Inside the mind is a spatial sketchpad that can form a picture, and very often the image it forms is an item of food or drink that the person craves. Like the old Etch-A-Sketch toy, the mental screen can only hold one picture at a time. If you take the toy in your hands and shake it, the sketch disappears.
Back in the 1990s, J. G. Quinn (University of St. Andrews, Scotland) and Jean McConnell (Staffordshire University, U.K.) discovered that food cravings are intimately connected with the ability to form a mental image (PDF). If the mental picture can be made to dissolve, the craving (PDF) is weakened.
As an article published by the British Psychological Society phrased it:
This method has been shown to produce selective disruption of the storage of visual material in working memory… The visual interference technique devised by Quinn and McConnell is based on a continuous display of dynamic visual noise during the processing of the primary task. The underlying postulate is that dynamic visual noise disrupts visual imagery by gaining obligatory access to the visual cache of working memory (Quinn & McConnell, 1999), or to the process of generating an image from a verbal description.
It’s not an exact analogy, but visual interference or dynamic visual noise accomplishes something very much like shaking the Etch-A-Sketch. It disrupts the picture — but, what is more, it replaces the picture with a better one. A moving display, even “visual white noise,” captivates the attention, but conveys no message. With something to watch but no content to assimilate, the mind can relax.
Relaxation reduces stress, and the diminution of stress, in turn, reduces cravings. The discoveries made in this area are helping patients with all kinds of addictions, and keeping addictions from developing.
There is a branch of psychology called Elaborated Intrusion theory (PDF). A paper called “Conscious and Unconscious Processes in Human Desire,” written by Jackie Andrade, Jon May, and David Kavanagh, gives a very convincing diagram, along with a thorough explanation that can’t be quickly summarized.
Nevertheless, here are some excerpts:
Imagery is closely linked with emotion… We imagine unwrapping a bar of chocolate and feel the anticipated pleasure of eating it. It is the importance given to imagery that particularly distinguishes EI theory… Episodes of desire are triggered by a range of environmental, physiological or cognitive cues… Desire images are an example of ‘hot cognition’; they have affective content.
The bottom line here is that “selectively blocking the cognitive processes needed for imagery leads to reduced desire.” One way of selectively blocking is to ask the experimental subject to conjure up a neutral picture, like a field full of wildflowers. This second visualization counteracts the first image by pushing it aside. Another way of selectively blocking is to present a neutral yet interesting visual stimulus for the brain to latch onto, keeping it too busy to imagine chocolate-covered bacon.
An important concept here is that “unconscious and conscious processes in desire are based in different but interlinked brain systems.” In saying this, the authors are building on the work of J. Blackburn as reported in an unpublished MSc thesis in 2006:
Preliminary support for distinct roles of liking and wanting comes from a qualitative study of people who had recovered from eating disorders. They reported feeling hungry, but not craving food: They ‘wanted’ food, but didn’t ‘like’ it and thus, did not crave it by elaborating thoughts about food. Instead, when physiologically hungry, they consciously thought about the positive aspects of being in control of their food intake, and of not putting on weight. They were ‘wanting’ food but ‘liking’ the self-control associated with not eating.
Then the authors get into brain imaging, and state that further testing is needed to verify “the prediction that brain regions underpinning visuospatial working memory play a key role in desire,” or, as we are accustomed to calling it, craving. They talk about bottom-up processes and top-down processes, both of which can enable conscious desires, or cravings.
They even get into questions of philosophy. But they are sure of one thing:
Not only can competing cognitive demands prevent an episode of desire beginning, they can also weaken or interrupt a desire that is already established, as shown by the effects of competing tasks on craving in the laboratory. This finding is important clinically: Selective cognitive blockade of the controlled processes needed for desire can potentially reduce craving to the point where it is tolerable, helping to sustain quit attempts.
Your responses and feedback are welcome!
Source: “Visuospatial working memory and the processing of spatial descriptions” (PDF), psy.ed.ac.uk
Source: “Conscious and Unconscious Processes in Human Desire” (PDF), theassc.org
Image by star5112, used under its Creative Commons license.
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