| Economic decision-making is a process of making choices by weighing gains and losses and their risks,and consists of three stages: choice evaluation,behavioral output,and outcome evaluation.The limited rational decision theory emphasizes that individuals are not fully rational in decision making,and that emotions play a crucial role in decision making.Both trait emotions and state emotions affect decision making,but few studies investigate the brain mechanisms underlying decision making affected by trait emotions.Typical activation by the orbitofrontal cortex(OFC),anterior cingulate,and insula has been considered to be related to decision making and emotion,but the structural basis for the function of these brain regions is unclear.Therefore,this dissertation explores the influence of emotions on decision-making by combining brain structure with decision-related personality traits.Mere brain activation is considered to reflect limited information,and it is important to integrate multimodal neuroimaging methods to explore brain activation and networks at different stages of decision making.In this dissertation,the author employed the classical “Wheel of Fortune Gamble Task”paradigm based on regret theory and disappointment theory,and utilize eye-tracking techniques,structural magnetic resonance imaging(s MRI),diffusion tensor imaging(DTI),and functional Magnetic Resonance Imaging(f MRI),Magnetic Resonance Imaging(MRI),and EventRelated Potential(ERP)to explore the brain mechanisms of emotions influencing economic decision-making behavior in the following five aspects.1.Through eye-tracking and brain structural imaging experiments,voxel-based morphometry(VBM)explored the relationship between gaze patterns,behavioral responses,and gray matter volume(GMV)in the three phases of decision-making,revealed the brain structural basis of disappointment and regret,and the important brain networks involved in decision-making.The gaze time of the selected visual field was significantly higher than that of the unselected visual field,and the gaze time of the selection by individuals was significantly higher than that of selection by machine,which revealed that regret is a different emotion from disappointment.Individuals pay more attention to the amount in the choice phase and more attention to the probability in the outcome phase.VBM analysis revealeded that gray matter volume can predict individual differences in gaze patterns and reaction times,and that the default network,the limbic network,and the frontal-parietal network are important brain network structures related to decision making.2.Brain mechanisms by which regret trait affects the choice stage of decision-making were explored through scale measurements,VBM,task-state f MRI and ERP techniques.Behavioral results revealed that the reaction time of the choose condition was longer than that of the follow condition,and that anticipatory regret,anticipatory disappointment,and maximization of the expected value had a predictive effect on choice behavior.Magnetic resonance results revealed that the orbitofrontal cortex is an important brain structural basis for the regret trait and a key brain region in the selection phase of the mediating regret-influenced economic decision-making task,and that disappointment and regret in decision-making differentially modulate functional connectivity from the orbitofrontal cortex to the inferior frontal gyrus and cerebellum.ERP results indicated that the more difficult the decision-making task was,the higher the level of the maximizing tendency trait was,and the lower the magnitude of the induced N1 component was.3.Using emotion scores to categorize activation in the outcome feedback phase,the study explored brain region activation differences between four emotions(regret,rejoice,disappointment,elation),and brain network participation patterns,revealed that decisionrelated traits affect the activation of the OFC in the outcome phase.When the same amount of money was obtained,emotion scores became lower as the amount of money at the reference point increased,suggesting that individuals’ regret and disappointment emotions were modulated by the experimental design.Differential brain regions for regret and disappointment were mainly the right inferior parietal lobule,and those for rejoice and elation mainly included the right medial superior frontal gyrus,the right inferior frontal gyrus of the insula,and the left superior parietal gyrus.Compared with regret and disappointment,more frontoparietal networks were involved in the differential brain regions of rejoice and elation.Correlation analyses revealed that the stronger the individual’s tendency to seek better choices and the more difficult the degree of decision-making,the lower the intensity of right OFC activation.4.Based on structural and resting brain networks,combined with graph theoretic methods,the role of decision-related OFC in the conversion progression of Alzheimer’s disease was further explored,and it was found that the orbitofrontal cortex plays an important role in the transformation of mild cognitive impairment into Alzheimer’s disease.By exploring the relationship between brain network parameters and individual decisionrelated traits,it was found that the smaller the small-worldness of the structural covariance network,the longer the shortest path length and the greater the tendency to regret.In the resting slow-4 band,the larger the small-worldness of the brain network,the stronger the alternative search ability.Based on the DTI data,the whole-brain connectome prediction model,which mainly contains the connections among the medial frontal network,frontalparietal network,and limbic network,and the connections among the basal ganglia,the parahippocampal gyrus,the caudate nucleus,the cerebellum,can predict the regret tendency and decision difficulty traits.5.The economic decision-making behavior of patients with mild cognitive impairment was measured by the “Wheel of Fortune Gamble Task”paradigm.The results showed that the cognitive level declined with age,and mild cognitive impairment patients had longer reaction time and lower sensitivity to disappointment and regret in decision making.Anticipated regret and maximization of the expected value were predictive of choice behavior in patients with mild cognitive impairment,and anticipated disappointment had no effect on the choice behavior.The outcome scores suggest that mild cognitive impairment patients have an abnormal assessment of emotion rating scales and lack of sensitivity to different levels of disappointment or regret.In this dissertation,author adopt the “Wheel of Fortune Gamble Task”paradigm,using behavioral and scale measures as the core parameters,linking individual neuroimaging indexes and decision-related traits,and exploring the brain mechanisms of emotionaffected decision-making at various phases of the brain,from trait to state,from a single brain region to brain connectivity and brain networks,and from multiple perspectives,from time to space.The dissertation mainly revealed the gaze patterns in the three phases of regret-influenced decision-making,and found that the default network,the limbic network,and the frontoparietal network are the important brain network structures related to decision-making,and the activation differences between different emotions are mainly in the frontoparietal network.The OFC is an important brain structure underlying regret traits and decision-related traits,and is also a key brain region mediating the regret-influenced economic decision-making task.Brain connections and brain networks centered on the OFC play important roles in both emotionally influenced decision making and in the conversion of MCI into Alzheimer’s disease.Compared to traditional computational modeling,neuroimaging perspectives provide new insights for exploring research techniques and methods in the field of economic decision making.For example,eye-tracking provides a new direction for applying regret theory to advertising and marketing,and personality traits such as regret and maximization have different structural and functional bases,which provide important support for the measurement of personality traits in psychology.The imaging results suggest that the OFC can be used as a target for neuromodulation intervention,which provides a new reference for assisting the diagnosis or treatment of cognitive impairment in decision-making. |
PDF Full Text Request