Problem Solving and the Brain. Compound Remote Associate Problems.
Problem Solving and the Brain
Behavioral Studies of Insight• Metcalfe’s experiment (from earlier). – Ss. studied insight problems (e.g. algebra) as well as non-insight problems – At 15 seconds intervals, ss. rated how close they felt to solving the problem – Only for insight problems, ss. suddenly increased warmness ratings before solving problem• Perhaps insight is special? But how do we really know what really happens during insight?
Promise of Brain Imaging Studies• Difficult to link behavioral data to internal processes -- e.g., do warmness ratings really show that insight occurs rapidly?• With brain imaging techniques, we can get converging evidence for a special insight process. Does insight occur suddenly, in the brain, as behavioral data suggests?• Jung-Beeman et al. (2004). Studied neural correlates of “aha” moment using fMRI and EEG
Jung-Beeman et al.• Compound Remote Associate Problems Example: pine, crab, sauce Question: what word can form a familiar compound word or phrase with the each of these words? Solution: apple (pineapple, crabapple, applesauce)
fMRI• Functional Magnetic Resonance Imaging• Measures cerebral blood flow (related to neural activity) in different areas• Results are usually based on the difference in response between experimental and baseline condition MRI scan
Experimental Setup Ss. press button Ss. press button when they solved when they felt a problem insight during problem solvingMeasure brainresponse here
Areas showing greater fMRI signal for insight than non-insight solutionsincreased activity in the right hemisphere anterior Superior Temporal Gyrus
EEG / ERP• EEG: Electroencephalography• Electrodes placed at the scalp; measuring changes in voltage• High temporal resolution, poor spatial resolution – good to measure when processes are initiated as opposed to where
EEG Results Measure high frequency oscillations in gamma band (> 30Hz) For insight problems that were correctly solved, a burst of gamma frequencies 0.3 seconds were observed before the solution response
EEG Results Animation of the last half second (from -0.5 to -0.2) of high- frequency electrical activity at the scalp prior to the button press indicating subjects had solved a problem with insight.from: http://www.psych.nwu.edu/~mjungbee/PLoS_Supp.htm
The Trolley Dilemma• A trolley is running out of control down a track. In its path are 5 people who have been tied to the track by a mad person. Fortunately, you can flip a switch which will lead the trolley down a different track. Unfortunately, there is a single person tied to that track. Should you flip the switch? If you do nothing, the trolley will kill five, but if you intervene it will kill only one. Should you “kill one person” to save five? SWITCH
What justifies your judgment ?• “Save as many as you can.”• “The good of the many outweighs the good of the few.”• “Act so that you provide the maximum benefit to the maximum number of people.”
The footbridge dilemma• similar to trolley dilemma• A runaway trolley threatens to kill five people. You are standing on a footbridge over the tracks, next to a large stranger. If you push the stranger onto the tracks, killing him, his body will prevent the train from reaching the others, saving them. Do you push?
• Most people answer yes to the trolley question, no to the footbridge question• Perhaps what’s wrong with killing the large man to save five is that it would be using the one as a mere means for the benefit of others
Variant of trolley dilemmaAs before, a trolley is hurtlingdown a track towards fivepeople. As in the first case, youcan divert it onto a separatetrack. On this track is a singlelarge man. Without the body ofthis man, the trolley would, ifturned that way, make its way tothe other track and kill the fivepeople.If it wasnt for the presence of thelarge man, flipping the switchwould not save the five. Shouldyou flip the switch? SWITCH
The Surgeon’s DilemmaYou are a surgeon with six patients. Five ofthem need major organ transplants, which youcould easily do if you had access to transplantorgans. The sixth, an ideal donor for all therelevant organs, has a cold. Should you kill oneperson to save five?
• Philosophers have puzzled over why people believe it is morally acceptable to sacrifice one life for five in one case, but unacceptable in the other• Difficult to find a unifying set of principles that explains what is morally acceptable
The psychology of moral reasoning• Prescriptive question: what is right and wrong? Philosophy/Ethics• Descriptive question: what are happens during moral reasoning? psychology – Traditional view (e.g. Kant): moral judgment is primarily a matter of formal reasoning. – Recent insights (Haidt): moral thinking is highly intuitive and emotional, and only appears to be a product of careful reasoning because of people’s after-the-fact rationalizations of their thinking.
• Perhaps the thought of pushing somebody to death is more emotionally salient• Hypothesis (Greene et al.): differences in emotional engagement determine difference in response• Trolley dilemma: “impersonal” moral dilemma.• Footbridge dilemma: “personal” moral dilemma. requires active personal involvement
Recent Brain Imaging Insights• Greene et al.: performed brain imaging experiments to reveal differences in the way the emotional circuits in brain are activated during moral reasoning.
• Trolley dilemma: “impersonal” moral dilemma activated memory areas• Footbridge dilemma: “personal” moral dilemma requires active personal involvement activated brain areas associated with emotion
• Footbridge dilemma activates immediate emotional response• A few subjects still say “appropriate”.• These response times should be slow because the response is “incongruent” with the immediate emotional response
• Results do not show how to reason correctly• They show what happens during reasoning -- intuitive emotional reactions affect moral judgments