Statistical test. Describe the statistical test that was used to test the primary hypothesis in experiment 1. Explain why this analysis is appropriate for testing the hypothesis. (Hint: Consider the design of the study and the nature of the variables.) 570occurs only when a given percept shows sufficient match witha specific internal representation. Indeed, various short- andlong-term processes of episodic memory affect object-identifi-cation time and naming accuracy (e.g., Bentin & McCarthy,1994; Stuss, Picton, Cerri, Leech, & Stethem, 1992; Verfaellie,Gabrieli, Vaidya, Croce, & Reminger, 1996).Following literature suggesting common neural substratesfor memory and perception, we investigated whether inhibi-tory control exerted on memory representations might affectlater perception of suppressed items. In three experiments, weused a modified think/no-think paradigm, in which a percep-tual-identification task replaced the final cued-recall task ofthe original paradigm. We hypothesized that if inhibitorymechanisms exert direct control over perceptual representa-tions, then successful suppression of object memories wouldaccompany impaired subsequent identification of the objects.Experiment IIn our first experiment, we briefly presented object images totest individuals' ability to perceptually identify memory-sup-pressed items.MethodTwenty-five undergraduates with normal or corrected-to-nor-mal vision and normal color perception participated inexchange for course credit. The stimuli were 40 critical and 10filler pairs of a noun and a line drawing of an unrelated famil-iar object (Snodgrass & Vanderwart, 1980). The word anddrawing in each pair were affectively neutral. Among criticalpairs, 10 pairs each were randomly assigned to think and no-think conditions, and the remaining 20 pairs were assigned tothe baseline condition. The design of the experiment consistedof a single factor with three levels (baseline, think, or no-think) that was manipulated within participants. Experiment 1consisted of four phases: pretraining object identification,associative learning, think/no-think training, and posttrainingobject identification.Pretraining object identification. To account for excessiveindividual differences, we first measured participants' abilityto identify briefly presented objects. Twenty line drawings ofobjects different from the critical stimuli were presented indi-vidually for 33 ms each in the center of a screen. Presentationwas preceded by a 400-ms fixation period and followed by a100-ms pattern mask of random line segments. Participantswere asked to write down the names of each object on ananswer sheet. Trials were self-paced.Associative learning. In the associative-learning phase, thetwo items in each stimulus pair were presented concurrentlyfor 5 s. Pairs were presented individually, with a 600-ms inter-stimulus interval between each presentation. Participants wereinstructed to memorize each association for a later memorytest. After the initial learning cycle, participants were asked toKim, Yirecall corresponding target objects when probed with cuewords. The learning phase was repeated up to four times untilcued-recall accuracy reached 50% at minimum.Think/no-think training. Each trial of think/no-think trainingconsisted of a 200-ms fixation cross (either green or red) and a4-s cue word. In the think condition (indicated by a green fixa-tion cross), participants were instructed to think of the targetdrawing when the cue word appeared. In the no-think condi-tion (indicated by a red fixation cross) participants wereinstructed not to think of the target drawing when the cue wordappeared, thus preventing it from entering their consciousness.Twenty cue words (10 each for the think and no-think condi-tions) were presented 12 times in random order. Trials wereseparated by 400-ms intertrial intervals. Cue words assignedto the baseline condition were not presented during thetraining.Posttraining object identification. The procedure for post-training object identification was identical to the procedure forthe pretraining phase except that 40 critical target drawingswere presented individually either on the left or the right sideof a screen. The location and order of presentation were ran-domly determined.Results and discussionData from 5 participants whose identification performanceduring pretraining was excessively low (accuracy ≤ 10%)were excluded from the main analysis, which left data from 20participants for the analysis. The percentage of correctly iden-tified objects in posttraining in the three conditions was sub-mitted to a one-way repeated measures analysis of variance(ANOVA). The effect of condition was significant, F(2, 38)3.35, MSE = 164.45, p = .046, n₂² = .15 (Fig. 1). Participantsidentified significantly fewer objects in the no-think condition(M = 35%) than in the baseline condition (M= 42.8%), t(19) =2.55, p = .02, d = 0.85. In contrast, no significant differencewas observed between the percentage of objects identified inthe think condition (M = 45%) and in the baseline condition,p.5. These results indicate that suppressing memories ofvisual objects impairs subsequent identification of thoseobjects when they are briefly presented.Experiment 2To generalize the results of Experiment 1, we presented noise-occluded images in the object-identification phase and com-pared the amounts of information required for correctidentification between conditions.MethodTwenty-six undergraduates with normal or corrected-to-normal vision and normal color perception participated forcourse credit. In this experiment, we used the same stimuli and

Question

Statistical test. Describe the statistical test that was used to test the primary hypothesis in experiment 1. Explain why this analysis is appropriate for testing the hypothesis. (Hint: Consider the design of the study and the nature of the variables.) 570occurs only when a given percept shows sufficient match witha specific internal representation. Indeed, various short- andlong-term processes of episodic memory affect object-identifi-cation time and naming accuracy (e.g., Bentin & McCarthy,1994; Stuss, Picton, Cerri, Leech, & Stethem, 1992; Verfaellie,Gabrieli, Vaidya, Croce, & Reminger, 1996).Following literature suggesting common neural substratesfor memory and perception, we investigated whether inhibi-tory control exerted on memory representations might affectlater perception of suppressed items. In three experiments, weused a modified think/no-think paradigm, in which a percep-tual-identification task replaced the final cued-recall task ofthe original paradigm. We hypothesized that if inhibitorymechanisms exert direct control over perceptual representa-tions, then successful suppression of object memories wouldaccompany impaired subsequent identification of the objects.Experiment IIn our first experiment, we briefly presented object images totest individuals' ability to perceptually identify memory-sup-pressed items.MethodTwenty-five undergraduates with normal or corrected-to-nor-mal vision and normal color perception participated inexchange for course credit. The stimuli were 40 critical and 10filler pairs of a noun and a line drawing of an unrelated famil-iar object (Snodgrass & Vanderwart, 1980). The word anddrawing in each pair were affectively neutral. Among criticalpairs, 10 pairs each were randomly assigned to think and no-think conditions, and the remaining 20 pairs were assigned tothe baseline condition. The design of the experiment consistedof a single factor with three levels (baseline, think, or no-think) that was manipulated within participants. Experiment 1consisted of four phases: pretraining object identification,associative learning, think/no-think training, and posttrainingobject identification.Pretraining object identification. To account for excessiveindividual differences, we first measured participants' abilityto identify briefly presented objects. Twenty line drawings ofobjects different from the critical stimuli were presented indi-vidually for 33 ms each in the center of a screen. Presentationwas preceded by a 400-ms fixation period and followed by a100-ms pattern mask of random line segments. Participantswere asked to write down the names of each object on ananswer sheet. Trials were self-paced.Associative learning. In the associative-learning phase, thetwo items in each stimulus pair were presented concurrentlyfor 5 s. Pairs were presented individually, with a 600-ms inter-stimulus interval between each presentation. Participants wereinstructed to memorize each association for a later memorytest. After the initial learning cycle, participants were asked toKim, Yirecall corresponding target objects when probed with cuewords. The learning phase was repeated up to four times untilcued-recall accuracy reached 50% at minimum.Think/no-think training. Each trial of think/no-think trainingconsisted of a 200-ms fixation cross (either green or red) and a4-s cue word. In the think condition (indicated by a green fixa-tion cross), participants were instructed to think of the targetdrawing when the cue word appeared. In the no-think condi-tion (indicated by a red fixation cross) participants wereinstructed not to think of the target drawing when the cue wordappeared, thus preventing it from entering their consciousness.Twenty cue words (10 each for the think and no-think condi-tions) were presented 12 times in random order. Trials wereseparated by 400-ms intertrial intervals. Cue words assignedto the baseline condition were not presented during thetraining.Posttraining object identification. The procedure for post-training object identification was identical to the procedure forthe pretraining phase except that 40 critical target drawingswere presented individually either on the left or the right sideof a screen. The location and order of presentation were ran-domly determined.Results and discussionData from 5 participants whose identification performanceduring pretraining was excessively low (accuracy ≤ 10%)were excluded from the main analysis, which left data from 20participants for the analysis. The percentage of correctly iden-tified objects in posttraining in the three conditions was sub-mitted to a one-way repeated measures analysis of variance(ANOVA). The effect of condition was significant, F(2, 38)3.35, MSE = 164.45, p = .046, n₂² = .15 (Fig. 1). Participantsidentified significantly fewer objects in the no-think condition(M = 35%) than in the baseline condition (M= 42.8%), t(19) =2.55, p = .02, d = 0.85. In contrast, no significant differencewas observed between the percentage of objects identified inthe think condition (M = 45%) and in the baseline condition,p>.5. These results indicate that suppressing memories ofvisual objects impairs subsequent identification of thoseobjects when they are briefly presented.Experiment 2To generalize the results of Experiment 1, we presented noise-occluded images in the object-identification phase and com-pared the amounts of information required for correctidentification between conditions.MethodTwenty-six undergraduates with normal or corrected-to-normal vision and normal color perception participated forcourse credit. In this experiment, we used the same stimuli and

Accepted Answer

When it comes to psychology, the scientific method of research is often used in order to uncover and…