the spinal cord. However, they are qualitatively different, since with the segmental type, sensitivity according to the dissociated type drops out, that is, only pain and temperature sensitivity, and deep sensitivity is preserved. This is due to the fact that the fibers of the posterior root are separated upon entering. The fibers that transmit impulses from the muscles and joints, without entering the posterior horn, go up along the posterior columns in order to switch to the second neuron at the level of the medulla oblongata, which makes the transition to the opposite side and reaches the thalamus, from where the third neuron delivers the impulse to the posterior and anterior central gyri of the cerebral hemispheres. Thus, deep sensitivity is transmitted along the back pillars of the side of the same name. The posterior root fibers, through which pain and temperature sensitivity is transmitted, enter the gelatinous Roland substance of the posterior horn of the same segment of the spinal cord, where they switch to the second neuron, which, rising upward, passes in front of the central canal of the spinal cord to the opposite side and goes along the lateral column of the spinal cord. the brain, forming the spinothalamic pathway, reaches the thalamus opticus, and then, as part of the third neuron, the impulses reach the posterior central gyrus, i.e., the cortical part of the skin analyzer. Thus, the segmental type of sensitivity disorder, or otherwise the posterior type of sensitivity disorder, will be detected in cases where the patient has pain and temperature sensitivity on certain skin segments, and the deep one is not disturbed. So, for example, when (see), such areas of loss of sensitivity in the form of a jacket or half-jacket are well known, and patients in these parts of the body often have traces of previously painless burns.

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reception- the ability of the body to perceive information from the external and internal environment. The primary perception of all stimuli in the human body is carried out receptors- specific cells that perceive the effects of external and changes in the internal environment of the body.

Sensitivity- the ability of the body to perceive information (stimuli) from the external and internal environment and respond to it with differentiated forms of reactions.

Analyzer- a functional association of structures that performs the perception and analysis of information (receptor - pathways - cortical center).

2. Sensitivity classification:

Kinds sensitivity by modality:

1)Simple

- exteroception:distant- hearing, vision; contact- pain, tactile, temperature, feeling of pressure (pyesthesia), taste; mixed(?) – sense of smell

- interoception(chemo-, baro-, osmoreceptors),

- proprioception(joint-muscular feeling - kinesthesia, feeling of movement of the skin fold - dermatokinesthesia, vibration - seismoesthesia, sense of weight - baroesthesia).

2)Complex

- localization(topesthesia),

- discriminatory,

- two-dimensional-spatial(graphesthesia, dermatolexia),

- three-dimensional-spatial(stereognosis).

Types of sensitivity according to the level of information processing:

1)protopathic(thalamic or vital) - perceives gross influences that threaten the life of the body - fibers of type B and C.

2)epicritical(cortical, gnostic) - provides subtle recognition and differentiation of various influences - fibers of type A.

Gued-Scherer law(1905) - in the process of regeneration of the sensory nerve, first the restoration of protopathic, and then epicritical sensitivity occurs.

3. Peripheral components of the sensitivity system:

Types of contact exteroreceptors:

1)Painful: nociceptor - nociceptive system (see below).

2)Temperature: warm - Ruffini's ending and cold - Bulb Krause.

3)Tactile(1 type of receptors - with small, delineated fields) : Merkel disc (slowly adapting) and Meissner corpuscle (rapidly adapting).

4)pressures and weights(type 2 receptors - with extensive fields) : the body of Golgi-Mazzoni (slowly adapting) and the body of Vater-Pacchini (quickly adapting).

5) vibrations- periosteal receptors

Types proprioceptors (for details, see the topic "Reflex-motor sphere"):

1)muscle spindles 1 and 2 types.

2)tendon receptors(Golgi body).

Types sensitive fibers:

1)thick myelin type A-alpha(40-50 m/s) - proprioception;

2)thick myelin type A-beta(30-40 m/s) - tactile;

3)thick myelin type A-gamma(20-30 m/s) - pressure;

4)thin myelin type B(10-14 m/s) - pain and temperature;

5)unmyelinated type C(2 m/s) - pain (protopathic).

Sensitivity: morphophysiology

1. General features of the three-neuronal pathways of superficial and deep sensitivity

First the neuron is located in the spinal (cranial) node.

axons second neurons cross over.

Third neuron located in the ventrolateral complex of the thalamus, its axon - thalamocortical path passes through the posterior third of the posterior leg of the internal capsule and the radiant crown, ends in the posterior central gyrus and the upper parietal region.