When emotion becomes an image
Ernest Hartmann and the Central Image
Ernest Hartmann proposed that dreaming makes broad connections through memory, guided by the dreamer’s dominant emotion. At the heart of many memorable dreams is a Central Image: a powerful picture that gives the emotion a visible context.
A theory of imagery, emotion and connection
How to approach Hartmann on dreams
Ernest Hartmann (1934 to 2013) was an American psychiatrist, sleep researcher and professor at Tufts University School of Medicine. His work ranged from the biology of sleep and the experience of nightmares to personality, creativity and the metaphorical structure of dreams.
Hartmann called his mature account the Contemporary Theory of Dreaming. It is a psychological theory of dream form and possible function. It is not a complete account of REM sleep, and its proposed adaptive function remains less firmly established than its descriptive findings about imagery and emotion.
The Central Image is not a key that unlocks a fixed meaning. It is a candidate picture-context for the emotion organising the dream.
The Contemporary Theory in four movements
1. A mental continuum
Focused waking thought, reverie, daydreaming and dreaming differ in how tightly mental activity is constrained.
2. Broad connections
Dreaming permits wider connections among memories than the goal-directed mode usually used while awake.
3. Emotion guides
The dreamer’s dominant emotional concern influences which memories connect and which imagery becomes central.
4. Imagery contextualises
A strong image can provide a concrete visual context for an emotion that is otherwise difficult to formulate.
Hartmann sometimes described dreaming as hyperconnective. This means connections are comparatively broad and less restricted, not that dreaming has limitless access to memory or that every apparent association is psychologically important.
The emotional heart of the dream
What is a Central Image?
A Central Image, also called a contextualising image, is a powerful, striking and dream-defining image. It may be a single scene, object or event, such as an overwhelming wave, a house split open, a creature trapped in ice or a bridge collapsing into darkness.
Hartmann proposed that the form of the image pictures the quality of the underlying emotion, while the image’s intensity relates to the emotion’s strength. The image does not merely label fear, grief or vulnerability. It constructs a situation in which that feeling has scale, movement, distance and consequence.
The image does not say “I feel overwhelmed.” It creates a world in which overwhelming becomes visible.
The tidal wave example
Hartmann repeatedly used the image of an approaching tidal wave to illustrate terror, helplessness or emotional overwhelm after trauma. It is memorable because it turns the relation between a vulnerable person and an immense force into a single scene.
This does not make water a universal sign of trauma. The same emotion may be pictured as fire, collapse, pursuit or endless falling. A wave may also derive from recent experience, bodily sensation or ordinary memory. Image, dream context and waking circumstances must be considered together.
How Central Image intensity is rated
Researchers using Hartmann’s scale judge the intensity of the strongest image in a written dream report. High ratings are associated with descriptions such as powerful, vivid, bizarre, detailed or clearly set apart from the rest of the dream. Independent judges can be trained to apply the scale with useful agreement.
Low intensity
No image clearly dominates, or the imagery is ordinary, indistinct and weakly described.
Moderate intensity
A distinct image stands out but is not exceptionally powerful, unusual or elaborated.
High intensity
One forceful image organises the report and is exceptionally vivid, striking or emotionally compelling.
The scale measures features of reported imagery. It does not directly measure an emotion in the brain, and the dreamer’s remembered report is not identical to the original dream experience.
Trauma and transformation
From replay towards contextualisation
Immediately after trauma, some dreams closely resemble aspects of the event. Hartmann argued that, over time, dream imagery often becomes less literal and connects the emotion with other memories and metaphorical situations. Terror may become an attacking force; vulnerability may become an injured animal; grief may become a landscape torn apart.
He proposed that this wider connecting helps integrate the event into emotional memory. This is a functional hypothesis, not a demonstrated rule. Recurrent post-traumatic nightmares may remain literal, distressing and disruptive, and continued repetition should not be romanticised as healing in progress.
A trauma-related dream may express, repeat, transform or recombine experience. No single pathway should be assumed for every dreamer.
The before-and-after 9/11 study
Hartmann and Tyler Brezler examined dream journals kept by 44 people in the United States who had recorded dreams for years. For each person, ten consecutive dreams before 11 September 2001 were compared with the first ten recorded afterwards. The reports were randomised and rated blind.
What changed
Central Images were more frequent and more intense in the dreams recorded after the attacks.
What did not change
Dream length, overall vividness, dream-likeness and bizarreness did not show the same increase.
What was absent
There was no increase in aeroplanes or tall buildings and no exact replay of the televised attacks.
Interpretive limit: this naturalistic study supports an association between a collective emotional event and rated dream imagery. It does not prove that Central Images performs emotional integration or identifies a particular emotion in every report.
Dreaming as connection-making
In focused waking thought, attention follows a task and inhibits many remote associations. Hartmann proposed that dreaming loosens these constraints. Memory fragments can connect through emotional similarity even when they are separated by time, place or literal subject matter.
The loss of a job might connect with an old memory of being left behind, a collapsing building from a film, and a childhood journey through an empty station. The resulting dream is a new construction. It need not reproduce any source faithfully to organise them around exclusion, insecurity or loss.
A new connection can be psychologically meaningful without being a coded message or evidence that dreaming was designed to solve a problem.
A worked example: the glasshouse
I am inside a vast glasshouse as a storm begins. Every pane bows inward. I try to hold the walls apart with my hands while people outside continue walking as if nothing is happening.
The glasshouse under pressure is the likely Central Image. It could contextualise exposure, fragility, impossible responsibility or the fear of collapse while remaining unseen. The surrounding action helps specify the relation: the dream self alone tries to preserve a transparent structure while others do not respond.
Those formulations should be offered as questions. The dreamer’s associations, recent events and wider dream series may support, alter or reject them.
Thick and thin boundaries
Hartmann used boundaries to describe the degree of separation among thoughts, feelings, identities, memories, sensory experiences and interpersonal positions. Thin boundaries were associated with openness, absorption, vivid imagery, dream recall and greater overlap among mental categories. Thick boundaries were associated with clearer separation, order and focused organisation.
Thinner boundaries
More permeability between categories and experiences, often with greater dream recall and more intense reported imagery.
Thicker boundaries
More separation among categories and experiences, often with a more structured and focused cognitive style.
Caution: these are dimensional descriptions, not diagnoses or fixed personality types. Boundary scores overlap with established traits such as openness and neuroticism, and the concept should not be used to rank psychological health.
What does the evidence support?
| Claim | Current appraisal | Reason |
|---|---|---|
| Strong emotional events can alter dream imagery | Supported | The blinded 9/11 comparison found increased Central Image frequency and intensity without increased report length or general vividness. |
| Central Image ratings can be applied reliably | Supported with training | Studies report useful agreement between independent raters applying the scale. |
| Memorable dreams tend to have stronger central imagery | Supported in small studies | Dreams judged important or outstanding received higher Central Image intensity ratings. |
| The scale measures one single construct | Questioned | Independent factor analysis suggests the scale may contain at least two components rather than one unitary dimension. |
| Central Images accurately measure underlying emotion | Plausible but indirect | Image intensity relates to trauma and emotion variables, but ratings do not directly measure the generating emotional process. |
| Dream connections integrate emotion adaptively | Interesting hypothesis | The proposed function is difficult to isolate from other sleep and memory processes and has not been conclusively demonstrated. |
Claims requiring caution
- One image, one emotion: a dream may contain mixed emotions, several salient images or no clear Central Image.
- Intensity equals strength: vivid reporting can be shaped by memory, verbal style, interest in dreams and the audience receiving the report.
- All dreams are new creations: dreams frequently recombine memory, but some trauma nightmares closely reproduce major features of the event.
- Integration equals recovery: a changing dream may accompany adaptation, but change alone does not establish therapeutic benefit.
- Thin boundaries explain creativity: correlations do not show a single cause, and thinner boundaries also overlap with distress-related traits.
- Metaphor supplies diagnosis: an evocative image does not identify a disorder or verify the history imagined behind it.
Using the Central Image clinically
- Ask which image remains most vivid or seems to organise the dream.
- Describe its scale, movement, atmosphere, position and effect before assigning meaning.
- Explore what emotional situation the image might make visible.
- Invite the dreamer’s associations and treat disagreement as useful information.
- Compare recurring image-relations across dreams without relying on a symbol dictionary.
- Notice whether the dream moves from literal repetition towards broader contexts, while avoiding a predetermined recovery narrative.
This use is exploratory. It may support language for an emotion, but it is not a validated diagnostic procedure and should not override the dreamer’s understanding or current clinical needs.
Nightmares, trauma and safe pacing
A powerful Central Image can be compelling, but intensity is not an instruction to intensify therapy. With trauma-related nightmares, work should be paced to consent, stability, sleep disruption, dissociation risk and the person’s ability to remain oriented to the present.
Evidence-based nightmare treatments such as imagery rehearsal therapy deliberately change and rehearse a nightmare script. This is different from Hartmann’s descriptive theory of how dream imagery may contextualise emotion. One should not be presented as proof of the other.
Hartmann in the developing field
| Approach | Primary emphasis | Relation to Hartmann |
|---|---|---|
| Freud | Wish, conflict and transformation by dream-work | Hartmann replaces disguised fulfilment with emotion-guided image construction. |
| Jung | Compensation, symbolic development and archetypal pattern | Both value powerful images, but Hartmann seeks a more directly relatable link with emotion. |
| Perls | Enactment, awareness and re-ownership | Perls asks the dreamer to become the image; Hartmann asks what emotional context it pictures. |
| Hall | Conceptions and repeated content patterns | Hall analyses stable series; Hartmann emphasises emotionally dominant imagery and broad connection. |
| Hartmann | Emotion-guided connections and the Central Image | The dream is a new construction that may weave emotionally related memories together. |
Hartmann’s contribution to metaphor
Emotion given shape
Hartmann placed metaphor at the meeting point of emotion, imagery and memory. Overwhelm becomes a wave. Fragility becomes glass under pressure. Grief becomes a broken landscape. The image carries an affective relation that cannot be reduced to a single abstract label.
In his later work with Robert Kunzendorf, Hartmann used the term thymophor for the translation or carrying-over of emotion into imagery across dreams, poetry, art and memory. The concept is theoretically suggestive, though it should not be mistaken for a separately established brain mechanism.
Questions for exploring a Central Image
- Which image stays with you most strongly?
- What is happening spatially: approaching, enclosing, falling, separating, exposing or carrying away?
- What emotional situation does this image make possible to see?
- Does the image fit one emotion or a mixture of emotions?
- What memories or waking concerns connect with it without forcing an exact match?
- Has a similar emotional relation appeared in other images or dreams?
- What interpretation would the dreamer reject, and what can be learned from that rejection?
Research and further reading
- Hartmann, 2010: The Nature and Functions of Dreaming.
- Hartmann: Emotion Guides the Dream and the Central Image.
- Hartmann: A Dream Is a Creation, Not a Replay.
- Hartmann: The Functions of Dreaming.
- Hartmann: The Tidal Wave Dream.
- Hartmann and Brezler, 2008: A Systematic Change in Dreams after 9/11/01.
- Hartmann and Kunzendorf, 2006: Central Images in recent, outstanding and earliest dreams.
- Hartmann and Kunzendorf, 2006: Boundaries and Dreams.
- Hartmann, 1989: Boundaries of Dreams, Boundaries of Dreamers.
- Levin, Gilmartin and Lamontanaro, 1998: boundary thinness and visual-spatial processing.
- Zborowski and colleagues, 2003: personality correlates of the Hartmann Boundary Questionnaire.
- Schredl and colleagues, 2009: boundaries, dream recall and nightmare frequency.
- Bilsborrow, Davidson and Scott, 2013: factors in Hartmann’s Central Imagery Scale.
- Hartmann and Kunzendorf, 2013: emotion translated into imagery in dreams and art.
A final perspective
Hartmann’s Central Image offers a disciplined way to notice how emotion acquires visual form. His research supports a relationship between emotional events and the intensity of dream imagery, while his wider claim that dreaming adaptively integrates memory remains a developing hypothesis. The theory is most useful when the image opens inquiry rather than closing it with a predetermined meaning.
This page is for education and critical discussion. Dream interpretation is exploratory rather than diagnostic. Disturbing, recurrent or trauma-related dreams may warrant support from an appropriately qualified health professional.