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Scientists from Harvard University believe that the human thought process can be sub-divided into two different modes — verbal and visual. Say, for example, when you imagine a dream about your next vacation where you are sitting under a tree, you are probably re-creating the illustration that rejoices you.
On the contrary, when you think about a presentation at work, you are probably thinking between words and sentences. While the former example creates a sense of illustration, the latter gives rise to an inner speech. Social cognition is something that aids in understanding how we interpret the events happening around us. This is the reason why different people draw different conclusions regarding the same event.
We may feel happy for a moment while at the other moment, we may feel extremely sad or embarrassed. While affect helps us understand things that are either going right or wrong, mood helps us understand both positive and negative feelings. Brief but often intense, emotions deal with your mental and physiological well-being. Actions, behaviour, and cognition are the three fundamental pillars of the human thought process.
Rather than running separately, they blend with each other, enabling us to perceive the world around us, listen to our conscious and subconscious desires, and respond accordingly.
Thus, humans can be regarded as active consumers of all the sensory impressions. Social rewards for sharing goods, services, and emotions include a wide array of benefits such as praise, attention, financial support, and love. Advances such as wearable sensor technologies and multi-modal data acquisition and analysis protocol have been backing researchers worldwide to unveil the secrets of the human thought process.
A distinction is made according to the psychology of thinking in the dual process theory of thought between fast, effortless associative processes and slow, deliberative ones Kahneman, This theory has been exploited both theoretically, to better understand human thought, and in many applications of behavior modification Thaler and Sunstein, This paper proposes that an amalgamation of the aspects of these two topics could be of mutual benefit to scientists within the respective fields.
The discovery of the DMN has stimulated several hypotheses regarding the neural basis of the self and the theory of the mind. However, with few exceptions, these hypotheses lack reference to current research on thought processes like reasoning and decision-making. A role of the DMN in the organization and expression of preplanned, reflexive behaviors characteristics of fast thinking has been mentioned by Raichle More recently, the contribution of the DMN to automated processing has been also suggested Vatansever et al.
In contrast, the dual process theory of thought is the most shared explanation of how thoughts arise but does not adequately address the neural basis of thought, although an attempt has been made to determine the relationship between ego depletion and biological parameters Elkins-Brown et al.
Thus, in our opinion the DMN may provide a neural foundation for the associative, fast, and effortless form of thinking elucidated by the dual process theory. Since the earliest days of philosophical enquiries into the mind, many researchers have entertained the idea that two different systems of thought co-exist; a quick, automatic, associative, and affective-based form of reasoning and a slow, thoughtful, deliberative process Sloman, , ; Epstein and Pacini, ; Lieberman, ; Stanovich, ; Kahneman and Frederick, ; Evans, The differences are reflected by the terminology.
For example, the two co-existing processes have variously been dubbed System 1 vs. System 2 Stanovich, , ; Kahneman and Frederick, , intuition vs. Broadly speaking, fast thinking is quick, effortless, associative and experience-based, and, according to some authors e.
By contrast, slow thinking requires effort and the use of cognitive resources, and is based on symbolic and abstract rule manipulation. According to Evans there are two ways in which the two processes might interact. Parallel models Denes-Raj and Epstein, ; Sloman, suggest that fast and slow thinking occur simultaneously and thus there is a continuous monitoring and feelings of conflict. In contrast, Default-Interventionist DI models De Neys and Glumicic, ; Evans and Stanovich, claim that fast thinking generates intuitive default responses in which subsequent slow thinking processing may or may not serially intervene provided that adequate resources are available.
Sloman points out that the distinction between the two cannot be explained as a simple discrepancy between conscious and unconscious processes, or between rational and irrational processes. Indeed, it is possible through introspection to be conscious of either form of thinking.
The difference is that one can have conscious awareness of the various processing steps involving in slow thinking, but only the output of the fast thinking reasoning process. In addition, either thinking modality can lead to rational or irrational conclusions being drawn.
In particular, with fast thinking, sophisticated causal reasoning conclusions can be formed, based on normative principles Sloman, Thus, inhibition by slow thinking is unnecessary. Slow thinking requires mental effort as measured by biological indices, such as pupil dilation Kahneman and Beatty, ; Kahneman, Typically, mental effort is required for tasks requiring attention.
However, a recent meta-analysis Carter et al. The current debate seems to support a domain-specific conception of the ego depletion effect that is strongly affected by individual differences Dang et al. The idea of DMN has its roots in the neuroimaging research revealing task-induced activity decreases from a resting state in a set of brain regions that were characterized for the first time by Shulman et al.
These observations, along with findings reporting high metabolic activity in these regions at rest Raichle et al. Subsequent studies demonstrated that the main nodes of the DMN are functionally and structurally connected Greicius et al. The brain regions involved in the DMN include the medial prefrontal cortex, the posterior cingulate cortex, the inferior parietal lobule, the lateral temporal cortex, the dorsal medial prefrontal cortex, and the hippocampal formation Buckner et al.
The DMN is characterized by lower activity levels during goal-directed cognition or when a person is engaged in a particular task requiring externally directed attention, and higher activity levels when awake and involved in mental processes requiring low attentional demands. Given the association between the DMN and states in which thought is focused on internal channels, the DMN is generally considered the neural basis of spontaneous cognition Buckner et al.
Spontaneous cognition is receiving increased attention, motivating researchers to renew previous routes of investigation and introduce novel methods and experimental paradigms Smallwood and Schooler, An example of such an experimental paradigm involves the idea of stimulus-independent thoughts SITs , which are defined Buckner et al. SITs have been researched since the s, albeit under a different classification Antrobus, However, interest in this topic has increased, which, after the dissemination of the DMN concept, led to exploration of the relationship between neural activity and SITs McKiernan et al.
Two main hypotheses have been proposed to explain DMN function; the internal mentation hypothesis and the sentinel hypothesis Buckner et al.
According to the former, the DMN plays a role in self-referential processes, i. By contrast, the sentinel hypothesis claims that the DMN helps to monitor the external environment i.
Very recently, the role of the DMN was highlighted in automatic behavior the rapid selection of a response to a specific and predictable context Vatansever et al. A few recent papers have begun to connect the two distinct subfields sketched above, from both a theoretical Raichle, and empirical perspective Vatansever et al. Indeed, several potential similarities exist between the dual-process theory of thought and the DMN, as illustrated in this paper.
Similarly, the cognitive resources available to monitor the environment the sentinel hypothesis parallel those available in a state of cognitive ease and are reduced in conditions under which the ego is depleted dual process theory. Beyond these general similarities, recent findings by Vatansever et al. PARCS theory may play a seminal role in integrating these two subfields since it integrates a dual-process view similar to that of dual process theory of thought Carver et al.
Moreover, PARCS theory is also able to explain the specific contexts in which the ego depletion effect holds in a way that is compatible with dual process theories Tops, However, there is also evidence of incongruent features and a lack of correlation between the two theories—for example, the absence of a clear link between autobiographical memory or envisioning the future and fast thinking. Given that the few works have been published on the subject and the potential similarities between DMN and dual process theories of thought, we advocate a deeper and more systematic investigation of the several parallelisms and limitations between the two ideas.
DMN function could be better identified using the well-structured corpus of the dual-process theory of thought, while the DMN could constitute a potential neural basis for use in the dual process theory, thus creating a bridge between the psychology of thinking and neuroscience.
GG and FG equally contributed to all phases of the development of the manuscript including conception, literature review, and writing. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Antrobus, J. Information theory and stimulus independent thought.
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