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Defense Mechanisms: Neuroscience Meets Psychoanalysis

Suppression and dissociation, two psychoanalytic defense mechanisms, are now studied by modern neuroscience














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Evidence of Suppression
Linking suppression to widely accepted brain mechanisms involved in behavioral control moves this concept from the domain of the psychoanalyst’s couch to the physical realm of the brain.

A different form of suppression, known as visual perceptual suppression, occurs when an object—or part of one—is not consciously seen even though the image is always clearly visible. A common example is the bistable figure, such as the drawing of the cube, the vase-face or the duck-rabbit in the triptych illustration above. The eyes see the same lines and shapes on the page, but what you consciously see in your head changes from the duck to the rabbit and back again. When the image of the duck is being consciously seen in your mind’s eye, the image of the rabbit is “suppressed,” and vice versa.

Another example of visual suppression is binocular rivalry. Here two ifferent images are simultaneously present, one in each eye. Say a photograph of a smiling girl is projected into your left eye and an image of a car is projected into your right eye. Rather than appearing as the girl superimposed on the car, the two pictures rival for conscious access, and one will suppress the other briefly. For a few seconds you will see the girl’s face; suddenly, patches of the car begin to shine through until the face is entirely gone, and you’ll see only the car. Subsequently, the smiling eyes will break through the automobile, and it will disappear to be replaced by the girl’s face, and so on in a never-ending pas de deux.

So although the physical input to the eyes always remains the same, your conscious perception of it changes from one moment to the next and back again. Bistable percepts are ideal for tracking the footprints of consciousness in the human brain using functional brain ­imaging [see “Rendering the Visible Invisible,” by Christof Koch; Scientific American Mind, October/November 2008].

Provided the eyes don’t move or blink, this ceaseless dance is under only very limited voluntary control. Thus, from the point of view of psychoanalysis, it would be more proper to call this perceptual repression rather than perceptual suppression. Whether the neural mechanisms underlying visual perceptual suppression and repression are related to those underlying psychodynamic suppression or repression remains to be determined.

Emotions Apart
Dissociation is another controversial psychological state in which thoughts, emotions, sensations or memories are separated from the rest of the psyche. Originally championed by French psychiatrist Pierre Janet, dissociation can occur in healthy individuals such as when you blank out for a mile or two while driving along a freeway, become completely absorbed by a book or movie, or find yourself walking into a room in your house only to forget why you ventured there in the first place.

More extreme forms of dissociation manifest themselves in mental diseases such as dissociative identity disorder (DID)—formerly known as multiple personality disorder—which involves the presence of two or more distinct identity states. These states are characterized by different emotional responses, thoughts, moods and perceived self-images that recurrently and alternately take control of a patient’s behavior and consciousness. DID is considered to be a result of identity fragmentation rather than proliferation of separate personalities. So patients do not have more than one personality (a proliferation of selves), but rather they have less than one (a fragmented self).

Dissociative identity disorder is often associated with severe and prolonged childhood trauma (such as neglect or emotional or sexual abuse) and develops as a way to cope with an overwhelming situation that is too painful or violent to assimilate into one’s conscious self. The person literally “goes away” in his or her head to flee from the anxiety-producing experience from which there is no physical escape. This dissociative process allows traumatic feelings and memories to be psychologically separated off so that the person can function as if the trauma had not occurred. While in one mental state, the patient has access to traumatic autobiographical memories, say of a rape, and intense emotional responses to them. But when in her other state, she claims not to recall anything related to her rape. This defensive use of dissociation prevails long after the traumatic experiences have ended.


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  1. 1. technophile50 01:55 PM 4/14/09

    "But when in her other state, she claims not to recall anything related to her rape." I think it is clear from the rest of the article that she isn't just claiming not to recall, but in fact does -not- recall, because involuntary defensive neurobiological processes are blocking recall. It's not as though the room where these memories are stored has the lights off, but as far as she is aware (in this state) this room doesn't exist.

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  2. 2. ramesam 09:39 PM 4/14/09

    Article says: "Dissociation may be the result of a disruption of certain connections among brain regions. Hence, dissociative disorders may result from the failure of coordination or integration of the distributed neural circuitry that represents subjective self-awareness."

    Comment: It may be added, just for completion, that not merely the 'integration of the distributed neural circuitry' but also the 'architecture' of the neural circuitry as well as the slow electrical activity of the glial cells (e.g. astrocytes) etc. will have an influence as recent research papers indicate.

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  3. 3. verdai 08:19 PM 5/19/09

    This is Soooo widespread, that it isn't funny.

    In fact, I am terribly sick of putting up with it.
    People really need to recognize it; and any thing that will further that end such as research, should be used in force.

    Reply | Report Abuse | Link to this
  4. 4. verdai 08:19 PM 5/19/09

    This is Soooo widespread, that it isn't funny.

    In fact, I am terribly sick of putting up with it.
    People really need to recognize it; and any thing that will further that end such as research, should be used in force.

    Reply | Report Abuse | Link to this
  5. 5. verdai 08:19 PM 5/19/09

    This is Soooo widespread, that it isn't funny.

    In fact, I am terribly sick of putting up with it.
    People really need to recognize it; and any thing that will further that end such as research, should be used in force.

    Reply | Report Abuse | Link to this
  6. 6. debralovesgospelmusic 10:08 PM 12/7/09

    I work in a prison with the mental health population. I have seem so many cases of women who during a "disassociated" mental state, committed a crime. They do not have memory of it. They have no reason to lie as they are in prison for life. We truly must work to understand the brain, mind and mental states so that we may help this problem. These women are living desperate lives...because of actions, they don't even remember.

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  7. 7. lookingaround in reply to technophile50 01:56 PM 5/8/10

    I agree with technophile50's comment and gave light to a better understanding. It's true, for the people the room just does not exist at all.

    I think, it's important, according to the last comment of debralovesgospelmusic, that we remember the suffering experienced by someone with DID, as the personality moves here and there, rooted in a fragmentation...Expose the benefits of the talking cure in some patients would be interesting too.

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  8. 8. kayfgibbs in reply to technophile50 07:06 PM 3/13/11

    I discovered information at The Veteran's Hospital in Durham, NC which stated that dissociation was recognized by writers. Of course it is, they have a piece or your mind. I have experienced dissociation many times and not just because I endured some trauma. I have had problems locating things in my apartment because my neighbor has jacked me up into another state, maybe psychologists call it a paradigm shift, I don't know. For three years I completely lost memories of repeated sexual abuses I endured during my military enlistment. I even acted some of them out not realizing they were actually repressed memories of my assaults. It wasn't until 1989 that I began to put things together. Even bits of the event were put into a film.

    So, do we really dissociate or are we just having our memories ripped off?

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  9. 9. kayfgibbs 07:09 PM 3/13/11

    "I even acted some"
    Correction - acted out

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