Historically, the first specialists in neuropsychology have argued that cognitive functions become dissociated (that is, they could be selectively altered due to brain damage) and that each is made up of different elements which in turn , also dissociate.
The above hypothesis, called “modularity of the mind”, Supports the idea that the neurological information processing system consists of an interconnection of several subsystems, each of which comprises a number of processing units or modules responsible for supporting the main system.
On the other hand, the fact that any brain injury can be selectively altered one of these components also appears to target no other modular organization of brain structure and physiological processes.
Objective of neuroscience in neuropsychological intervention
Thus, the primary goal of neuroscience in this area is to know to what extent the biological functions of the brain are “decomposed” so that this division corresponds directly to the decomposition of processing units which (according to the main postulates of neuropsychology) underpin the performance of a given cognitive function.
In an attempt to achieve the above objective, neuropsychology has attempted to advance in leaps and bounds in the knowledge of the structure and function of the information processing system through study and detailed functional analysis of the behavior of patients with various types of brain damage.
Neurological disorders and disorders
It should be noted that, as the main consequence of brain injury, a pattern of altered and preserved behaviors can be clearly observed in the patient. Interestingly, the altered behaviors, in addition to being dissociated from the rest of the individual behaviors, can be (in many cases) associated with each other.
If an analysis of behavioral dissociations derived from brain lesions is carried out, on the one hand, and an analysis of associations, on the other hand (directing the latter to determine whether all associated symptoms can be explained by virtue of a single component), the components of each modular subsystem could be identified, Within the overall and / or main system, thus facilitating the study of the functioning of each of them.
In the 1980s, some authors identified three different types of behavioral dissociations: classical dissociation, strong dissociation and tendency to dissociation.
When classical dissociation occurs, the individual shows no impairment in performing various tasks, but performs others rather poorly (compared to their executive skills before the head injury).
On the other hand, we speak of strong dissociation when the two compared tasks (performed by the patient for evaluation) turn out to be altered, but the deterioration observed in one is much greater than that observed in the otherIn addition, the results (measurable and observable) of the two tasks can be quantified and the difference between them is expressed. Contrary to the above, we speak of “tendency to dissociation” (it is not possible to observe a significant difference between the executive level of the two tasks in addition to not being able to quantify the results obtained in each of them. and explain differences).
Be aware that the concept of “strong dissociation” is closely related to two independent factors: the (quantifiable) difference between the levels of execution of each of the two tasks, and the extent of executive deterioration presented. The larger the first and the smaller the second, the stronger the dissociation presented.
Traditionally, in our field of study, a set of symptoms (in this case behavioral) that tend to present themselves together to an individual under various conditions has been referred to as a “syndrome”.
Classify patients into “syndromes” it has a number of advantages for the clinical psychologist. One of them is that since a syndrome corresponds to a certain location of the injury produced, it can be determined by observing the patient’s performance in the tasks for his post-assignment to a particular syndrome.
Another advantage for the therapist is that what we call “syndrome” enjoys clinical entity, so that once it is described, the behavior of each patient assigned to it is considered to be described.
It should be noted that in fact, it is rare for a patient under treatment to fit perfectly into the description of a specific syndrome; furthermore, patients with the same syndrome are usually not alike.
The reason is that in the concept of “syndrome” as we know it, there is no restriction on the causes why the symptoms that compose it tend to present together, and these reasons can be at least. three. Type:
There is a single component and / or a modified biological module and all the symptoms presented in the patient’s behavior they derive directly from this alteration.
There are two or more significantly altered components (each of which causes a series of symptoms), but the anatomical structures that keep them functioning and / or support them. they are very close to each otherThus, injuries tend to produce symptoms all together and not one in particular.
3. Chain effect
The direct modification of a neurological element or module resulting from a brain injury, in addition to directly causing a series of symptoms (called “primary symptoms”), changes the executive function of another element and / or neurological structure the anatomical support is originally intact, causing secondary symptoms even without having been the primary target of the lesion produced.