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Self Comes to Mind

Self Comes to Mind

Titel: Self Comes to Mind Kostenlos Bücher Online Lesen
Autoren: Antonio Damasio
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and changes in the protoself begin to occur. These steps take place in close temporal proximity, in the form of a narrative sequence imposed by real-time occurrences. The first level of connection between modified protoself and object would emerge naturally out of the time sequence with which the respective images are generated and incorporated into the cortege of the mind. In brief, the protoself needs to be open for business—awake enough to produce the primordial feeling of existence born out of its dialogue with the body. Then the processing of the object has to modify the varied aspects of the protoself, and these events have to be connected to each other.
    Might there be a need for neural coordinating devices to create the coherent narrative that defines the protoself? The answer depends on how complex the scene is and whether it involves multiple objects. When it does involve multiple objects, and even if the complexity is nowhere near the level that we shall consider in the next chapter regarding the autobiographical self, I believe we do need coordinating devices to achieve coherence. There are good candidates for that role, located at the subcortical level.
    The first candidate is the superior colliculus. Its candidacy will evoke smiles, even if the coordinating credentials of this tried-and-true device cannot be questioned. For reasons outlined in Chapter 3 , the deep layers of the superior colliculi are suited to this role. By offering the possibility of making superpositions of images of different aspects of the internal and external worlds, the deep layers of the colliculi are a model of what the mind-making and self-making brain eventually became. 10 The limitations are obvious, however. We cannot expect the colliculi to be the lead coordinator of cortical images when it comes to the complexity of the autobiographical self.
    The second candidate for the role of coordinator is the thalamus, specifically the associative nuclei of the thalamus, whose situation is ideal to establish functional linkages among separate sets of cortical activity.
Touring the Brain as It Constructs a Conscious Mind
     
    Imagine the following setting: I am watching pelicans feed breakfast to their young. They fly gracefully over the ocean, sometimes barely above the surface, sometimes higher up. When they spot a fish, they suddenly plunge toward the ocean surface, their Concorde-like beaks in landing attitude, their wings pulled back in a beautiful delta shape. They disappear into the water to emerge a second later, triumphant, with a fish.
    My eyes are busy following the pelicans; as the pelicans move about, nearer or farther away, the lenses in my eyes modify their focal distance, the pupils adjust to the varying light, and the eye muscles work briskly to follow the birds’ swift movements; my neck helps with appropriate adjustments, and my curiosity and interest are positively rewarded by observing such a remarkable ritual; I am enjoying the show.
    As a result of all this real-life bustle and brain bustle, signals are arriving in my visual cortices, fresh from retinal maps that plot the pelicans and define their appearance as the object-to-be-known. A profusion of moving images is being made. On parallel tracks, signals are also being processed in a variety of brain regions: in the frontal eye fields (area 8, which is concerned with eye movements but not with visual images per se); in the lateral somatosensory cortices (which plot the muscular activity of the head, neck, and face); in emotion-related structures in the brain stem, the basal forebrain, the basal ganglia, and the insular cortices (whose combined activities help generate my pleasant feelings about the scene); in the superior colliculi (whose maps are receiving information about the visual scene, eye movements, and state of the body); and in associative nuclei of the thalamus engaged by all the signal traffic in the cortex and brain-stem regions.
    And what is the upshot of all these changes? The maps that plot the state of sensory portals and the maps that pertain to the interior state of the organism are registering a perturbation. A modification of the protoself’s primordial feeling now becomes differential feelings of knowing relative to the engaging objects. As a result, the recent visual maps of the object-to-be-known (the feeding pelican flock) are made more salient than other material being processed nonconsciously in my mind. That other material might

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