Resumen: La Corteza Cerebral es un dipositivo idóneo para establecer una relación semántica con el mundo. Existen tres diferentes tipos de áreas: 1) los hubs transmodales 2) las zonas de convergencia 3) las zonas unisensoriales. En la actualidad dos modelos de instanciación semántica en la corteza cerebral son los más avanzados. Uno de ellos es el de la Universidad de Berlin. Su autor principal es el Dr Friedemann Pulvermüller. Al igual que el modelo Hub and Spokes, de Cambridge- Manchester- York, utilizan tecnología multivariada para investigar de qué manera la capa de corteza gris cerebral está diseñada en gradientes que actúan como telarañas de absorción de significados.
Semantic processes are related to conceptual management using signs. When asking for brain instantiation some distributed neural networks appears to participate in that processes. Also, the grounded problem means how words are related to perceived objects and executable actions. The embodiment of semantics has evidence of sensorial and motor areas participating in symbolic processes, however, action and perceptual words were founded intact in clinical cases when both unimodal areas were damaged.
In a neuromechanistical proposal, operations were described taking into account that several areas are involved in general meaning processes, others function as convergence zones and there are sensory-motor- emotional embodiments of words grounding. Pulvermüller (2017) considers that there is a wide interconnection between hub candidate areas. The author considers isn’t necessary a unique semantic hub to explain a grounded word, because of large range networks can interact to form a concept. But facts show a special involvement in semantics of determined brain areas. Then, convergent zones are highlighted as multimodal processing areas, differentiating over unimodal ones.
Mechanics of convergent zones to produce semantic is crossed by words- categories, basic mechanisms of semantic grounding are related to words categories. Each convergent zone is more related to a brain structure-dependent word- category (BS-DWC). When instantiation is considered BS-DWC exhibited a categorial hallmark that is cerebral human cortex affine. The later sentence needs to be related to the opacity of human concepts on the contrary direction of naturalistic transparency language theories.
The list of brain categories shows strong visual shaped words, also action, sensorial, abstract and functional ones. Categories arise in between interaction of action- perception and integration amodal areas because semantics require features also relay zones. Hierarchical models have been proposed to explain combinatorial processes. On this way, gradients of activation in a semantic action represent the logic of the semantic instantiation. Then connectivity is fine tunned by indirect connections for word shaping that imply multimodal convergent zones together with unimodal inputs. Categories are gradually instantiated in the cerebral cortex, including cortical- limbic- olfactory regions.
As a first conclusion, the brain cortex appears as a device ideally designed to map the combinatorial properties of semantic. Hebbian processes link neuronal word- linked separated areas. The co-occurrence of activation probabilities of a word is instantiated by the architecture of the brain cortex. The circuits in the left perisylvian language participate in all concepts, increasing its involvement when there is a higher abstraction level. In addition to this area, there are two active zones in the occurrence of learning a word in a context: the lower frontal gyrus and the superior temporal cortex.
But abstraction shows a singular property: Emotional inputs are larger in abstract words compared with more concrete concepts. Also emotionally- abstract words received faster processing vehiculized by the extreme position in the three dimensions that compose emotion charge: Arousal, Valence and Control.
Another kind of abstract concepts is detached of any particular embodiment. Such type of words are weak- related in co-occurrence activation but instantiated in prefrontal, inferior parietal and anterior temporal lobes. The architecture of these three cortex areas exhibits major inside neuronal connectivity and send- receive largely- range connections between the special threes. These areas have a distance to sensory-motor brain areas and limbic circuits.
The question about combinatorial language implies at first if any of concrete- abstract concepts control the other. Results after Magnetic EncephaloGram experiments show the same arising time for the two concepts forms. Abstract concepts that are not emotionally influenced, like ‘rule’ are instantiated by variability mechanisms. High variation forming a concept reveal weak associations but increase activity in the non-unimodal hubs candidates. Grounding of combinatorial semantics when used in context- learning or perception are linked to actions in a mode that need specific research didn’t reach now.