The Mechanism Of Prototype Elicitation During Insight Problem Solving

The early Gestalt psychologists claimed that insightful problem solving is resulted from reconstructing the whole problem. The occurrence of the "Aha" experience means rethinking some basic assumptions of the problem content and concluding a new solution, which happens in a relatively unexpected and unpredictable manner (Kohler, 1925;Scheerer,1963).During the last century, Cognitive psychologists had studied the processes of insight regarding to problem solving, using human and animal subjects (e.g.,Kohler,1925;Scheerer,1963;Kaplan & Simon,1990; MacGregor etal.,2001). However, the cognitive mechanism of insight remains largely unknown and there are different theories to explain it.On the basis of previous studies and views, a hypothetical theory about the elicitation of prototypal matters and the quality of heuristic information was put forward recently (Zhang Qinglin,2004). The theory suggested that the insight was a process of prototype elicitation, which was the core component of insight. If the key heuristic information of the prototype was activated appropriately in the brain during the process of insight problem solving, then Insight could occur. This study used this hypothesis to define'Insight'.Here, prototypes were the cognitive events that could facilitate the insight problem solving. It could be the representations of "prototype problems"which were provided by researchers in the experiments.It also could be existing strategies in the mind of participants for the relevant problem solving, or clues which were found by participants in the process of insight problem solving. The activation of prototypal matters could not predicate the happening of insight. Only when the special information embodied in the prototypal matters was noticed by the participants, the insight would happen. The special information was the key heuristic information. The prototypes noticed by the participants or appeared in their mental scope of the solver were named Activation. And the'Elicitation'meant that the key heuristic information of prototypes was used to guide the heuristic searching in the problem space, in order to impel the current insight problems being solved successfully. This theory was more consistent with nature of creative thinking in the reality.Four steps theory for creative problem-solving model was proposed by Wallas(1926). In the Wallas'Stage model, creative insights and illuminations may be explained by a process consisted of 4 stages:(i) Preparation; (ii) Incubation; (iii) Illumination; (iv) Verification. The theory had been widely recognized by other psychologists. However, few researchers had investigated all four stages systematically, while the existing studies focused on behaviors and brain mechanism giving consideration to only one or two stages.Researches of prototype elicitation focused on how the impact of the prototype inspired insight problem solving, rather than stages of its process. Meanwhile, research on insight-the phenomenon of suddenly solving an apparently intransigent problem——has been hampered by limited number of stimulus problems, variety of types, and high level of difficulty. Responding to the need of a larger pool of problems with similar type but varying level of difficulties, we used logogriphs as insight problems. Solving a logogriph requires breaking implicit assumptions of normal reading, which was similar to the restructuring required in insight. We hypothesized that the more implicit assumptions were involved, the more difficult the solution.Based on the "prototype elicitation" theory, this study examined the mechanism of four stages in the process of insight problem solving with different research methods (e.g., behavior, ERP and fMRI),by using traditional Chinese logogriphs. This study was divided into three research stages:The first research stage aimed to examine brain mechanism in the preparatory stage during solving traditional Chinese logogriphs.It contained a total of three experiments:In experiment 1,a two-stage model using a learning-testing experimental paradigm was adopted to examine the neural basis of mental preparation prior to the display of target logogriph, by using event-related functional Magnetic Resonance Imaging (fMRI). Blood oxygenation level-dependent fMRI contrasts between mental preparations of successful insight and routine problem solving were measured. Results showed that mental preparation leading to successful problem solving involved heightened activity in the occipital area, the lingual gyrus and part of the insula. The results indicated that the activation of occipital area might be involved in visual or semantic processing preparation of key heuristic information in prototypal logogriphs; activation of the lingual gyrus and part of the insula might be involve in preparing semantic processing and integration of key information.On the basis of previous experimental paradigm, an online evaluation of the "Aha experience" was added into experiment 2.The Event-Related Potentials (ERP) was used to identify the neural basis of mental preparation. Results showed that the mental preparation for insight logogriphs elicited more positive ERP deflection than routine problem solving respectively in 200-450ms and 450-600ms of the preparatory stage. Dipole analysis located the generators of the first positive component primarily in the precuneus which might be involved in preparing successful prototype retrievals; and the generators of the other positive component primarily in the Posterior Cingulate Gyrus(PCC) and the left middle frontal gyrus.PCC might be involved in attention and non-executive control function, whereas the left middle frontal gyrus might play a role in maintaining information and preparing to understand the potential significations of the coming logogriphs.In experiment 3,a novel three-stage model using a Testing-Learning-Testing experimental paradigm was adopted to examine the neural basis of mental preparation during solving logogriphs with ERP. Preparation 1(prior to the display of relevant stimulates), the mental preparation for Successful logogriphs elicited a more negative ERP deflection than Unsuccessful logogriphs in 1000-1500ms in the preparatory stage. Dipole analysis located the generators of the negative component primarily in the PCC, the medial frontal gyrus and the precuneus. We speculated that PCC and the precuneus regions formed a neural network responsible for the integration of memory and currentinformation processing; the medial frontal gyrus mightbe involved in the subjective mental effort in preparing and deploying attention resources. Preparation 2 (prior to the subjects learning the prototypal logogriphs), mental preparation for Successful logogriphs elicited more negative ERP deflection than Unsuccessful logogriphs respectively in 150-850ms and 950-1500ms of the preparatory stage. Dipole analysis located the generators of the negative component primarily in the Anterior Cingulated Cortex(ACC).The results indicated that the activation of ACC might be related to suppressing extraneous thoughts to focus on the coming logogriphs and preparing to integrate key information with problem information. There was no significant deviation found in the mental preparations between Successful and Unsuccessful logogriphs in Preparation 3.The second research stage aimed to examine the mechanism in the incubation during solving traditional Chinese logogriphs. In experiment 4, we investigated the incubation effect of prototype elicitation in insight problem solving through the'X vs. X(X=8)''Test-Learning-Test' three stages experimental paradigm. The pre-experiments explored the effects of experimental paradigm, incubation time, and experimental materials. Then the formal experiment explored whether the incubation effect was affected by incubation period with the relative positions of prototype learning, different incubation tasks and difficulty of logogriph. The results showed that different incubation effects of prototype elicitation were showed in different times.At the time of 3 seconds, the performance was better in the music group when resolving the difficult logogriph. After learning the prototype by adding incubation period the music group performed significantly better than the other two groups. At the time of 15 seconds, when the incubation period put before the learning the prototype, the performance of music group was obvious promoted. But at this time when the Cognitive Task Group solved medium-difficult puzzle, the incubation showed an inhibitory effect in the'back' position. At the time of 60 seconds, the music group no longer presented incubation effect, whereas an inhibitory effect was found in the interaction of difficulty and location in the Cognitive Task Group.The third research stage aimed to examine brain mechanism in the stages of illumination and verification during solving traditional Chinese logogriphs. We used FOK judgments to divide the problem solving process into several time courses, and then provided feedbacks on answers twice to examine the neural basis of the two stages. We found that the illumination for Successful logogriphs elicited a more negative ERP deflection than Unsuccessful logogriphs in 300-700ms. Dipole analysis located the generators of the negative component primarily in the precuneus and the right precentral gyrus. The results indicated that subjects might have activated heuristic information in prototypal logogriphs before insight occurred, and made connections between old and new information to reconstruct problem representation. In the verification stage, we found that the generators of Feedback Related Negativity (FRN) might be located in ACC. The activation of ACC might reflect the cognitive conflict between expectancy and feedbacks on answers, and the strength was reflected on the amplitude of wave. P300 might reflect the emotional processing of feedback on results, the amplitude of wave might reflect the degree of emotional intensity.