Uke 47

Fantasi og virkelighet

University of Wisconsin-Madison har eksperimentelt påvist at nevronene kommuniserer i motsatte retninger i dagdrømmeri og virkelighetsoppfatning.

Dette synes jeg stemmer godt overens med Antonio Damasio's beskrivelse av bilder av nå, bilder av fortid og bilder om framtid (se tekstboks).Da kan det være slik at det er de samme nevronene som engasjeres både i dagdrømmeri og oppfatning av nåtidige hendelser, men samvirket mellom dem foregår på ulik måte.

For oss selv er de like virkelige.

Saken var også omtalt i Science Daily, med henvisning til artikkel i tidsskriftet Neuroimage.

Images of now, the past, and the future

The factual knowledge for reasoning and decision making comes to the mind in the form of images. Let us look, however briefly, at the possible neural substrate of those images.

If you look out the window at the autumn landscape, or listen to the music playing in the background, or run your fingers over s smooth metal surface, or reading these words, line after line down this page, you are perceiving, and therefore forming images of various sensory modalities. The images so formed are called perceptual images.

But you may stop attending to the landscape or surface or text, distract yourself from it, and turn your thoughts somewhere elsewhere. Perhaps you are thinking of your Aunt Maggie, or the Eiffel Tower, or the voice of Placido Domingo, or what I just said about images. Any of these thoughts is also constituted by image, regardless of whether they are made up of shapes, colors, movements, tones, or spoken or unspoken words. Those images, which occur as you conjure up a remembrance of things past, are known as recalled images, so as to distinguish them from the perceptual variety.

By using recalled images you can bring back a particular type of past image, one you formed when you planned something that has not yet happened, but that you intend to have happen, for example, reorganizing your library come this weekend. As the planning process unfolded, you were forming images of objects and movements, and consolidating a memory of that fiction in your mind. Images of something that has not yet happened and that in fact never come to pass are no different in nature from the images you hold of something that already has happened. They constitute the memory of a possible future rather than the past that was.

These various images—perceptual, recalled from real past, and recalled from the furure—are constructions of your organism's brain. All you can know for certain is that they are real to your self, and that other beings make comparable images.