Paint the Town *insert hue*

Dear Yana,

                I’ve been on an out-of-town trip recently and I noticed a curious thing – whenever I recall all the different places I went to, there’s always a certain color formed in my head that is associated to one scene. When I recalled the time I went to the beach, I see the color blue; that time when I went hiking in the mountain, I see green; when I went back to the city, I always remember it having a gray hue. I understand that these different scenes have their own characteristic color that may be due to the different elements and objects found in them. What I am interested in is how my memory for these scenes seem to be associated with every day images, giving each color a “character”. When I see gray objects, I think of the hussle and bustle of city life; when I see green objects, it reminds me of taking that hiking trip; when I see blue, I am reminded of the cool and fresh breeze on the beach. 

How does this happen?

Senserely yours,

Paris Hilton

Dear Paris Hilton,

Thank you so much for writing and supporting our online blog! In order to address your question, it is first important to explain how color contributes to memory, particularly memory on the information in a natural scene.

In a study done by Wichmann, Sharpe, & Gegenfurtner (2002), identified several factors that contribute to recognition memory for color images. They have found that surface property color does play an important role in recognition memory for natural scenes. Some of the factors they have identified are

     1) Color Information facilitates storage in memory (cognitive facilitation)

-          At least for complex natural images, surface property color is stored in memory

-          There is an interaction between conceptual prior knowledge about scenes and the benefit color has to memory retention

-          Sensory information (surface color) and conceptual knowledge must not be in conflict for the benefit to occur, as evidenced by the fact that the recognition memory advantage disappears for falsely colored images of natural scenes (dependent on the color congruence of presented images with learned knowledge about the color pattern of a scene)

-          There exists two memory components explaining the effects of color on human memory: 1) achromatic object system based on the structure of the scene, and 2) surface-based episodic memory system storing color information

               2)  Color Increases Attention

          3) Color helps in improving segmentation (sensory facilitation)

-          One example of how color facilitates scene segmentation and thus, recognition, is seen in how for landscapes and rock formations, the color information appears superficially and rather redundant. Whereas it appears highly important for flower images. One can say that the surface property of color is much richer for flowers than for rock formations). Nevertheless, all objects can benefit from the chromatic information

-          The study shows that the extraction of chromatic information must be very fast and that color is being processed faster than most other features. This presents a conflict with results from past research where processing of color is seen to be slower in the visual cortex (Munk, Nowak, Girard, Chounlamountri, & Bullier, 1995 as cited in Wichmann, Sharpe, & Gegenfurter, 2002).

-          Color recognition memory for images of natural scenes are superior to that for black-and-white images if the same scenes for presentation times as short as 16 ms (Gegenfurter & Rieger, 2000 as cited in Wichmann, Sharpe, & Gegenfurter, 2002).

Thus, we can see that color does facilitate memory. This may help explain the fact that when you recall scenes in your mind, there is always that characteristic color that is associated with a scene (e.g. blue – beach, green – mountain, gray – city). To further describe how color facilitates recognition of a scene, we now focus on how memory can help in the recognition of scene gist and of scenes in general. The gist of the scene or scene gist refers to a general description of a type of scene (Goldstein, 2010).

 A study done by Castelhano & Henderson (2008) has shown that color has an influence across a wide variety of scenes and is directly associated with scene gist. Their study shows that removal of color information from normal scenes produced no effect on the activation of a scene gist; however, when structural information was degraded (i.e. the scene was blurred), color had an effect on the activation of a scene gist. We can see that color produced a more pronounced bias effect in blurred scenes. These results suggest that color plays a role in the activation of scene gist but that it is dependent on the quality of structural information (Castlhano & Henderson, 2008). This also supports the finding from Wichmann, Sharpe, & Gegenfurter (2002) study that there are two memory components to the effect of color on memory: structural information and color information.

The ability of color to produce a more pronounced bias effect in blurred scenes shows that it may have acted as a segmenter of scene regions or a direct cue for scene gist (Castelhano & Henderson, 2008). These two functions of color represents two hypothesis respectively – the segmentation hypothesis (color contributes only when the structure is degraded as it helps recover some of the boundary edges that are lost in blurred images; implies that only structure can directly activate scene gist) and the color association hypothesis (color itself is associated with scene gist and can act as a direct cue). Castelhano & Henderson (2008) imply, however, that both the structure and color associated with scene gist can contribute directly to activation.

In a set-up where scenes are presented in a wrong hue, response and recognition was significantly slowed. This shows that the wrong hues could hev potentially cued other scene gists and thus interfere with the activation of the correct scene gist. This suggests that color can act as a continuum in which it can be facilitative or inhibitory depending on how close the colors resemble a matching prototype of a scene (Castelhano & Henderson, 2008). In terms of varying amounts of structure information, man-made scenes are seen as having more unique shapes that are consistently associated with a certain scene type (e.g. beds in bedrooms, counters in kitchens) as compared with natural scenes (e.g. trees can appear in parks, backyards, forests, etc). When these structural information are insufficient, color contributes to the activation of a scene gist.

We have already emphasized that structure information and color information interact for the recognition and memory of scenes. Studies (Wichmann, Sharpe, & Gegenfurtner, 2002; Castelhano & Henderson, 2008) also show the contribution of a third factor – conceptual knowledge. Memory for the details of a briefly presented scene is often “based on the scene’s associated semantic category and is affected by its associated schemas, not the actual details present in the scene” (Brewer & Treyens, 1981; Hollingworth & Henderson, 1999; Intraub, 1981 as cited in Castelhano & Henderson, 2008).

Thus, Paris Hilton, your memory of scenes and the color you associate with these scenes, as well as how you are able to associate various objects to these scenes, is dependent on the interplay of three factors – structure of the scene, color information, and your conceptual prior knowledge of the scene. As with any other perceptual process, you can see that there is a combination of both bottom-up and top-down processes.

I hope that I was able to answer your questions. Cheers to all your future travels!

Senserely yours,

Yana



References

Castelhano, M.S., & Henderson, J.M. (2008). The influence of color on the perception of scene gist. Journal Of Experimental Psychology: Human Perception And Performance, 34(3), 660-675. doi:10.1037/0096-1523.34.3.660

Goldstein, E.B. (2010). Sensation and Perception [Eighth edition]. Canada: Wadsworth, Cengage Learning. 

Wichmann, F.A., Sharpe, L.T., & Gegenfurtner, K.R. (2002). The contributions of color to recognition memory for natural scenes. Journal Of Experimental Psychology: Learning, Memory, And Cognition, 28(3), 509-520. doi:10.1037/0278-7393.28.3.509