Memory Explanations (Part 5)

Gestalt familiarity

When the overall perceptual configuration of the present stimulus array is similar to one experienced previously, this gestalt correspondence could trigger a deja vu (Reed, 1974). Recall the example of the first visit to a friend’s home as an illustration; it is not the grandfather clock in the corner of your friend’s living room that is familiar, rather the familiarity comes from the fact that the room has a layout similar to the one in your aunt’s house: a sofa to the right of the love seat with a stairway to the left going up the wall, a grandfather clock against the back wall, and an Oriental rug on the floor. None of the elements in the newly entered living room is identical to one from the previous context, but the particular configuration of elements fits the same template. Sno and Linszen (1990) suggested that different scenes and individuals often overlap in many structural details, and when perception is degraded the general framework of a prior experience may overlap considerably with the present one. Using similar logic, Levitan (1969) suggested that in recognizing an entire scene or setting, people automatically break it down into simpler perceptual forms such as cubes, triangles, circles—a process similar to what cubist painters did. This is also related to Biederman’s (1987) notion that all perceptual experience can be reduced to a relatively small set of geons, which represent the range of all primitive perceptual forms. Thus, the untoward sense of familiarity eliciting deja vu in an unfamiliar setting may arise because the arrangement of the reduced perceptual forms matches those from a prior experience.

Gloor (1990) also used this gestalt analogy and tied his speculation to deja vu experiences in the preseizure aura of TLEs. Drawing on the parallel distributed processing model of Rumelhart and McClelland (1986), Gloor suggested that the erratic firing of neurons in the temporal lobe prior to the seizure gives rise to spurious matches between the present visual scene and prior visual experiences. For both Sno and Linszen (1990) and Gloor, perceptual degradation was more likely to precipitate such configural matches. Assuming that fatigue or stress are associated with such reduced perceptual precision, this fits with the earlier suggestion of an association between fatigue and deja vu.