Perception is the initial stage of higher nervous activity. Through perception, external and internal stimuli become facts of consciousness, reflecting the individual properties of objects and events.

Irritant – “feeling” perception ” view.

Sensation is the simplest psychic process, consisting in the reflection of individual properties of objects and phenomena, arising in the process of their impact on the senses.

Perception is the psychic process of reflecting objects and phenomena as a whole, in the aggregate of their properties.

Representation is an image of an object or phenomenon reproduced in consciousness on the basis of past impressions. Depends on the will of the individual.

Symptoms of perceptual disorders.

Hyperesthesia – hypersensitivity to stimuli of normal strength. Often found in exogenous organic lesions of the Central nervous system, manic States.

Hypoesthesia (hypoesthesia) – reduced sensitivity to stimuli. It is often observed in disorders of consciousness, organic disorders of the Central nervous system, depressive States. Anesthesia – extreme hypoesthesia. Painful mental anesthesia-subjectively seeming very painful weakening of any kind of sensitivity, due to a decrease in emotional tone (anaesthesia psychica dolorosa)

Agnosia – non-recognition of the stimulus, occurs in organic lesions of the Central nervous system, hysterical sensitivity disorders.

Paresthesia is a subjective feeling arising without stimulus (tingling, pins and needles, numbness, etc.). Disorders have localization, clearly limited by zones of innervation. Are a symptom of neurological disorder.

Senestopatii (the illusion of shared feelings) – uncertain, difficult to localize, unpleasant, painful bodily sensations. They have unique descriptions patients (retraction, pouring, peeling, turning, drilling, etc.). Sensations have no real basis ,are “non-objective”, do not correspond to zones of innervation. Often found in the structure of senesta – hypochondriac syndrome (senestopatii + the idea of “imaginary” disease + affective disorder), schizophrenia, depression.

Illusions – an erroneous perception of actual objects and events.

Officegenie illusions occur when fear, anxiety, depression, ecstasy. Their appearance contributes to the fuzzy perception of the environment (weak lighting, slurred speech, noise, distance of the object).

Physical – associated with the characteristics of physical phenomena (spoon in a glass of water seems to curve).

Pareidolic illusions – visual illusions in which patterns, cracks, tree branches, clouds are replaced by images of fantastic content. Observed in delirium, intoxication by psychokinetically.

Etatism – sensually vivid picture immediately preceding sensations (especially memory).