Psychopathology of perception. Perceptual distortions.(II/III)

PERCEPTUAL DISTORTIONS

LWe call them perceptual distortions when, in the presence of a stimulus or object in the sensory field, we produce modifications in it, whether in its intensity, quality, form, or affective component. Not all perceptual distortions are pathological.

1. Changes in intensity:
   1. Hypoesthesia.
   2. Hyperesthesia.
   3. Dysesthesia.
2. Qualitative modifications:
   1. Synesthesia.
   2. Color alteration.
3. Modification in form:
   1. Dysmegalopsias.
   2. Disintegration of form.
4. Affective modifications on perception.

Quantitative modifications

• hypoesthesiaThis occurs when stimuli are perceived with low intensity or frequency. It can happen in depression, hysteria, emotional shock, self-harm, etc.
• Hyperesthesia: This is the opposite of the previous situation. It usually occurs in intense emotional situations or when attention is focused on the stimulus. There is often a direct relationship between anxiety and an increased feeling of it.
• dysesthesia: It is a general term that applies to any alteration of sensation when it is bothersome or painful.
• Hysterical anesthesia: Loss of sensitivity in hysterical disorders.

These perceptual changes can be psychological or organic.

Qualitative Modifications

• Synesthesia: It involves associating stimuli from different sensory organs. For example: seeing a sound or hearing a flower.
• Altered color perception: When an object or scene is perceived as a different color than it actually is. It has nothing to do with color blindness: yellow: xanthopsia; green: chloropsy, etc.

Modifications of the form

• Dysmegalopsia: This sensory phenomenon refers to changes that occur in the normal configuration of objects. Two main types are described: megalopsia (increase in size) and micropsy (decrease in size)
• Disintegration: It refers to the inability to integrate the parts of an object into a whole.
• Agglutination: The association of different perceptual elements in an object.

Affective modifications or abnormal characteristics of perception

Strangeness: It consists of the presence of a feeling of strangeness about situations or realities previously known by the subject.

Derealization: The environment is perceived as unreal. This is common in depersonalization.

Depersonalization: The strangeness arises with respect to one's own self, one's own body.

Metamorphopsia: Some authors include this phenomenon here. It consists of the alternating shrinking and enlargement of objects.

Bibliography

• C. Díez-Alegría Gálvez and S. Sánchez Quintero. Perception. In: I. Eguiluz and R. Segarra. Introduction to Psychopathology. An updated view. 2013. Barcelona. Edit-Med. Panamericana (2nd Ed)
• Fernando Sarráis (2016). Psychopathology. Navarra. EUNSA Publishing House

Next: Psychopathology of perception. Perceptual distortions