Memory for Color Memory for Color in Familiar vs. Non-in Familiar vs. Non-

familiar Imagesfamiliar Images

Presented by:Presented by:

Megan GueninMegan Guenin

Prior ResearchPrior Research

Cycowicz & Friedman (2003); Cycowicz & Friedman (2003); Source memory for the color of Source memory for the color of pictures: Event-related brain pictures: Event-related brain potentials (ERPs) reveal sensory-potentials (ERPs) reveal sensory-specific retrieval-related activity.specific retrieval-related activity.

Wanted to see if episodic memory Wanted to see if episodic memory (EM) effects stemmed from (EM) effects stemmed from differences in task paradigms or differences in task paradigms or from source-attributed differences.from source-attributed differences.

Prior Research Cont.; Cycowicz & Prior Research Cont.; Cycowicz & FriedmanFriedman

Study blockStudy block; viewed ; viewed images outlined in either images outlined in either green or redgreen or red

Participants asked to Participants asked to memorize both picture and memorize both picture and colorcolor

Sequential TaskSequential Task: Judge : Judge whether old or new; if old whether old or new; if old what color?what color?

Exclusion TaskExclusion Task: Red or : Red or Green defined as target; Green defined as target; asked if picture had been asked if picture had been seen in target color or non-seen in target color or non-target color (did not have target color (did not have to determine if image was to determine if image was seen before). seen before).

Prior Research Cont.; Cycowicz & Prior Research Cont.; Cycowicz & FriedmanFriedman

ResultsResults: For both : For both tasks, late, parietao-tasks, late, parietao-occipital EM effects occipital EM effects observed.observed.

Provides evidence Provides evidence that memories for that memories for perceptual attributes perceptual attributes such as color are such as color are stored in and stored in and retrieved from retrieved from sensory-specific sensory-specific cortical areas.cortical areas.

My StudyMy Study Extension of group project; Extension of group project; Contextual Contextual

Influence on Familiar vs. Non-familiar Influence on Familiar vs. Non-familiar ImagesImages

Present study looks at different kind of Present study looks at different kind of context change; seeing an image in color vs. context change; seeing an image in color vs. in black and whitein black and white

Does the brain react differently to familiar Does the brain react differently to familiar images (i.e. photographs) when seen in a images (i.e. photographs) when seen in a different color context? Will the brain also different color context? Will the brain also have a reaction to unfamiliar images (i.e. have a reaction to unfamiliar images (i.e. fractals) when seen in the different color fractals) when seen in the different color context?context?

HypothesisHypothesis

Viewing the second presentation of an Viewing the second presentation of an image in a changed color context will image in a changed color context will elicit a different neurological response elicit a different neurological response than if the color context does not than if the color context does not change.change.

This response may be more This response may be more predominant with fractal images predominant with fractal images because their ambiguity leaves us with because their ambiguity leaves us with little to remember them by little to remember them by besidesbesides color. color.

MethodsMethods ParticipantParticipant

21 year old male student, personally recruited21 year old male student, personally recruited Stimuli and MaterialsStimuli and Materials

Two types of images used; 200 photographs of Two types of images used; 200 photographs of people and things, and 200 fractals.people and things, and 200 fractals.

The photographs were obtained through The photographs were obtained through internet and an image database, fractals found internet and an image database, fractals found through internet.through internet.

Stimuli were shown on computer screen in Stimuli were shown on computer screen in Tom Busey’s EEG laboratoryTom Busey’s EEG laboratory

EEG cap, provided by labEEG cap, provided by lab

StimuliStimuli

Methods cont.Methods cont.

Design and ProcedureDesign and Procedure Took half the picture images (100) and Took half the picture images (100) and

half the fractal images (100) and half the fractal images (100) and converted them into black and white.converted them into black and white.

Categorized images into 4 conditions Categorized images into 4 conditions 1. Color to Color Pictures1. Color to Color Pictures

2. Black and White to Color Pictures2. Black and White to Color Pictures

3. Color to Color Fractals3. Color to Color Fractals

4. Black and White to Color Fractals4. Black and White to Color Fractals

Methods cont.Methods cont.

Images shown in a study trial, then a test Images shown in a study trial, then a test trial. EEG did not record study trial.trial. EEG did not record study trial.

In study trial, participant shown color In study trial, participant shown color images and black and white images.images and black and white images.

In test trial, participant shown only color In test trial, participant shown only color images.images.

Randomized order between picture images Randomized order between picture images and fractal imagesand fractal images

In Faraday cage, subject wore EEG cap while In Faraday cage, subject wore EEG cap while viewing images, shown for 1 second eachviewing images, shown for 1 second each

Results of all ConditionsResults of all Conditions

All conditions at P08All conditions at P08

All Conditions at P8All Conditions at P8

Black and White to Color Black and White to Color Conditions at P8Conditions at P8

Spatial Plots for Pictures and FractalsSpatial Plots for Pictures and Fractals

Black and White to Color Pics Color to Color Pics

Black and White to Color Fractals Color to Color Fractals

Black and White to Color Pictures Black and White to Color Fractals

Spatial Plots of Color Change in Spatial Plots of Color Change in Picture and Fractal ConditionsPicture and Fractal Conditions

DiscussionDiscussion

Results show little difference in Results show little difference in neurological activity between the two neurological activity between the two picture conditions.picture conditions. Seeing the second presentation of a picture in Seeing the second presentation of a picture in

a different color context elicited about the a different color context elicited about the same neurological responses as seeing the same neurological responses as seeing the picture in the same color context.picture in the same color context.

However, there was a different However, there was a different neurological response between the picture neurological response between the picture conditions and the fractal conditions.conditions and the fractal conditions.

Discussion Cont.Discussion Cont.

Discussion Cont.Discussion Cont. Furthermore, there Furthermore, there

was a difference in was a difference in neural activity neural activity between the two between the two fractal conditions.fractal conditions.

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

Possible Reasons for these Possible Reasons for these OutcomesOutcomes

Simple design; subject not required to do Simple design; subject not required to do anything in addition to looking at anything in addition to looking at images.images.

Wanted to see if brain would recognize Wanted to see if brain would recognize images again; perhaps asking subject to images again; perhaps asking subject to perform an actual memory task would perform an actual memory task would provide different results for the picture provide different results for the picture condition.condition.

Also, perhaps fractals not so unfamiliar Also, perhaps fractals not so unfamiliar to this particular subject…to this particular subject…

Questions or Comments?Questions or Comments?