Protective Shield
PROTECTIVE SHIELD
In Freud's psychophysiological model, the term protective shield designates an essential function of the psychic apparatus and the mechanism responsible for it. This function is to protect the organism from potentially harmful excitations coming from the outside world. The protective-shield function, in the context of the theory of the ego, is the result of a complex, dynamic barrier between outside and inside—a barrier in which the protective shield is posited as the most superficial and inert element.
As early as 1895, in "Project for a Scientific Psychology," (1950c [1895]), Freud hypothesized the existence of a mechanism responsible for protecting the "phi neurons" from an excessive influx of exogenous stimuli. In the psychic apparatus, governed by the principle of constancy (elevated quantities produce unpleasure), the sudden irruption of large quantities causes pain. Thus the phi neurons, which receive stimuli perceptions from the external world, must allow only small "quotients" or quantities to pass, but at this point Freud did not specify how this shield quantity ("Q-screens") functioned.
From 1920 to 1926, granting the perceptual apparatus its full importance in relations between the ego and the outside world, Freud hypothesized as an adjunct to the Preconscious-Conscious system the protective shield, which constitutes its most superficial layer. This system is operative only with regard to excitations coming from the outside world, and its function overrides that of the layer that receives excitations. By contrast, excessive energies that come from within are received directly by the Preconscious-Conscious system, which projects them to the outside so that the protective shield can be used against them.
In Beyond the Pleasure Principle (1920g), in order to understand the phenomenon of painful repetition in traumatic events, Freud posited in human beings the equivalent of the cortical layer that receives stimuli in living cells. Owing to the constant impact of excitations, the substances of the Preconscious-Conscious system and its protective shield undergo a profound modification. To a certain extent, the substance of the protective shield abandons the structure characteristic of living entities and becomes a special membrane that usually keeps exogenous stimuli separate. This inert filter is combined with two other elements to finally make up a true dynamic barrier between outside and inside. In the first place, the sensory organs, which periodically filter out sufficient amounts of the excitations coming from the outside world, constitute another protective shield (a hypothesis taken up again in "A Note upon the 'Mystic Writing Pad,"' [1925]); and finally, there is preparatory anxiety, which is the most dynamic element of the protective-shield system. This line of defense, prepared by a hyper-cathexis to receive and bind the sums of excitation flowing in from the exterior, shields against breakthrough and trauma (a hypothesis confirmed in Inhibitions, Symptoms and Anxiety, [1926]). Here, on either side of the barrier that prevents the development of anxiety, consisting of the Preconscious-Conscious system and its protective shield, Freud differentiated between two types of anxiety: on one side, the automatic anxiety of the states of the immature ego, which corresponds to an uncontrolled energy and is closely connected with trauma; and on the other, signal anxiety, which depends on a strongly hierarchical mechanism of the ego, which warns it in cases of real, external danger or internal, pulsional danger and allows the ego to mobilize its defenses.
After Freud, the protective-shield function of external objects was emphasized in the work of Donald W. Winnicott and Wilfred R. Bion. In Winnicott's view (1958), the environment, and especially the mother, must present the external world to the infant in a way that preserves the illusion without which the child's encounter with the world would be traumatic. In Bion's view (1962), the mother's capacity for reverie plays a foundational role in the infant's thought processes.
In Le Penser: Du Moi-peau au Moi-pensant (1994), Didier Anzieu held that the Skin-ego and the Thinking-ego both fulfill the protective-shield function, each at its own level. The Skin-ego defends the psyche against endogenous pulsional breakthroughs and simultaneously contributes to satisfying the appetite for stimulation; the Thinking-ego protects the Reality-ego from being flooded by thoughts and at the same time ensures that there is continuity in thinking activity. Lastly, Claude Smadja and Gérard Szwec attributed a protective-shield function to the death drive and self-calming behaviors by way of the repeated actions of weak discharges that involve motricity and perception; this is particularly applicable in the case of psychosomatic structures.
Ultimately, since the aim of the psychic apparatus is control over excitations, it can be said that under normal conditions, all mental work fulfills the protective-shield function.
Josiane Chambrier
See also: Beyond the Pleasure Principle ; Censoring the lover in her; Conscious processes; Excitation; Hyper-cathexis; Infant observation (therapeutic); Maternal; Projection; Protective shield, breaking through the; Pre-conscious, the; Psychic envelope; Skin-ego.
Bibliography
Anzieu, Didier. (1994). Le Penser. Du Moi-peau au Moi-pensant. Paris: Dunod.
Bion, Wilfred R. (1962). Learning from experience. London: Heinemann.
Smadja, Claude. (1993). A propos des procédés autocalmants du Moi. Revue française de psychosomatique, 4, 9-26.
Szwec, Gérard. (1993). Les procédés autocalmants par la recherche répétitive de l'excitation. Les galériens volontaires. Revue française de psychosomatique, 4 27-51.
Winnicott, Donald W. (1958). Collected papers. Through pediatrics to psychoanalysis. New York: Basic Books.