Raymond E. Fancher

York University

In all his psychoanalytic works published during his lifetime, Sigmund Freud presented his theory in completely psychological terms. He explicitly disclaimed any intention of correlating his concepts with underlying neurological processes. "Every attempt . . . to discover a localization of mental processes, every endeavour to think of ideas as stored up in nerve cells, and of excitation as travelling along nerve-fibres, has miscarried completely," he wrote in 1915. "Our psychical topography has for the present nothing to do with anatomy; it has reference not to anatomical localities, but to regions in the mental apparatus, wherever they may be situated in the body" (Freud, 1957/1915, pp. 174-175, emphasis in original).

While Freud's statement is correct as far as it goes, it is also misleading. It is true that psychoanalytic theory can be understood, and psychoanalytic psychotherapy practiced, without resorting to neurological concepts. But the statement masks the fact that many important psychoanalytic hypotheses, especially those concerning the characteristics of unconscious mental processes, originated in a context of unpublished neurological speculation, and were only later freed of their neurological trappings.

Freud, after all, had been formally trained in neurophysiology and neuropathology. As a young man he made important if unrevolutionary contributions to both those fields, including well-received monographs on aphasia and infantile cerebral palsies. It was not until the late 1880s, as Freud entered his mid-thirties, that his attention was increasingly drawn to the psychological problems posed by neurotic conditicns, especially hysteria. As his psychological knowledge grew, Freud quite naturally tried to integrate it with his neurology. In 1895, immediately after completion of his classic psychological chapters for Studies on Hysteria, Freud became intensely preoccupied with what he called a "Psychology for Neurologists," an integrating theoretical work whose goal was "to see how the theory of mental functioning takes place if quantitative considerations, a sort of economics of nerve force, are introduced into it" (Freud, 1954, pp. 119-120).

The result of Freud's labor was an untitled handwritten manuscript, one hundred pages in length, which he mailed to his Berlin friend and confidant, Wilhelm Fliess. Though Freud continued to correspond with Fliess about the work for two years, he never edited it for publication. The manuscript disappeared from view for many years, remaining completely unknown to most Freud scholars until eleven years after his death. Then, in 1950, it was published in its original German as part of a collection of Freud's correspondence with Fliess. When the English edition appeared in 1954, the translators provided it with the title Project for a Scientific Psychology (Freud, 1954/1895, pp. 355-445; quotations in this paper will be taken from the later translation published in 1966).

It is not easy to read the Project, partly because it was never edited for publication, and partly because of the inherent complexity and ambiguity of some of its subject matter. Nevertheless, it is of the greatest interest to anyone who wants to understand how Freud's theories actually developed. Occurring at the transition point between his neurological and psychoanalytical careers, the Project's speculations were seminal for Freud. Among the topics to receive their first systematic treatment there were the dichotomy between an unconscious "primary process" and a conscious "secondary process" mode of thought; the formulation of an "ego" as the directive, reality-attuned agency in the psyche; and the theory of dreams. As James Strachey, Freud's English editor and translator has remarked: "The Project, or rather its invisible ghost, haunts the whole series of Freud's theoretical writings to the very end" (Strachey, 1966, p. 290).

Background of the Project

Two of Freud's teachers were especially influential in providing the neurological background he brought to the Project. First was Ernst Brücke (1810-1892), an eminent physiologist whom Freud once described as the person "who carried more weight with me than anyone else in my whole life." As a friend and admirer of Hermann Helmholtz, Brücke carried an attitide of thoroughgoing mechanism into all of his physiological work, an attitude clearly expressed by a remarkable declaration he had made as a young man: "No other forces than the common physical-chemical ones are active within the organism. In those cases which cannot at the time be explained by these forces one has either to find the specific way or form of their action by means of the physical mathematical method or to assume new forces equal in dignity to the physical-chemical forces inherent in matter, reducible to the force of attraction and repulsion" (quoted in Bernfeld, 1949, p. 171). According to Brücke's teaching the entire organism, including its neurological and psychological aspects, was to be understood as a machine - vastly complicated, perhaps, but operating according to perfectly comprehensible physical principles.

Brücke encouraged speculation in neurophysiological work, so long as it remained within the-mechanistic framework and did not actively violate any known physiological principles. In his own work, for example, he hypothesized the existence of an as yet undiscovered mechanism in the nervous system whose function is to "summate" excitation. Such a mechanism could account for the observation that a constant low level stimulus impinging on a receptor (e.g., a morsel of food lodged against the esophagus) elicits reflexive responses (swallowing) only periodically. Brücke suggested that the excitation from the stimulus enters the nervous system via a receptor, and then accumulates in a nervous center until a certain threshold is reached. Only then does the center initiate the reflex by discharging its accumulated excitation into the motor nerves. No one had ever seen such an accumulating mechanism in an actual nervous system, but it was at least plausible within the general mechanist view, and not inconsistent with known facts about the nervaus system. In the Project, Freud adopted both this specific conception of the neurological "summation of stimuli" and Brücke's general strategy of mechanistic neurological speculation.

The second of Freud's teachers with a major direct influence on the Project was Theodor Meynert (1833-1892), a celebrated brain anatomist who used his anatomical knowledge as the starting point for a speculative model of the mind. According to this model the cortex is the anatomical substrate of mind, with specific cells in the sensory and motor areas representing specific ideas and memories. The specific cells are potentially interconnected in a vast network by means of "association fibres," the bulk of whose substance lies in the frontal lobes. After two cells have been simultaneously excited (equivalent to the simultaneous arousal or two ideas), an association fibre opens up between them. With each subsequent simultaneou excitation, it opens up further. This provides the anatomical basis for the association of ideas; after an association fibre has opened up it provides a pathway by which excitation in one center can flow directly to the other. A "train of thought" is simply the consequence of excitation flowing through a series of cortical cells that have been associated because of previous simultaneous excitations.

Every person, of course, has a unique pattern of experience and so develops a unique pattern of cortical associations that represent his memories. These associations are the anatomical substrate of a person's "individuality," and Meynert referred to them collectively as the ego (German Ich).

If the ego has not had time to develop, as in an infant, thought processes tend to be random or determined largely by any pattern of stimulation that happens to be impinging at a given moment. William James, an admirer of Meynert, famously described the mental life of an infant as "one big blooming buzzing confusion" - an accurate description from the point of view of Meynert's theory. Meynert also believed that the associations of an adult ego could be temporarily or permanently weakened, with a similar result of random or confused thought processes. The state of sleep brings on a temporary ego weakness, for example, with the consequent bizarre mentation that characterizes dreams. Toxic conditions in the brain can produce a more permanent ego weakness, resulting in psychotic states.

Though Meynert's model was plausible from the prevailing neurological point of view, its major fault was the simplistic psychology it assumed. AI1 of the directive influences on thought it postulates are derivable from past pairings of stimuli, a limitation that prevents it from adequately accounting for the motivated nature of most thought processes. Previous associations certainly play a role, but they do not tell the whole story. Consider the simple example of a person who is asked to give the first though that comes to mind in response to the stimulus word "ear." Under normal onditions the person might respond with the word "eye," a concept that has been frequently associated with "ear" in the past. If the person is very hungry, however, with thoughts turning naturally toward food, he or she might well respond with a more remote but food-related associate such as "corn" (as in an ear of corn). Variable motivational influences like this on the train of thought were not sufficiently explained by Meynert's model. Though Freud adopted much of Meynert's point of view in the Project, he attempted to remedy this deficiency.

The particular psychological problems Freud wished to account for in the Project - including the motivated nature of thought - arose largely from the investigations of hysteria that he and Josef Breuer had described in Studies on Hysteria (Breuer and Freud, 1955/1895). The essence of their theory was that hysterical symptoms result when emotion-laden memories do not have normal access to conscious recollection. The emotional energy associated with these memories cannot be expressed and "catharted" in the normal way, but instead becomes "strangulated" and builds up in pressure within the nervous system. Eventually the pressure becomes so great that it cannot be contained, so the energy discharges into the motor nerves. The result is a physical manifestation that has the earmarks of a symptom - a contracture, paralysis, tremor, etc. - but that is not caused by underlying organic pathology. These "conversions" of emotional into physical energy were the hallmark of hysteria. The therapy Freud and Breuer developed employed hypnosis or free associational techniques to restore the unconscious "pathogenic ideas" to conscious accessibility. Once entertained in consciousness, their emotional energy could be expressed normally and the symptoms removed.

In the course of his investigations Freud discovered some further peculiarities of hysterical symptoms. Often, for example, individual symptoms seemed caused by several pathogenic ideas at the same time, and bore a symbolic relationship to each of them. Thus one patient's hand tremor was found to be caused by three separate traumatic memories: a slap on the hand she had once received as a punishment in childhood, a bad fright she had once received while playing the piano, and a back massage that she had been forced to administer to a detested relative. These memories were alike only in that they all involved her hands - which thus served as a convenient symbol for all three at once. The hand tremor did not disappear completely until all three ideas had been brought to consciousness. In Freud's terminology, the symptom was overdetermined by these three pathogenic ideas at once.

In the course of helping his patients bring their pathogenic ideas to consciousness Freud came forcibly to grips with the motivated nature of thought. As the ideas were on the verge of coming to awareness, the patients frequently exhibited so much anxiety and distress that Freud could only conclude that they actively but unconsciously resisted those thoughts. It was as if the patient had unconsciously made a decision that it was better to experience the symptom than to think the thought. The symptom then could be thought of as a defense against an intolerable thought; on occasions when the associative process should normally have brought the thought to mind, the symptom appeared as a more acceptable substitute. Clearly the associational process was influenced not only by previous pairings of stimuli, but also by motivational factors that caused patients' consciousness to veer away from some ideas, and towards others as more acceptable substitutes

Thus when Freud set out to construct his "Psychology for Neurologists" in 1895, he had the theories, assumptions, and points of view of his mentors to use as starting points. He had to modify and elaborate their ideas, however, so as to account for the phenomena of hysteria. His hypothetical nervous system had to be capable of discharging accumulated emotional energy into the musculature, thus creating hysterical conversion symptoms. It also had to create overdetermined and symbolic relationships between symptoms and unconscious ideas. And it had to modify associational predispositions built up in the past with motivational factors acting in the present.

Freud's model, as described in the Project, was only partially successful. Its most notable failure was an inability to provide a plausible mechanical explanation for the phenomena of psychological defense. Nevertheless, the work laid the groundwork for virtually all of Freud's later theorizing about the basic structure and function of the human mind.

Neurological Assumptions of the Project

At the very outset of the Project, Freud makes clear his intention to follow the mechanistic principles he had learned from Brücke: "The intention is to furnish a psychology that shall be a natural science: that is, to represent psychical processes as quantitatively determinate stages of specifiable material particles" (Freud, 1966, p. 295). The material particles constituting the basic units of Freud's system are neurons (the neuron theory had first been enunciated by Waldeyer just four years before the Project was written), and the quantitatively varying factor is an unspecified form of energy that Freud simply calls "Q". Neurons are conceptualized as receptacles that can be filled up, or cathected by varying amounts of Q.

Following Meynert, though employing somewhat different terminology, Freud assumes that certain cortical neurons are the anatomical equivalents of ideas and memories. He calls these neurons, collectively, the Psi system. Cathexis of a Psi neuron by Q is equivalent to the excitation of the idea it represents, and such excitation may occur to varying degrees, depending on the extent of the cathexis. Cathexis does not cause the idea to come into consciousness, however. The principal effect of Psi cathexes is to organize neuro-psychological processes according to principles that will be described later; only under certain conditions - also to be described later - do they result directly in consciousness.

The Psi neurons make up a vast, interconnected network, with "contact barriers" separating them from each other. Still following Meynert, Freud suggests that the resistance of a contact barrier becomes reduced after the neurons on either side of it have been simultaneously cathected. In Freud's terminology, such neurons have become "facilitated" with respect to each other, so on future occasions Q can flow from one to the other. Facilitations are directly analogous to Meynert's associations, and constitute the physical substrate of memory.

The Project goes beyond Meynert, however, when it postulates a second factor besides facilitations in the determination of the paths Q must follow in Psi. Simultaneously cathected neurons will not only become predisposed to exchange Q in the future, but also in the present. Freud describes the hypothetical neuronal process involved as follows:

It follows in terms of our theory that [a quotient of Q] passes more easily from a neurone to a cathected neurone than to an uncathected one ... Cathexis is here shown to be equivalent, as regards the passage of Q, to facilitation. Here, therefore, we become acquainted with a second important factor in directing the course taken by the passage of Q. A [quotient of Q] in neurone a will go not only in the direction of the barrier which is best facilitated, but also in the direction of the barrier which is cathected from the further side. The two factors may support each other or may in some cases operate against each other (Freud, 1966, p. 319).

Here is at least a partial solution to the problem of accounting for motivated thought. A motive state results in the cathexis of certain neurons whose "ideas" are associated with the need. According to Freud's second principle, these cathected neurons will now tend to attract still more quotients of Q to themselves, from other simultaneously cathected neurons. Psychologically, this means that the ideas that are cathected because of the motive state tend to involve themselves in all ongoing thought processes, quite independently of their previous associational histories. Figure 1 illustrates this process for the example described earlier of the associations to the word "ear" under hungry and non-hungry condition.

A. "Ear" has been more strongly facilitated with "eye" than with "corn" because of past associations. Thus there is less resistance between "ear" and "eye" than between "ear" and "corn" - as represented by the single and double lines. Under normal conditions Q flows more easily from "ear" to "eye" than to "corn."

B. The person becomes hungry, as represented by the cathexis of a "hunger" neuron. Because of prior facilitations, "hunger" can easily transmit some of its Q to "corn," which in turn becomes partially cathected.

C. Because of its partial cathexis, "corn" now can attract still more Q to itself. As a result of this temporary factor, Q may now flow from "ear" to "corn" even more easily than to the normally better facilitated "eye."

Figure 1: The influence of simultaneous cathexis and the motivated nature of thought


The totality of the facilitations and the cathexes in Psi constitute the ego, the organization that determines the flow of Psi cathexes. Freud's ego concept is thus more complex than Meynert's, including the constantly varying overall pattern of cathexes in the neurons, as well as the permanent facilitations that have been laid down by past experience. As Freud describes it, ". . . the ego is to be defined as the totality of the Psi cathexes, at the given time, in which a permanent component is distinguished from a changing one. It is easy to see that the facilitations between Psi neurones are a part of the ego's possessions" (Freud, 1966, p.323).

Another of Freud's fundamental neurological hypotheses derives from Brücke's "summation of stimuli" concept. Freud assumes that every Psi neuron has a certain threshold for discharge. As long as its cathexis remains below this threshold, all of its Q remains confined to the Psi system; i.e., it may exchange small quotients of Q with other Psi neurons according to the principles just described. When the neuron becomes "hypercathected," however, so that its Q surpasses the threshold, it discharges its accumulated Q completely out of Psi in a single burst. In the waking state the path of discharge is to a motor nerve, which in turn initiates a particular muscular movement. Generally, the particular movement bears a clear relationship to the "idea" represented by the discharging Psi neuron. Discharges from the neurons representing "food," for example, result in movements like sucking or chewing. Discharge is the mechanism by which neurological events in Psi can initiate and control overt behavior.

Sources of Energy for Psi

In order to initiate and control behavior, of course, the Psi system must have Q at its disposal to initiate its discharges. Thus an important question concerns the original sources of the Q in Psi. Freud asserts that all Q enters Psi from two different kinds of sources: exogenous sources, which impinge directly upon the sense receptors of the body; and endogenous sources, which are created by the various tissue needs within the body itself. The Q in Psi is a form of energy that has been created (strictly according to the law of conservation of energy) out of the energy constantly impinging on the nervous system both from within and without the body.

While exogenous and endogenous sources are alike in the kind of Q they produce in Psi, they differ greatly in the kind of practical demands they represent for the organism as a whole. When exogenous sources become very intense, they constitute a potentially dangerous external stimulus that must be avoided. In principle, the nervous system provides a straightforward way of accomplishing this by simple responses of flight. Reflexes are the simplest examples of these responses. Painful pressure on the foot, for example, results in the rapid hypercathexis of neurons which discharge and cause a reflexive withdrawal of the foot. Potentially, at least, any external stimulus provides the Q that can initiate a response enabling the organism to flee from or avoid that stimulus.

Endogenous stimulation presents a different and more complicated problem, because it cannot be run away from or avoided by simple or invariable responses. Termination of hunger pangs requires the ingestion of food, for example, and there is no simple or invariable response that will always produce food. Instead, a hungry person must flexibly manipulate the environment, depending on the particular current circumstances. The burden on the nervous system, which must initiate these flexible responses, is accordingly much greater in dealing with endogenous than with exogenous sources of Q. The response of the nervous system, or mind, to this endogenous challenge became a major preoccupation both of the Project and all of Freud's subsequent theoretical works. One of the main pillars of psychoanalysis would always remain an emphasis on the "instincts" or "instinctual drives," which were seen as posing much more profound challenges to the psyche than the straightforward demands from external relaity.

The Development of Wishes

An infant, obviously, is unequipped to deal satisfactorily with its inner needs. Endogenously originating Q rapidly hypercathects Psi neurons, and since there is no specific satisfying response associated with their discharge, the result is a general activation of the musculature. The hungry infant kicks, screams, flails, and indicates its arousal by a general activation. Although this distress response is not adaptive in itself, it sets a chain of events in motion that gradually leads to psychological maturation. The overt signs of distress usually elicit the attention of a mothering figure, who appears and rapidly tends to the infant's needs. This means that a whole series of neurons have bcome cathected either simultaneously or in rapid succession. "Hunger" becomes cathected, soon followed by the external stimuli that cathect "mother," "breast," "food," "satisfaction," etc. After this sequence has been repeated a number of times, strong facilitations develop among all of these neurons. Now, when hunger occurs, Q flows not only to "hunger," but spreads to the other neurons in the facilitated complex as well.

A comparable sequence of development occurs for all recurrent endogenous needs. On a psychological level this translates into a general principle: any recurrent endogenous need comes automatically to arouse wishes for the objects and situations that have been associated with its past satisfaction. Such wishful cathexes provide an important first step toward the infant's capacity to meet its endogenous needs independently, because they provide indications of what must be sought in the external world to meet the needs. As has been shown, such cathected neurons can exert a motivational influence on Psi processes by involving themselves in many associations with other, concurrently cathected neurons. Adaptive, goal-directed thought develops out of the constant interplay between these ideas of what is desired and ideas of what is actually present.

Wishful cathexes pose a danger along with their benefits, however, arising from the possibility of their surpassing the threshold for discharge. The muscular activation following wishful hypercathexis is identical to that produced when the same neurons become hypercathected from exogenous sources. These movements enable the organism to consummate its satisfaction if the required objects are actually present; as has been noted, discharge of the "food" neurons initiates activities such as sucking and chewing. These activities, of course, are appropriate and necessary only if food is actually present; that is, if at least some of the Q cathecting the "food" neurons comes from real food impinging on the sensory receptors. When these same neurons become hypercathected entirely from endogenous sources, however, the responses are inappropriate. Wishes have been mistaken for reality. As Freud put it, "I do not doubt that in the first instance this wishful activation will produce the same thing as a perception - namely a hallucination" (1966, p. 319, emphasis in original).

Such hallucinatory satisfactions might possess many subjective qualities in common with real satisfactions,enabling them to be temporarily mistaken for real experiences. Their satisfaction is short-lived, however, because they do not meet the tissue needs of the body and shut off the flow of endogenous Q. Furthermore, the occurrence of wishful activation may be maladaptive because it inhibits the performance of the effective manipulations that are required to satisfy the wish in reality.

The nervous system's task in adapting to its often conflicting endogenous and exogenous requirements is thus twofold. First it must somehow moderate the intensity of wishful cathexes, keeping them strong enough that they exert a directive influence on the course of thought, but low enough that they do not discharge inappropriately. Second, it must somehow discriminate "real" stimulation from that which is merely imagined. Only when "indications of reality" are present as well as wishful cathexes, should discharges be permitted to occur and activate consummatory responses.

Consciousness and the Omega System

To meet this second function Freud postulates a system of neurons separate from Psi, called the Omega system, that responds to the quality rather than the quantity of impinging stimulation. The neurons of Omega respond to something Freud calls period, constituted by the temporal features of stimulation such as the frequency of its vibration. The psychological results of stimulation of Omega are conscious sensations of quality, with the specific conscious sensations depending on the specific nerve energies of the neurons involved. Although Freud does not explicitly say so, the Omega system corresponds anatomically to the various sensory regions of the brain (e.g., the visual, auditory and other localized sensory centers that had only recently been discovered). Stimulation of Omega is the only cause and source of consciousness in Freud's model.

Omega provides a means of distinguishing wishes from reality because it is stimulated by means of the external sensory receptors. Thus exogenous stimulation which impinges on the receptors results in the cathexis of Omega as well as Psi, whereas endogenous excitation cathects Psi alone. Psychologically, external stimulation excites consciousness, whereas endogenous pressures do not.

Psi processes themselves, like endogenous Q inputs, are devoid of conscious quality. The only way they can call attention to themselves is retrospectively, by means of their discharges. When the discharges activate the musculature, the movements themselves excite proprioceptive sensory receptors, and thus Omega. Even private thought, so long as it is conscious, is the result of low level muscular activation: "As is will known, indeed, what is called conscious thought takes place to the accompaniment of slight motor expenditure" (Freud, 1966, p. 367). A conscious train of thought, then, is nothing more than a succession of discharging neurons. Psi cathexes that do not surpass the threshold for discharge do not excite consciousness, even though they may exert an important organizing influence on Psi activity and discharge in other neurons. Here is a rationale for the well-known psychoanalytic assertion that conscious mental experience is but the tip of the iceberg.

Role of the Ego

While the Omega system's ability to detect and discriminate exogenous stimulation enables the nervous system to differentiate wishes from reality, Omega has no power of inhibiting inappropriate discharges. Omega can be employed to signal when discharges should occur (when a wished for object is actually present), but it cannot prevent discharges when they should not occur. This latter function - the inhibition of discharge - is carried out by the ego, and with variable success.

The ego's ability to inhibit discharge - and to control the concentrations of cathexes in Psi generally - derives from the fact that it is made up of countless individual neurons acting together as a system. The ego exerts its control by dispersing Q in small or moderate amounts through many specific locations in Psi. From the standpoint of Psi as a whole, propensities to discharges are a function not so much of the total amount of Q in the system as of the distribution of Q. A large total amount of Q spread evenly throughout many neurons may nowhere reach sufficient concentration to initiate a discharge; conversely, a small total amount of Q in a few neurons may initiate several discharges. The ego, defined as the overall distribution of cathexes and facilitations that regulate Q exchanges in Psi, obviously has a bearing on the frequency of discharge.

As has been shown, the ego has two interdependent components. Each of these contributes to its "strength" - i.e., its ability to inhibit discharge. The first, relatively stable component, is the pattern of preexisting facilitations. These facilitations provide well-used channels by which dangerously high levels of Q in individual neurons can sometimes be siphoned off. The second factor, which constantly varies, is the amount and distribution of Q already in the neurons of the ego. If relatively many neurons are moderately cathected, they establish what Freud calls a "side cathexis" that can draw off and dilute larger amounts of Q than the facilitations can handle by themselves. In general, then, an ego consisting of many inter-facilitated neurons is stronger than one consisting of few; thus an adult's ego is stronger than an infant's. But an adult's ego whose neurons are already partially cathected is stronger than one where they are uncathected. Figure 2 illustrates these variations in ego strength.

A. No ego. In a totally inexperienced Psi system, no simultaneous cathexes have occurred in the past, and the maximum resistance remains betwen all pairs of neurons. (In these illustrations, the number of neurons representing the Psi system is greatly reduced.) Q entering neuron X has nowhere else to go, hence accumulates rapidly and discharges.

B. Uncathected adult ego. Because of prior simultaneous cathexes, neuron pairs are variably facilitated. Some Q entering neuron X can be transmitted to neuron Z, and then to Z's associates. Hypercathexis of X occurs only when the rate of Q input to it exceeds the rate at which it can disperse Q to the ego.

C. Cathected adult ego. The facilitations in diagram B are further augmented by the effect of moderate cathexes throughout all the neurons of the ego. Q may be dispersed even more quickly from neuron X since more pathways are more open to it. Discharge may be maximally inhibited in this kind of system.

Figure 2: Variations in Ego Strength

According to Freud's model, an adaptively functioning and strong ego should inhibit discharges until a persistently cathected neuron receives indications of reality from Omega - indicating that a wished for object is actually present. Then, by some unspecified mechanism, Q from the ego may be permitted to accumulate in the neuron until it discharges and initiates the consummatory response.

The success of the ego at any given moment is a function of the intensity of the Q inputs it must deal with, as well as its inherent strength. Even an infant's rudimentary ego may be effective when levels of exogenous and endogenous stimulation are very low, and even an optimally cathected adult ego may be overwhelmed by particularly intense inputs. What determines the course and outcome of mental events at any time is thus the relationship between the ego and the Q sources with which it must deal. In general, Freud deduced the characteristics of two ideal modes of neuro-psychological functioning, depending on the nature of this relationship. When the ego is relatively unequal to its task, the resulting Psi activities are described by Freud as "primary processes;" when the ego is relatively strong and in control, they are called "secondary processes."

Primary and Secondary Processes

When the ego is weak, the Psi system is particularly susceptible to relatively small variations in the concentration and distribution of Q. While indications of quality are constantly being recorded in Omega, these indications are relatively useless to a Psi system that is incapable of inhibiting discharges. Accordingly, primary process functioning is dominated by quantitative rather than qualitative factors.

One consequence of this is that primary processes tend to be heavily influenced by endogenous factors. Although it is true that hypercathexes with exogenous Q are inhibited just as inefficiently as those with endogenous Q, exogenous stimulation is more easily avoided by reflexive flight responses. A more chronic problem is posed by endogenous excitation, which cannot be run away from but which constantly flows into Psi until the specific satisfaction it demands is provided. Thus a constant cathexis tends to be maintained in neurons representing wishes, and as these attract still more Q to themselves from other, simultaneously cathected neurons, they frequently pass the threshold for discharge. In general, then, primary Psi processes tend to be dominated by wishful considerations, and to be punctuated by frequent wish-related discharges.

Another type of discharge also frequently characterizes primary process activity. In the absence of an inhibiting or moderating ego, any neuron that receives large cathexes for purely circumstantial reasons is prone to discharge. One such class of neurons are those that are common associates of several other neurons that happen to be cathected at the same time. As a common associate, a neuron may receive small quotients of Q from several different sources at once which cumulatively cathect it beyond the threshold for discharge. Here is the neurological explanation for the overdetermination Freud found in hysterical patients. Certain ideas - such as "hands" in the case of the patient with the hand tremor - become hypercathected not because of any inherent significance of their own, but because they are associated with several significant ideas at once. And while none of the contributory ideas themselves may become sufficiently cathected to discharge, they contribute enough Q to their common associate to hypercathect it. Figure 3 illustrates this with the case of the hysterical hand tremor.

In the absence of a strong inhibiting ego, a neuron may become hypercathected simply because it is a common associate of several other concurrently cathected neurons, receiving small quotients of Q from each of them. In Freud's hysterical patient, for example, neurons representing three separate pathogenic ideas become cathected, but not to the point of discharge. Each of these neurons (representing a hand-strapping received as a child, a fright received while playing the piano, and a back massage administered to an uncle) sends out quotients of Q to neurons with which it has been associated in the past. The neuron representing "hands" is a common associate of all three, and so receives a triple dose of Q. In the absence of strong inhibition from the ego, the neuron discharges and causes the muscular activation of the hand tremor.

Figure 3: Overdetermination as a Primary Process Characteristic


Because the introduction of endogenous Q into Psi, and the interneuronal exchanges of Q within Psi occur without exciting Omega, all of these wishful and overdetermined primary process activities take place without exciting consciousness. Only the discharges themselves excite consciousness. Accordingly, the conscious experience of a person engaging in primary process activity is of a sequence of hallucination-like sensations and activities that "come from nowhere," and fail to make sense in terms of his or her previous conscious frame of reference. It is only by means of special analytic techniques, such as free association, that the overdetermined and wish-related nature of these hallucinations can be made obvious.

Secondary process activity occurs when the ego succeeds in diffusing Q among many interconnected neurons. In addition to inhibiting inappropriate discharges, this activity serves other adaptive functions by involving many different neurons in the neuro-psychological process. On a psychological level this means that many different memories and associations become aroused, constituting the basis of flexible thought and the consideration of many different possibilities for action.

Consider the following simplified example, illustrated in Figure 4. A man is hungry, but finds himself in the living room rather than the kitchen, which is where the food is. Accordingly, the neurons representing "food in the kitchen" are wishfully cathected with endogenous Q. "Living room" is what is currently experienced in reality, hence its neurons are exogenously cathected. The problem is to make the wish and the reality coincide, a goal that is made possible in reality by the disciplined associative activity of the secondary process. Cathexes from both "food in the kitchen" and "living room" are sent out in all directions, and eventually reach two common associates: the memories of past occasions when food was in the living room, and of walking from the living room to the kitchen. Both are potentially overdetermined ideas, but the strong ego is able to inhibit the concentration of cathexis in the realistically unfounded "food in the living room." "Walking from living room to kitchen" is a realistic possibility, however, and receives appropriate indications from Omega. Hypercathexis occurs, and the resulting discharges activate the actual walking. The original wish for the food in the kitchen now becomes a reality and hypercathexis of the neurons initiating eating behavior can be permitted.

An endogenously cathected wish, to have the food in the kitchen, and the exogenously cathected "reality" of being in the living room do not coincide. The ego draws off excessive Q in the wish, thus preventing discharge and hallucinatory gratification. Instead, both the wish and the reality send out small quotients of Q to many associated neurons, including two common associates: the memory of past occasions when food was in the living room, and the memory of past experiences of walking from the living room to the kitchen. The first is currently unrealistic since there is no food in the living room now; thus the ego prevents wishful hypercathexis in that neuron. "Walking from living room to the kitchen" is a realistic possibility, supported by the proper indications from Omega, however. Thus Q is permitted to accumulate there, initiating discharge and activating the adaptive response of walking to the kitchen.

Figure 4: Reality-oriented Secondary Process Functioning


The Q-dispersing properties of the ego in the secondary process are also responsible for the phenomenon of conscious thought. According to Freud, memories of specific vocalizations come to be associated with the memories of specific events. The prototypical case is the association of a scream of pain with a painful experience. Language development, for Freud, occurs when the process continues and vocal responses, or words, come to be associated with an increasing number of specific concrete memories. These word associations are important because they provide a system of neurons whose discharge can provide a relatively non-disruptive way of symbolizing and consciously representing various ideas and memories.

Consider the painful experience. If the neurons representing the experience itself were to discharge, the result would be an hallucinatory re-creation of the whole experience - an extremely unsatisfying outcome. But if the neuron representing the scream (or its more refined derivative, the descriptive word) discharges, the result is a mere vocalization which may stand as a conscious but painless symbol of the experience.

Discharges from neurons representing words thus provide the mechanism for consciously but symbolically remembering things. A cathected "primary memory" transmits some of its Q to the highly facilitated word associated with it. The ego prevents hypercathexis in the primary memory, but permits it in the word. The resulting discharge is minimally disruptive to the organism (especially when compared to the effect of a discharge from the primary memory), and brings the memory symbolically to consciousness.

The major adaptive advantage following from this activity is that both very positive and very negative memories can be reviewed "neutrally" in the thought process. Hallucinatory pleasure or pain do not follow from the word discharges, as they would discharges from the primary memories, so the subsequent associative processes can avoid being swayed by the endogenous emotional complications that pleasure and pain create. Relatively hard-headed "thought experiments" may be carried out at the level of symbolic verbal discharges, some of which will be recognized as appropriate models for adaptive "real" actions to follow.

Freud's detailed description of these secondary processes in the Project is complicated and in places ambiguous. Sometimes the model is incomplete, or its parts do not mesh quite properly. Nevertheless, three secondary process characteristics are clear enough, all made possible by the Q-dispersing capacity of a strong ego. First, emotional factors such as wishes are restricted to a guiding role in the thought process, and prevented from assuming such great intensity as to be mistaken for reality. Second, associative activity with the end goal of connecting wishes with reality is encouraged, and discharges are permitted that realistically help to achieve the wishes. Third, relatively "safe" discharges are permitted in neurons representing words, thus providing an emotionally neutral medium in which conscious thought experiments may be played out.

The secondary processes, of course, correspond with what most people regard as "normal" thought. They represent Freud's attempt to explain ordinary conscious experience. His major interest in the Project, however, was to account for incursions of primary process thinking into adult experience. The two most striking examples of this, that he discussed at some length, were dreams and hysterical symptoms.

Dreams and Hysteria

The Project was the first place Freud ever dealt systematically with the nature of dreams. Indeed, it is likely that many elements of his dream theory first occurred to him in the context of his neurological speculation for the Project, since they follow as logical deductions from his assumptions there. Circumstantial support for this assertion is provided by Freud's own report that he discovered the "Secret of Dreams" in a flash of insight on July 24, 1895 (Freud, 1954, p. 322). The "Secret" was that dreams represent the fulfilment of wishes, and the date coincides with the time Freud was most energetically involved in his neurological speculations leading to the Project.

The dream theory in the Project is based on three assumptions about the sleeping nervous system. First, the exogenous sense receptors are assumed to be almost completely closed off; thus there is great reduction in the excitation of both Psi and Omega from external sources. Second, the ego is largely depleted of Q, and hence is in a relatively weakened state. This depletion occurs partly because exogneous Q is no longer entering Psi in the normal waking quantities; and partly because consummatory activities (e.g., eating or copulation) have preceded sleep, thus discharging from the ego much of its endogenous Q as well. Third, the motor pathways usually employed for discharge are closed off. Discharged Q cannot follow the normal "progressive" route into the musculature, but must back up "retrogressively" into the sensory pathways, which are now devoid of incoming stimulation. The result is a sensation rather than a movement.

The essentials of Freud's dream theory follow logically from these assumptions. Since exogenous sources of Q have been closed off, the only energy activating Psi will be endogenous Q gradually building up and cathecting wishes. In the absence of a strong ego, primary processes will predominate in Psi. Discharges will occur in wishfully cathected neurons, and in neurons that are common associates of concurrently cathected wishes. The results, which will be sensory experiences rather than motoric acts, will be hallucinatory fulfilments of the wishes and their overdetermined associated ideas. Such is the nature of a dream.

Freud confirmed this theory, at least to his own satisfaction, by subjecting dream images to free association. As is well known from Freud's psychoanalytic works, such analysis showed dream images to be "condensations" associated with several different ideas at once, and clearly related to the satisfaction of wishes (albeit consciously disturbing and unacceptable ones).

Freud's treatment of hysteria in the Project is only partially successful. Its most effective aspects follow from a direct integration of his psychological theories about hysteria into the neurological context. In Studies on Hysteria he and Breuer had described the unconscious pathogenic memories underlying hysterical symptoms as constituting a "split off psychical group." This term denoted a group of ideas associated with one another, but which for some reason are unable to make associative contact with the normal store of ideas. Because of this dissociation, consciousness cannot flow from an idea in normal awareness to one in the split off group. Hence the ideas in the split off group are inaccessible to normal consciousness.

In the terms of the Project, this means that the neurons constituting the split off group cannot exchange Q with those constituting the ego. The split off group is not subject to inhibition by the ego's side cathexis, but instead forms a kind of miniature ego in itself. Because of its relatively small size, however, its ability to inhibit discharges within itself is also relatively small. As its neurons become cathected, dispersal of Q can occur only within the small group itself. Thus primary processes occur frequently, and the discharges into the musculature cause overdetermined physical symptoms symbolically related to the ideas that discharge.

The major failure in the Project's treatment of hysteria is its inability to explain why a sub-system of neurons should be dissociated from the ego in the first place. In short, Freud cannot deal neurologically with the phenomena of psychic defense, a fact he candidly admits: "How primary defence, non-cathexis owing to a threat of unpleasure, is to be represented mechanically - this, I confess, I am unable to say" (Freud, 1966, p. 370). Given the increasing prominence of defensive phenomena in his developing psychological theory, this particular difficulty may have been instrumental in inducing Freud to give up neurological speculation altogether.

Influence of the Project

Two years after completing the Project Freud encountered a severe challenge to his entire theory of hysteria. His theory had been based on the assumption that the pathogenic ideas underlying symptoms were actual memories of earlier traumatic events, and that the symptoms were defenses against the conscious recollection of those memories. In 1897, however, mounting evidence forced him to conclude that these were not actual memories, but fantasies. The traumatic events had never occurred in reality. How then could Freud account for these bizarre ideas, which, it was becoming clear, always entailed sexual content and always were regarded by his patients themselves as actual memories,

Although he must not have realized it at first, Freud's answer was already implicit in the Project. Hysteria was clearly a primary process phenomenon, and primary processes had been shown there to be frequently involved with the hallucinatory fulfilment of wishes. Indeed, wishes had been explicitly cited as the motivating causes of dreaming, a primary process phenomenon similar in many ways to hysteria. Thus why not regard sexual wishes which become so intense as to be mistaken for reality as the basic motivating impulses behind hysteria? As is well known, Freud went on to draw just this conclusion, with all of its far reaching implications. Although many different factors must have led him to that conclusion, including his own self-analysis, the theoretical structure of the Project unquestionably predisposed him toward it.

In spite of its heuristic value, Freud soon abandoned the Project's explicitly neurological framework in his theorizing. The problems of describing precise neurological mechanisms to account for complicated psychological processes such as defense were immense, and in any event Freud found he could describe the essentials of his model of the mind in purely psychological terms. Just four years after the Project, in his masterwork The Interpretation of Dreams, Freud could write: "I shall entirely disregard the fact that the mental apparatus with which we are here concerned is also known to us in the form of an anatomical preparation, and I shall carefully avoid the temptation to determine psychical locality in any anatomical fashion. I shall remain on psychological ground" (Freud, 1953/1900, p. 536).

Remain on psychological ground he did, and during the rest of his long life few people suspected even the existence of the Project's speculations. Nevertheless, the careful consideration of just a few major concepts from mature psychoanalytic theory reveals the Project's lingering influence. Freudian "instincts," for example, are the direct descendents of endogenous Q, and "psychic energy" is the successor of the general notion of Q. "Cathexis" retains an important place in Freud's technical vocabulary, referring to the attractive and organizing influence of an idea (rather than a neuron) on the overall thought processes. The term "ego" disappeared from Freud's technical vocabulary for several years following the Project, only to return in 1923 in a familiar guise: as the name of a psychic agency whose function is to control instinctual processes and reconcile wishes with reality. The "primary and secondary processes" are consistent features in Freud's psychoanalytic theory. The former always denote unconscious, overdetermined, and instinctually dominated modes of thought that are only sometimes superseded by the conscious, logical, and reality-attuned activities of the latter. It is unlikely that any of these ideas would have assumed the final shape they did if they had not originated in the mechanistic, neurological speculation of the Project.



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