IMPULSIVITY. — In common language, it denotes the tendency to perform, under the pressure of a conscious or subconscious ideational-affective psychic state, sudden acts characterized by irrationality, inappropriateness, suddenness, and irresistibility.
Normally, the act of intellectual appetition, framed within the plan of a purposeful representation, is sustained and expressed under the impetus of a motive, a psychological complex consisting of an idea more or less charged with affective tension. Thus, the characteristics of the act of will are shaped by those of the animating motive, whether logical or illogical, legitimate or illegitimate, proportionate or disproportionate. Hence, the impulsive act, whose determination is tied to the sudden emergence in the subject’s mind of a motive—often tyrannically obsessive and charged with affective tension—does not arise logically from a well-ordered series of reasonable premises but discharges itself tumultuously and disorderly through the psycho-physiological moment ("impulse") into the practical act.
Two circumstances contribute to impulsivity: one psychological, represented by the permanent or temporary emptiness of consciousness, poor or devoid of inhibitory counter-motives, whereby the motive-idea tends automatically to transform itself into an act; the other of a physiological nature, whereby operative impulses tend to overflow from their delimited channels of conduction, unleashing, as it were, an internal short circuit—a storm of emotional and motor reactions foreign or disproportionate to the desired responses dictated by the particular circumstances of the moment. Impulsivity can manifest in varying degrees, from the mildest, in which the voluntary act loses to a greater or lesser extent its characteristics of deliberation and logical motivation, to the most severe, where it assumes the aspect of an instinctive, immediate, violent reaction in which the intellectual element seems entirely absent, wholly absorbed by the violent discharge of emotion and motor activity. Some authors (G. H. Schneider) wish to establish close relationships, even to the point of identity, between impulse and instinct, speaking of instinctive impulses that group into "impulses-sensations," "impulses-perceptions," and "impulses-ideas."
Particularly severe manifestations of impulsivity are observed in epilepsy (v.), both in its overt forms of convulsive seizures and in its masked aspects of "equivalents" or sudden impulses to commit acts of violence, to set fires (pyromania), or to destroy (clastomania); in the disposition of chronic alcoholism (v.); in manic episodes and in the *raptus melancholicus* of manic-depressive psychosis, which may culminate in the sudden suicide of the afflicted; and in many other forms of chronic intoxication or psychosis, such as cocainism (v.), various forms of dementia (v.), paranoia (v.), and feeblemindedness, among others. Thus arises the medico-legal figure of the impulsive madman, capable of the most heinous and sudden crimes, characterized by the absence of utilitarian motivation, the incomprehension and indifference toward the harm inflicted, and the lack of remorse.
Impulses of psychopaths must be distinguished from those of obsessive psychosis (v.), in which the individual has the sudden idea of performing an action that is disagreeable to him or in contrast with the intellectual or moral framework of his personality. The subject feels that he will not be able to resist the obsessive impulse tormenting him, which is so painfully experienced by his conscience (and it is precisely in this intellectual opposition and moral suffering that the specific difference from the impulses of the mentally ill lies). If the action prompted by the obsessive impulse is of little importance, harmless, and devoid of moral consequence, the individual eventually performs it, thereby regaining, at least momentarily, his peace of mind; if the idea involves a repugnant, seriously harmful, or sinful action, it is inhibited and repressed, though the suffering of the struggle and the fear of a possible future defeat remain.
Impulsivity always represents a flaw in the normal unfolding of volitional activity and, correspondingly, in the imputability of the act performed. It is not possible to provide a general criterion for judgment here, as it is tied to the characteristics of the illness producing the defect, ranging from cases of full irresponsibility to those of modest mitigation. For this reason, reference is made to the individual entries dealing with the various chronic intoxications and psychoses capable of influencing the psycho-motor activity of the individual; see also PASSIONS.
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