Mean Response Time (ms) Global Data Data as of 2023-10-09 15:59:30 Pacific Daylight Time The plot shows how reaction time varied with the number of distractors. Different lines are for different types of searches and whether the target was present or not. The expected result is that for both feature searches, the reaction time does not vary much as the number of distractors increases. For conjunctive searches both lines should increase with the number of distractors. The conjunctive-absent searches should increase twice as fast as the conjunctive-present searches. Means based on data from 112524 participants. Number of Distractors 4 16 32 64 Feature, Present 745.981 Feature, Absent 810.339 Conjunction, Present 978.290 Conjunction, Absent 1072.672 745.952 810.438 1194.338 1563.688 752.500 820.633 1416.907 2062.743 763.745 824.516 1721.253 2678.893 Standard deviations based on data from 112524 participants. Number of Distractors Feature, Present Feature, Absent Conjunction, Present Conjunction, Absent 4 301.774 342.484 332.815 367.728 628 16 298.948 352.105 379.838 504.452 32 64 299.741 360.145 453.103 677.661 301.375 363.585 586.873 954.327 3000 Feature Present Feature Absent 2500 Conjunction Present 2000 1500 1000 500 Conjunction Absent 8 0 10 20 30 40 50 60 70 Number of Distractors Your summary data Student Information Data Summary for Date Completed Time Spent On Lab Results F23PSYC303L-2 2023-10-06 17:54:03 Pacific Daylight Time 6 minutes The plot shows how reaction time varied with the number of distractors. Different lines are for different types of searches and whether the target was present or not. The expected result is that for both feature searches, the reaction time does not vary much as the number of distractors increases. For conjunctive searches both lines should increase with the number of distractors. The conjunctive-absent searches should increase twice as fast as the conjunctive-present searches. Number of Distractors 4 16 32 64 Feature, Present 759.200 890.600 1032.600 931.000 Feature, Absent Conjunction, Present 1255.400 859.400 1900.400 1135.000 1751.400 1392.000 1791.000 1244.200 Conjunction, Absent 880.600 1594.800 2685.000 3074.000 Mean Response Time (ms) 3500 Feature Present Feature Absent 3000 Conjunction Present Conjunction Absent 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 Number of Distractors Visual Search Debriefing You have successfully submitted this activity. What methods did we employ in this experiment? On each trial, circles and squares of various colors were shown on the screen. Your task was to determine whether or not there was a green circle among the shapes. For the first set of trials (feature search), the other distractor shapes were all blue. For the other set of trials (conjunctive search), some of the other shapes were blue circles and others were green squares. The independent variables in this experiment were (1) the type of search (feature or conjunctive), the number of distractor shapes, and whether the target is present or absent. The dependent variable was the response time between the appearance of the stimuli and your response. What do we predict participants will do? Why? The results are broken down by the type of search and whether the target was present or absent. For feature searches, the response time should not change as the number of distractor shapes increases. This should be true both for when the target is in the frame ("Feature, Present") and for when the target is not in the frame ("Feature, Absent"). For conjunctive searches, the response time should increase as the number of distractor shapes increases. For the conjunctive searches, the rate of increase should be faster when no target is in the frame ("Conjunction, Absent") than when the target is in the frame ("Conjunction, Present"). The pattern of results for the conjunctive searches is consistent with the idea that attentional focus is moved around from shape to shape. Each focus on a shape takes time to judge whether it is the target or not. This explains why search time increases with the number of distractor shapes. If the target is found, the search stops. On the other hand, if the target is not present, you must search all the shapes. This explains why the target-absent trials take longer than the target-present trials. The pattern of results for the feature searches suggests that there is little need for movement of attention from shape to shape. Instead, the properties of the target are able to quickly draw attention to the target (e.g., because it is the only green item). How robust is this effect? Are there limits to this effect? The pattern of results is usually very robust. Mean Response Time (ms) Student Information Data Summary for Date Completed Time Spent On Lab Results F23PSYC303L-2 2023-10-06 17:54:03 Pacific Daylight Time 6 minutes The plot shows how reaction time varied with the number of distractors. Different lines are for different types of searches and whether the target was present or not. The expected result is that for both feature searches, the reaction time does not vary much as the number of distractors increases. For conjunctive searches both lines should increase with the number of distractors. The conjunctive-absent searches should increase twice as fast as the conjunctive-present searches. Number of Distractors 4 16 32 64 3500 Feature Present Feature Absent 3000 Conjunction Present 2500 2000 1500 1000 500 Conjunction Absent Feature, Present 759.200 890.600 1032.600 931.000 Feature, Absent 1255.400 Conjunction, Present 859.400 Conjunction, Absent 880.600 1900.400 1135.000 1594.800 1751.400 1392.000 1791.000 1244.200 2685.000 3074.000 0 10 20 30 40 50 60 70 Number of Distractors Below the figure, state that the figure shows your own results. For feature search, how does the reaction time change as the number of distractors increases? For conjunction search, how does the reaction time change as the number of distractors increases? For conjunction search, does the reaction time for the target-absent condition increase at a faster rate than the target-present condition as the number of distractors increases? Mean Response Time (ms) 3000 Feature Present 2500 Feature Absent Conjunction Present Conjunction Absent 2000 1500 1000 500 B A 0 0 10 20 30 40 50 60 70 Number of Distractors Below the figure, state that the figure shows the global data with the number of participants. For feature search, how does the reaction time change as the number of distractors increases? Explain why. For conjunction search, how does the reaction time change as the number of distractors increases? Explain why. For conjunction search, the reaction time for the target- absent condition increases at a faster rate than the target-present condition as the number of distractors increases. Explain why this happens. Your trial-by-trial data Trial 1 Participant Distractor type Target Number of distractors RT (ms) 234 F23PSYC303L-2 F23PSYC303L-2 Feature Absent 16.0 3830.0 Feature Absent 16.0 2250.0 F23PSYC303L-2 Feature Absent 32.0 2772.0 F23PSYC303L-2 Feature Absent 32.0 3094.0 5 F23PSYC303L-2 Feature Absent 64.0 2536.0 6 F23PSYC303L-2 Feature Present 64.0 1195.0 7 F23PSYC303L-2 Feature Present 64.0 1026.0 8 F23PSYC303L-2 Feature Absent 4.0 1095.0 9 F23PSYC303L-2 Feature Absent 4.0 985.0 10 F23PSYC303L-2 Feature Present 16.0 978.0 11 F23PSYC303L-2 Feature Present 16.0 955.0 12 F23PSYC303L-2 Feature Absent 32.0 1094.0 13 F23PSYC303L-2 Feature Present 64.0 846.0 14 156 F23PSYC303L-2 Feature Present 4.0 924.0 F23PSYC303L-2 Feature Present 32.0 1982.0 F23PSYC303L-2 Feature Absent 16.0 1200.0 17 F23PSYC303L-2 Feature Absent 16.0 1020.0 18 F23PSYC303L-2 Feature Absent 4.0 1123.0 19 21 24 27 28 29 31 22222222202330 F23PSYC303L-2 Feature Absent 64.0 1591.0 F23PSYC303L-2 Feature Absent 32.0 1060.0 F23PSYC303L-2 Feature Absent 64.0 903.0 F23PSYC303L-2 Feature Absent 4.0 1054.0 F23PSYC303L-2 Feature Present 4.0 838.0 F23PSYC303L-2 Feature Present 32.0 874.0 25 F23PSYC303L-2 Feature Absent 16.0 1202.0 26 F23PSYC303L-2 Feature Absent 4.0 2020.0 F23PSYC303L-2 Feature Present 16.0 1269.0 F23PSYC303L-2 Feature Absent 64.0 1706.0 F23PSYC303L-2 Feature Absent 64.0 2219.0 F23PSYC303L-2 Feature Present 32.0 884.0 F23PSYC303L-2 Feature Present 64.0 929.0 F23PSYC303L-2 Feature Present 4.0 714.0 F23PSYC303L-2 Feature Present 4.0 689.0 34 F23PSYC303L-2 Feature Present 32.0 689.0 35 F23PSYC303L-2 Feature Absent 32.0 737.0 36 F23PSYC303L-2 Feature Present 16.0 636.0 37 F23PSYC303L-2 Feature Present 64.0 659.0 38 F23PSYC303L-2 Feature Present 32.0 734.0 39 F23PSYC303L-2 Feature Present 4.0 631.0 40 F23PSYC303L-2 Feature Present 16.0 615.0 41 F23PSYC303L-2 Conjunction Present 64.0 761.0 42 F23PSYC303L-2 Conjunction Absent 32.0 4668.0 43 F23PSYC303L-2 Conjunction Absent 4.0 935.0 44 F23PSYC303L-2 Conjunction Present 16.0 1439.0 45 F23PSYC303L-2 Conjunction Absent 4.0 1088.0 46 F23PSYC303L-2 Conjunction Present 32.0 902.0 47 F23PSYC303L-2 Conjunction Absent 4.0 768.0 48 F23PSYC303L-2 Conjunction Present 32.0 1951.0 49 F23PSYC303L-2 Conjunction Present 4.0 931.0 50 F23PSYC303L-2 Conjunction Absent 64.0 2708.0 51 F23PSYC303L-2 Conjunction Absent 4.0 805.0 52 F23PSYC303L-2 Conjunction Present 32.0 1132.0 53 F23PSYC303L-2 Conjunction Absent 32.0 2197.0 54 F23PSYC303L-2 Conjunction Present 32.0 1116.0 55 F23PSYC303L-2 Conjunction Present 64.0 1193.0 56 F23PSYC303L-2 Conjunction Present 32.0 1859.0 57 F23PSYC303L-2 Conjunction Present 4.0 802.0 58 F23PSYC303L-2 Conjunction Absent 16.0 1782.0 59 F23PSYC303L-2 Conjunction Present 16.0 839.0 60 F23PSYC303L-2 Conjunction Absent 32.0 2379.0 61 F23PSYC303L-2 Conjunction Present 4.0 790.0 62 F23PSYC303L-2 Conjunction Absent 16.0 1493.0 63 F23PSYC303L-2 Conjunction Present 16.0 1369.0 64 F23PSYC303L-2 Conjunction Present 16.0 901.0 65 F23PSYC303L-2 Conjunction Absent 32.0 2081.0 66 F23PSYC303L-2 Conjunction Present 4.0 721.0 67 F23PSYC303L-2 Conjunction Absent 16.0 1537.0 68 F23PSYC303L-2 Conjunction Absent 64.0 4465.0 69 F23PSYC303L-2 Conjunction Absent 64.0 3099.0 70 F23PSYC303L-2 Conjunction Present 4.0 1053.0 71 F23PSYC303L-2 Conjunction Absent 64.0 2173.0 72 F23PSYC303L-2 Conjunction Present 64.0 1470.0 73 F23PSYC303L-2 Conjunction Present 16.0 1127.0 74 F23PSYC303L-2 Conjunction Absent 16.0 1535.0 75 F23PSYC303L-2 Conjunction Absent 32.0 2100.0 76 F23PSYC303L-2 Conjunction Present 64.0 1730.0 77 F23PSYC303L-2 Conjunction Present 64.0 1067.0 78 F23PSYC303L-2 Conjunction Absent 16.0 1627.0 79 F23PSYC303L-2 Conjunction Absent 64.0 2925.0 80 F23PSYC303L-2 Conjunction Absent 4.0 807.0