Memory for Color in Familiar vs. Non-familiar Images Presented by: Megan Guenin

Prior Research Cycowicz & Friedman (2003); Source memory for the color of pictures: Event-related brain potentials (ERPs) reveal sensory-specific retrieval- related activity. Cycowicz & Friedman (2003); Source memory for the color of pictures: Event-related brain potentials (ERPs) reveal sensory-specific retrieval- related activity. Wanted to see if episodic memory (EM) effects stemmed from differences in task paradigms or from source-attributed differences. Wanted to see if episodic memory (EM) effects stemmed from differences in task paradigms or from source-attributed differences.

Prior Research Cont.; Cycowicz & Friedman Study block; viewed images outlined in either green or red Study block; viewed images outlined in either green or red Participants asked to memorize both picture and color Participants asked to memorize both picture and color Sequential Task: Judge whether old or new; if old what color? Sequential Task: Judge whether old or new; if old what color? Exclusion Task: Red or Green defined as target; asked if picture had been seen in target color or non-target color (did not have to determine if image was seen before). Exclusion Task: Red or Green defined as target; asked if picture had been seen in target color or non-target color (did not have to determine if image was seen before).

Prior Research Cont.; Cycowicz & Friedman Results: For both tasks, late, parietao-occipital EM effects observed. Results: For both tasks, late, parietao-occipital EM effects observed. Provides evidence that memories for perceptual attributes such as color are stored in and retrieved from sensory- specific cortical areas. Provides evidence that memories for perceptual attributes such as color are stored in and retrieved from sensory- specific cortical areas.

My Study Extension of group project; Contextual Influence on Familiar vs. Non-familiar Images Extension of group project; Contextual Influence on Familiar vs. Non-familiar Images Present study looks at different kind of context change; seeing an image in color vs. in black and white Present study looks at different kind of context change; seeing an image in color vs. in black and white Does the brain react differently to familiar images (i.e. photographs) when seen in a different color context? Will the brain also have a reaction to unfamiliar images (i.e. fractals) when seen in the different color context? Does the brain react differently to familiar images (i.e. photographs) when seen in a different color context? Will the brain also have a reaction to unfamiliar images (i.e. fractals) when seen in the different color context?

Hypothesis Viewing the second presentation of an image in a changed color context will elicit a different neurological response than if the color context does not change. Viewing the second presentation of an image in a changed color context will elicit a different neurological response than if the color context does not change. This response may be more predominant with fractal images because their ambiguity leaves us with little to remember them by besides color. This response may be more predominant with fractal images because their ambiguity leaves us with little to remember them by besides color.

Methods Participant Participant 21 year old male student, personally recruited 21 year old male student, personally recruited Stimuli and Materials Stimuli and Materials Two types of images used; 200 photographs of people and things, and 200 fractals. Two types of images used; 200 photographs of people and things, and 200 fractals. The photographs were obtained through internet and an image database, fractals found through internet. The photographs were obtained through internet and an image database, fractals found through internet. Stimuli were shown on computer screen in Tom Busey’s EEG laboratory Stimuli were shown on computer screen in Tom Busey’s EEG laboratory EEG cap, provided by lab EEG cap, provided by lab

Stimuli

Methods cont. Design and Procedure Design and Procedure Took half the picture images (100) and half the fractal images (100) and converted them into black and white. Took half the picture images (100) and half the fractal images (100) and converted them into black and white. Categorized images into 4 conditions Categorized images into 4 conditions 1. Color to Color Pictures 2. Black and White to Color Pictures 3. Color to Color Fractals 4. Black and White to Color Fractals

Methods cont. Images shown in a study trial, then a test trial. EEG did not record study trial. Images shown in a study trial, then a test trial. EEG did not record study trial. In study trial, participant shown color images and black and white images. In study trial, participant shown color images and black and white images. In test trial, participant shown only color images. In test trial, participant shown only color images. Randomized order between picture images and fractal images Randomized order between picture images and fractal images In Faraday cage, subject wore EEG cap while viewing images, shown for 1 second each In Faraday cage, subject wore EEG cap while viewing images, shown for 1 second each

Results of all Conditions

All conditions at P08

All Conditions at P8

Black and White to Color Conditions at P8

Spatial Plots for Pictures and Fractals Black and White to Color PicsColor to Color Pics Black and White to Color Fractals Color to Color Fractals

Black and White to Color PicturesBlack and White to Color Fractals Spatial Plots of Color Change in Picture and Fractal Conditions

Discussion Results show little difference in neurological activity between the two picture conditions. Results show little difference in neurological activity between the two picture conditions. Seeing the second presentation of a picture in a different color context elicited about the same neurological responses as seeing the picture in the same color context. Seeing the second presentation of a picture in a different color context elicited about the same neurological responses as seeing the picture in the same color context. However, there was a different neurological response between the picture conditions and the fractal conditions. However, there was a different neurological response between the picture conditions and the fractal conditions.

Discussion Cont.

Furthermore, there was a difference in neural activity between the two fractal conditions. Furthermore, there was a difference in neural activity between the two fractal conditions. This provides evidence that supports my idea that the color change in the fractal conditions would create a difference in neural activity due to their ambiguity. This provides evidence that supports my idea that the color change in the fractal conditions would create a difference in neural activity due to their ambiguity.

Possible Reasons for these Outcomes Simple design; subject not required to do anything in addition to looking at images. Simple design; subject not required to do anything in addition to looking at images. Wanted to see if brain would recognize images again; perhaps asking subject to perform an actual memory task would provide different results for the picture condition. Wanted to see if brain would recognize images again; perhaps asking subject to perform an actual memory task would provide different results for the picture condition. Also, perhaps fractals not so unfamiliar to this particular subject… Also, perhaps fractals not so unfamiliar to this particular subject…

Questions or Comments?