Friday, January 31, 2020
Emotions and the Brain Essay Example for Free
Emotions and the Brain Essay The organization of perceptual systems is identical to that of motility. Perception does not occur through a constructive phase of in-processing that begins in koniocortex. Rather, it develops in the reverse direction over a series of levels to a koniocortical end phase. In other words, the process of object formation unfolds in a cognitive sequence leading from a brainstem preobject through a limbic and generalized neocortical phase, to a final modeling achieved through primary visual cortex. The presumed role of frontal cortex in the elaboration of action structures, that is, the rhythmic or oscillatory components of an action, can explain other seemingly non-motor phenomena which occur with frontal lobe damage. For example, perceptual disorders may arise, not from a primary deficit of perception, but from impairments in the visual exploration of space, including changes in visual search, orientation, and ocular displacement. Two aspects of dynamic systems theory deserve specific mention here; the first is the emergent quality of Jungs methods. Amplification is an intentionally non-linear circumambulation of an image or psychic content; it operates by allowing contextually meaningful associations to be gathered up and enter consciousness. The concept of the limbic system as the focal brain division that must be investigated in order to understand emotionality. The medial surfaces of the telencephalic hemispheres (including cingulate, frontal, and temporal lobe areas especially the amygdala) and interconnections with septal, hypothalamic, and central-medial brain stem areas as part of the neural landscape that constituted the emotional brain. Cortical control of primitive behaviors and basic emotions has been achieved in several ways. One way was for the cortex to extend emotions in time by allowing organisms to dwell on past and future events. The organizational principle that has been most commonly used to summarize the neural infrastructure of emotional processes has been Paul MacLeans concept of the triune brain. According to the classic version which offers a conceptual cartoon of the major layers of neural development, the functional landscape of the brain is organized in three strata of evolutionary progression. Although humans have the largest frontal lobes of any species, dolphins have a massive new brain area, the paralimbic lobe, that we do not possess. The paralimbic lobe is an outgrowth of the cingulate gyrus, which is known to elaborate social communication and social emotions (such as feelings of separation distress and maternal intent) in all other mammals. We should always keep in mind a key conceptual distinction when we consider brain operating systems, namely, how open or closed are these systems in relation to environmental influences FLA loop The neural substrate of language consists of a complex hierarchical system of levels corresponding to stages in neocortical evolution. The system has an anterior (frontal) and posterior (temporo-parieto-occipital) component. The two main classes of aphasia, the non fluent and the fluent aphasias, refer to these components, while the various aphasic syndromes within each class point to different levels within the anterior or posterior sector. The structure as a whole develops out of medial and paraventricular formations through several growth planes of limbic and paralimbic (transitional) cortex to a stage of generalized (association, integration) cortex. The organization of perceptual systems is identical to that of motility. Perception does not occur through a constructive phase of in-processing that begins in koniocortex. Rather, it develops in the reverse direction over a series of levels to a koniocortical end phase. In other words, the process of object formation unfolds in a cognitive sequence leading from a brainstem preobject through a limbic and generalized neocortical phase, to a final modeling achieved through primary visual cortex. In a fashion similar to that of the frontal sector, the perception leads from a global pre-object in a unitary field at a preliminary level to the final more or less contralateral hemifield representation at a koniocortical end stage. (Christianson, 1992) Impaired initiation with lesions of mesial or orbito-frontal cortex may involve the action as a whole, or partially. The patient may be unable to initiate any action (akinetic mutism) or show hypoactivity, inertia and lack of spontaneity. These latter symptoms may represent attenuated forms of akinetic mutism. Perhaps, the degree of encroachment on, or distance from, core regions of frontal limbic cortex (e. g. , anterior cingulate gyrus) determines the extent of hypoactivity. In the partial disorders there is difficulty initiating a vocal act (mutism, transcortical motor aphasia) or limb action (alien hand, SMA syndrome and related disorders). Perseveration also occurs with damage to frontal limbic areas and is related to disturbed initiation. The persistence of a performance is the other side of an inability to go on to the next. Impaired initiation may occur without perseveration, but it is questionable whether the reverse is true. In fact, in perseveration, the initiation deficit often seems primary, for perseveration is greater for tasks which are more difficult, and it tends to involve previously successful performances. (Christianson, 1992) With convexity lesions the action is disrupted at a stage subsequent to its activation. Derailments occur at serial points in the unfolding of the action toward a goal. Apraxia, a substitution or defective selection of partial movements with lesions of left premotor cortex, is due to an alteration of motor timing, or a change in the kinetic pattern for a particular motor sequence. Other frontal disorders may have a similar basis. Agrammatism, dysprosody and expressive amusia probably represent the disruption of an oscillator which elaborates the rhythmic or prosodic contour of an utterance or vocal action. The presumed role of frontal cortex in the elaboration of action structures, that is, the rhythmic or oscillatory components of an action, can explain other seemingly non-motor phenomena which occur with frontal lobe damage. For example, perceptual disorders may arise, not from a primary deficit of perception, but from impairments in the visual exploration of space, including changes in visual search, orientation, and ocular displacement. The lack of drive or motivation in frontal patients can also be approached from a motor standpoint. I have suggested that base levels in the action elaborate the experience, or feeling, of drive and that this experience, like the Innervationsguhl of Wundt, arises as an accompaniment of the action development rather than as an energy or a force which is only an underpinning. In other words, drive undergoes a development together with action. Some actions appear to be motivated by drives or instincts, others are purposeful or goal-oriented, and still others are volitional, in the sense that decisions are made, actions can be delayed and even witheld in pursuit of a goal. My guess is that these feeling states drive, purposefulness, volition correspond with evolutionary levels in the action development, and that this is why damage to the action structure impacts on the feeling state specified by the damaged processing stage. (Lazarus, 1991) Actions also elaborate intentions, the feeling that one it an agent who acts on an environment. This is part of the temporal unfolding of the action and its continual surge toward a future state. It is the basis for our distinction of passive and active movements. This feeling, and the other affects which the action generates, are bound up with the sense of anticipation and forward growth. The loss of, or a change in, this direction toward the future has the consequence of a greater responsiveness to ongoing stimuli and an apparent tendency to live for the immediate present. The loss of this active or volitional relation to the world is, ultimately, the most profound effect of damage to the frontal lobes. The action unfolds into the volumetric space of limbic cognition, a space of dream and hallucination. The action moves outward beyond the body itself to an extrapersonal field of body movement that is still part of and continuous with subjective mental space. This is not a grasping or manipulation space, for objects have not yet exteriorized. The emerging action is read off into keyboards innervating the proximal musculature. Actions leave the body axis and are distributed through the proximal muscles into the space around the body or onto the body itslef. At this stage, the first separation appears between perceiver and object, actor and object acted upon, agent and action. The motor envelope differentiates into partial actions, objects begin to clarify, and space begins to expand, fractionate, and draw away from the perceiver. (Lazarus, 1991) The role of limbic mechanisms in action is brought home even more clearly by conditions in which there is damage to limbic-derived neocortex on the mesial aspect of the frontal lobe. Bilateral damage to the anterior cingulate gyrus gives rise to a state of akinetic mutism resembling that which can occur with damage to the upper brainstem. The patient appears to be in a catatonic stupor and, as in catatonia, there are periodic bouts of excitement that give way to a persistent vegetative state. Stimulation of this region in man produces motor and affective responses suggestive of a primitive or archaic level in behavior. Stimulation adjacent to the anterior cingulate gyrus in the supplementary motor area (SMA) causes iteration or arrest of vocalization and proximal movement, especially of the upper limbs. With damage there may be a release of automatisms and primitive synergies of the arm and hand (alien hand) or difficulty initiating action with the arm though strength and coordination are intact. There may also be difficulty initiating speech. This can lead to selective mutism or selective akinesia, that is, ambulatory mutism or good speech with imparied initiation of limb movement. Selective difficulty initiating movements with the lower extremities occurs in the so-called gait apraxia, or magnetic gait, often associated with hydrocephalus. (Wilson, 1983) In the microgenetic theory the SMA mediates preparatory stages in action generation prior to conscious awareness. Lesions of this area disrupt speech, limb, and body action in a common manner early in the processing of the action, prior to the specification of constituent movement patterns. The disturbance of speech was viewed as motoric, not linguistic or propositional. In the microgenetic view, each response represents a bundle of action structures, consisting of the series of stages through which the action develops. Pathology disrupts the action at different points in this process. The site of the lesion determines the point in the sequence that is disrupted, and this point or processing stage constitutes the symptom or abnormal behavior. Microgeny maps onto patterns of phyletic growth. The structure of an action and the symptoms that correspond to levels in this structure are distributed over stages in forebrain evolution. Damage to older orbital and mesial frontal limbic formations leads to impaired activation (response bias or perseveration and lack of initiation), damage along the convexity leads to derailment of the action after adequate initiation (distractibility, apraxia, and confabulation), and damage to premotor and motor cortices leads to a defect in implementation of distal targets (misarticulation, clumsiness, and weakness). Specifically, the evolutionary progression from limbic to motor cortices retraces the sequence of processing stages in the microtemporal elaboration of an action. Seizures involving mesial frontal limbic cortex can lead to stereotypical actions of a purposeful type, such as scratching ones head, manipulating imaginary objects, or pacing. The alien hand syndrome also represents a type of released automatism. Here a more complex integrated behavior of a purposeful but not volitional type is associated with damage or stimulation to zones intermediate in the action microgeny. The inner relationship between (impaired) initiation and (released) automatism recurs but now in the context of a more differentiated action pattern, involving segmental or vocal movements. Non-Linear Dynamic Systems. Two aspects of dynamic systems theory deserve specific mention here; the first is the emergent quality of Jungs methods. Amplification is an intentionally non-linear circumambulation of an image or psychic content; it operates by allowing contextually meaningful associations to be gathered up and enter consciousness. As the limit of personal associations is reached, if further analysis is required, the net is widened to include cultural and archetypal elements. For this expansion to remain clinically relevant it must offer an experiential dimension as well as being an intellectual event; affective involvement is crucial, as will be discussed with dream work. A precondition for entering a state of (analytic) consciousness that can facilitate a mutative employment of transpersonal material was noted by Jung and more fully discussed by Bion, the suspension of ordinary knowing this link between Jung and Bion was delineated by Fordham along with a number of other areas of overlap between them. All psychoanalysts looking at the applications of infant research to adult analysis, subscribe to variants of an emergentist paradigm grounded in non-linear dynamic systems. Sanders ideas about paradox and polarity are resonant with Jungs core perception of the dissociability of the psyche that leads to his theory of complexes with the consequent aim in analysis to foster synthesis and integration via the transcendent function. Every living system must cope with uncertainty that places it in a state somewhere between continuity and change, core polarities for Sander. In the therapeutic setting, fluctuations in relational certitude and doubt provide an emergent edge through which the co-constructed third of the relationship becomes the locus of the transcendent function. The system radically expands our understanding of transference and points to the creative possibilities inherent in a ââ¬Å"newâ⬠experience. Which complexes are constellated in the analyst, in the patient and between them at such moments should likely be considered.
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