Sleep

Sleep matters to Freud’s account of dreams not simply as their setting but as a condition that alters the work of the mind. The sleeper turns away from the external world, yet remains reachable by it; thought and bodily sensation continue to exert pressure, while the mind’s changed operation can turn those pressures into dream-images. Freud therefore distinguishes the physiology of sleep from the psychological question he pursues: how sleep makes dreaming possible, and how dreaming can in turn help maintain sleep.

Scope and the sleeping state

Freud deliberately limits the inquiry. Earlier writers commonly discussed sleep and dreams together, often extending the comparison to hallucinations, visions, and other altered states. He instead organizes his account around particular problems of dream-life, treating this psychological investigation as distinct from a comprehensive history of sleep. Sleep, he says, is essentially a physiological problem; nevertheless, any characterization of it must include changes in the conditions under which the psychical apparatus functions. His decision to set aside much of the literature on sleep is thus a boundary of method, not a denial that sleep shapes the dream.

That distinction also separates Freud’s project from the competing explanations he surveys. Theories such as Delboeuf’s maintain that full psychical activity continues during dreams, with sleep’s different conditions producing results unlike waking thought. Freud objects that this view does not explain why the apparatus should keep working in circumstances that seem to call for sleep without dreams, or awakening when disturbed. Other theories posit a general lowering of psychical activity, weakened connections, and impoverished usable material. Freud uses the contrast to frame his own question: rather than assuming either an intact waking mind or a uniformly disabled one, he examines how sleep changes the conditions and direction of mental activity.

Withdrawal without complete isolation

The effort to sleep involves closing the eyes and shielding the other senses from stimulation, as in the observation of an invalid whose remaining sensory gateways were cut off before he fell asleep. But the attempt at isolation is never complete. Light may reach the eyes, sounds and odors may intrude, and changes in posture, pressure, contact, or temperature can continue to affect the sleeper. Freud takes the possibility of waking in response to stronger stimuli as evidence that the psyche remains in contact with the world outside the body.

Such impressions can become material for dreams. A sound of thunder may take dream form as a battle; a cock’s call may become a human cry; a creaking door may suggest intruders. Losing bedclothes, having the feet extend over the edge of the bed, or getting the head beneath a pillow can likewise be represented as being unclothed, standing at an abyss, or threatened by a heavy mass. These examples show how external stimulation can be incorporated into dream-content, but Freud does not treat it as a complete explanation of ordinary dreaming. Illness can also supply unusual bodily stimuli, yet dreams occur in healthy people and cannot depend on disease as an indispensable condition. The question, for him, is not merely what produces exceptional dreams, but how the ordinary dream-life of healthy sleepers is stimulated.

Sleep’s relation to the outside world is also a matter of interest, not just sensory strength. Burdach’s observations suggest that some impressions can soothe a sleeper: a miller may sleep to the sound of his mill, while someone who relies on a night-light may be unable to sleep in darkness. Conversely, a sleeper may awaken when an expected sound ceases or a valued light is extinguished. The psyche is withdrawn from the world, Freud argues, but sensation does not cease; associations and importance help determine which impressions pass through.

Memory, perception, and dream reality

Sleep changes the conditions under which an image can be tested against waking reality. Freud discusses the view that dreamers take images for real because, removed from the external world, they have no other impressions with which to compare them. Yet the difficulty is not simply lack of comparison: in sleep, the psyche has lost the ordinary means of testing whether an image is objectively real. A dream can even provide apparent confirmation of its own images, such as the sensation of touching a rose that is seen, without thereby establishing that the dreamer is awake. In practice, awakening supplies the decisive contrast: the sleeper recognizes the preceding experience as dream when awareness returns to the body lying in bed.

The mind’s estrangement from dream activity is part of the same problem. Although dreams are assumed to arise from the dreamer’s own psychical activity, they can feel alien, as though a dream had come rather than been made. Freud considers the proposal, associated with Gustav Theodor Fechner, that dream and waking activity occupy different psychical locations. He rejects an anatomical reading in terms of distinct brain regions, but allows that the idea may prove useful when applied to a psychical apparatus composed of agencies arranged in sequence. Sleep, in this account, is not simply a dimmer version of waking life: it changes the conditions by which mental activity is organized and recognized.

Dreams also vary greatly in how they survive awakening. A dream that is vivid in the morning may fade over the day into fragments; a person may remember having dreamed without recalling the content, or may lose even the recollection of dreaming. Yet some dreams remain unusually durable. Freud reports analyzing patients’ dreams from twenty-five or more years earlier and remembering one of his own from at least thirty-seven years before, still fresh in memory. The contrast prevents dream-forgetting from being reduced to a simple rule: forgetting is a complex process, and remembered dream-content is the means by which the dream becomes available for investigation.

Sleep, regression, and the function of dreaming

Freud’s account of regression connects the sleeping state to the dream’s sensory form. In dreaming, an idea can return to an image; Freud proposes that sleep makes this reverse movement possible in part because the current flowing toward movement from the perceptual end of the psychical apparatus comes to an end. During the day, that forward current can prevent excitation from travelling backward. At night, when it ceases, the path back toward perception is open. Freud presents this as a conjectural explanation, not a settled physiological finding, and distinguishes it from waking hallucinations, which he also interprets as thoughts transformed into images but associates with suppressed or unconscious memories.

Sleep also changes the preconscious system, which ordinarily has access to consciousness and to movement. Problems left unfinished, thoughts that remain unsettled, concerns, rejected material, unconscious impulses stirred during the day, and even unimportant impressions may continue to press for expression after a person has decided to sleep. Freud groups these as different kinds of day residue. Their entry into a dream is not unrestricted: because the usual path from preconscious excitation to consciousness is impeded, the thoughts must obtain reinforcement from the unconscious and follow the same indirect route taken by unconscious excitation.

The dream then becomes perceptible and can attract some of the preconscious energy that had been at rest. That attention allows the dream to undergo secondary revision, which imposes a measure of coherence and intelligibility, even as the sleeping mind’s interest in ordinary thought is reduced. Freud’s account therefore assigns sleep an active role in the dream’s formation: it limits one route of mental activity, leaves other excitations seeking expression, and alters the conditions by which the resulting images reach awareness.

The most consequential claim is that dreaming can help preserve sleep. An unconscious excitation left entirely to itself might eventually discharge in movement. In Freud’s model, it instead takes a regressive path and forms a dream; the preconscious then binds that excitation with a comparatively small expenditure of activity. The dream thus acts as a compromise between psychical systems: it gives an unconscious wish a form while helping the preconscious remain at rest. Freud calls dreaming a safety-valve and a guardian of sleep, not an interruption of it by definition. The arrangement can fail if a wishful dream disturbs the preconscious too forcefully; in that case the dream is interrupted and the sleeper wakes. Awakening marks the breakdown of the compromise, not proof that dreaming has no sleep-preserving function.