Human beings obtain information about the world around them through their senses. Sight, hearing, taste, smell and touch allow us to obtain information about the environment. Thus we can detect dangers, listen to an alarm that can alert us, detect that a food is not well preserved through taste and/or smell, feel the softness of some fabrics, enjoy music, the smell of flowers in spring, observe a painting exhibition, etc.
Sometimes, the sense organs are in perfect condition, but the information from the environment does not reach our brain correctly. One of the examples is asterognosia, an alteration that affects touch. In this Psychology-Online article, we talk to you about asterognosia: what it is, symptoms, causes and treatment.
Perception and agnosia
Information from the environment reaches our senses and stimulates them. Beyond sensation, our system perceives stimuli. What does it mean to perceive? The perception It is a cognitive, psychophysical and biological process through which we give meaning to the information that reaches our senses. The perceptual process allows us to interpret the information that comes to us through the senses.
The agnosia is the term with which we refer to the pathology of perception and consists of the inability to recognize stimuli and attribute meaning to them. Agnosias can be classified based on the sensory system that is affected. In this article, we tell you which ones exist.
What is astereognosia
Stereognosia consists of the ability to recognize objects by touch. If we ask a person to close their eyes and give them an object, this person will be able to recognize said object simply by touching it.
The meaning of astereognosia was initially described by Wernicke in 1885. It constitutes a perceptual pathology and refers to the inability to recognize objects through touch without the intervention of other perceptual modalities such as vision or hearing. Portellano, JA defines astereognosia as the inability to recognize physical qualities such as weight or size through touch and in the absence of hypoesthesia.
Types of astereognosia
There are different types of astereognosia. Specifically, this alteration can be primary or secondary:
- Primary asterognosia: caused by injuries to the primary somesthetic areas. It would, therefore, be a sensory disorder.
- Secondary asterognosia or asymbolia: would constitute the perceptual pathology itself. Their sensory capacity is perfectly preserved and the failure occurs when attributing meaning to the stimulus.
Symptoms of astereognosia
Astereognosia is not a diagnostic category. This is a perceptual failure that can appear as a consequence of brain lesions in specific areas and, therefore, would be a symptom in itself.
What are we going to see in a person with astereognosia? Think about situations in which you must recognize objects by touch, such as when searching in your purse, backpack, or pockets for a specific object, such as keys. So that a person with astereognosia knows if what they have taken are the keys must be guided by other perceptual modalities: move the object and check if it sounds like keys or take everything out of your pocket and help yourself with vision.
Causes of astereognosia
The lesions occurring in the associative somesthetic cortex They would be behind the appearance of astereognosia. The somesthetic cortex is located in the parietal lobe and is where the processing of tactile sensations is carried out, in addition to others such as proprioceptive, nocioceptive or thermoalgesic sensations. It is also related to the discrimination of touch, pain, temperature and kinesthetic sensitivity.
To be able to identify it better, in this article, you will see.
Treatment of astereognosia
The treatment of this type of agnosia will be determined by neuropsychological evaluation prior to being carried out by the professional. Based on the results obtained, an individual intervention strategy will be established and adapted to the case. We must take into account that it is possible that, as a result of the injury to certain areas, other difficulties may appear, so the treatment must respond to each of the alterations that the patient presents.
In general, the treatment of asterognosia will be aimed at cognitive rehabilitation through three strategies:
- Retraining of altered function: consists of the recovery of total or partial function through direct training of the ability to recognize objects tactilely. The professional will assess to what degree function can be recovered.
- Substitution: This strategy focuses on the other preserved cognitive functions, through which we will try to minimize the repercussions of the alteration. For example, in this case, we can rely on the recognition of objects through others such as sight or hearing.
- Compensation: This method requires the support of external signals. It is used when neither replacement nor recovery of function has been possible, so the person will rely on other resources and devices that help compensate for the cognitive damage.
This article is merely informative, at Psychology-Online we do not have the power to make a diagnosis or recommend a treatment. We invite you to go to a psychologist to treat your particular case.
If you want to read more articles similar to Astereognosia: what it is, symptoms, causes and treatmentwe recommend that you enter our category.
References
- Portellano, JA (2005) Introduction to neuropsychology. Madrid: McGraw Hill.
Bibliography
- Moreno Arroyo, MC and Andreu Periz, L. (2011). Neurological disorders: let’s review our knowledge. Nursing, 29 (2).
- Portellano, JA (2005) Introduction to neuropsychology. Madrid: McGraw Hill.