This was originally written for Washington State University’s PSYCH-384 Course under Alexandra Stubblefield.
A poison dart frog ascends a tree, carrying a young tadpole on its back. A young artist rushes, nearly late for class, navigates dingy and squealing subways, seas of yellow cabs flowing through streets, and rivers of humanity hyper focused on reaching their destinations across sidewalks through Manhattan. A carpenter places stock between a spindle and tailstock quill on a lathe, turning to activate the machine, and readies a tool to realize a perceived design. When thinking back to the phenomenological experiences of daily activities, for example, when putting one’s shoes on, where is the sense of “self”? Does one think, “now I will move the left finger to the right to touch and sense the texture, to grab the thread?” Most likely not. What is revealed in such a hypothetical situation is that while “I will” was momentarily communicated, sensory-motor activity is oft in flight, sans notions of self. This reality is highly experienced in sports, art, analysis, and many activities where increasing skill meets up with increasing challenge—the foundation of what Mihaly Csikszentmihalyi, had called “flow”.
Csikszentmihalyi’s main research area of forty years explored “cultural evolution, play, and adolescent development” (Csikszentmihalyi, 2014a, p. ix). His early life, he had been driven through experience of World War II, to find a “radical” remedy for the “systemic fault in the human condition” (p. xiii). The main body of Csikszentmihalyi’s work focused on “psychic energy, or attention” (p. xv). This work explored enjoyment and creativity beyond the work of prior psychological theorists, and it was this work that resulted in two days of conversation with Martin Seligman after a chance encounter in Kona Village, Hawaii in the 1990s (Claremont Graduate University, 2021). The results of this meeting are sensed Seligman’s 1998 APA Presidential address, that positive psychology is “a reoriented science that emphasizes the understanding and building of the most positive qualities of an individual: optimism, courage, work ethic, future-mindedness, interpersonal skill, the capacity for pleasure and insight, and social responsibility” (APA, 2008). Today, Csikszentmihalyi’s findings on human capacity for flow have been called “the secret to happiness” and it is backed by both qualitative and quantitative analysis. Yet, while qualitative and quantitative self-reports are one thing, neuroscience is another—what is flow within perception, and more so, what is operating at a neurophysiological level that “creates” it?
What is Flow?
To be blunt, flow is defined as optimal experience (Csikszentmihalyi, 2014c, p. 212), which is associated with optimizing experiences of goal directed behavior that produces positive affect (Csikszentmihalyi, 2014d, p. 206). Yet Csikszentmihalyi’s studies examined not generalized goals like completing a college degree, but examined right down into the weeds of experience, in flight, solving challenges, even right down to making coffee, or washing a spoon. In terms of positive psychology, ordered information flow (i.e., sensory perceptions) leads an ordered consciousness, where ordered consciousness is associated with optimal experience—the “‘bottom line’ of existence” (Csikszentmihalyi, 2014c, p. 209-211). Csikszentmihalyi’s research defines flow as the optimal experience of opportunity and ability from the perspective of a researcher, and anxiety and boredom from an experience perspective (Csikszentmihalyi, 2014c, p. 212). Flow is correlated to a dimension of comfortable pleasure to strenuous enjoyment (Csikszentmihalyi, 2014c, p. 230). Yet, while clearly relatable, a paradoxical finding had found that those “in flow” lack perception of self (Csikszentmihalyi, 2014b, p. 141; Csikszentmihalyi & Nakamura, 2014, pp. 221-223). Flow was discovered to nourish self, but self “destroys enjoyment” (p. 223). Csikszentmihalyi offers an Occam’s explanation:
Only when actions depart from expectations, when unlikely intentions are fulfilled, does an “I” become justified as an explanatory construct. In subjective experience at least, the free self becomes a reality when action bears witness to its existence… After successfully coping with unlikely challenges, the “I” might reappear in consciousness as the “me.” But it is a different “me” from what it had been before; it is now stronger and more competent (Smith, 1968, 1978; White 1959). (Csikszentmihalyi, 2014b, p. 223; citations preserved)
Paradox oft is a result of unexamined assumptions (a play on Goldratt’s theory of constraints), and it is these that concealing additional relationships. As to examination, Seligman & Csikszentmihalyi (2000) challenged the field to explore the “neurochemistry and anatomy of flow” (p. 12). Positive psychology research is awash in numerous studies, and many more continue to date, yet it may be worth taking up the challenge to execute a literature review of the neurophysiology of the paradox of flow and self-concept (herein the self-enjoyment paradox [SEP]) and offer an assessment of future applications.
It is worth reviewing neurophysiological aspects of the components of the SEP of self-nourishment (identity nourishment [i.e., nutriment]) and self-induced-enjoyment-destruction (i.e., suffering). There is ongoing extensive research in self-concept perception as it relates to psychology and neurology. Yet, as flow is a relatively new concept, there is less neurophysiological research into perceptive “ordered information flow”. That said, within the constraints of SEP, the evidence that flow is absent self-concept, whereas the recollection of self-concept destroys flow, leads a researcher to investigate neuro-intercorrelates of self-concept and flow. It is difficult to execute a literature review on SEP itself, due to a lack of research in this area, however one may investigate how and where self-concept and flow interact, or rather, how self-concept and flow moderate each other, if there is moderation at all, or if there are iterations of moderation occurring where select permutations demonstrate selectivity? In the pursuit of “ordered information flow” (it’s happening in the construction of this literature review), four categories around the topic of main concern will be sampled from literature, 1) neurophysiology of self-reference (i.e., self-concept), 2) neurophysiology of flow, 3) flow associated neurophysiology, and 4) an analysis of SEP and neurophysiology. In final discussion, some observations, research questions, and implications will be considered.
Neurophysiology of Self-Reference
First, as it is evidenced that self-concept is paradoxically absent in flow (Csikszentmihalyi, 2014b, pp. 141-142), it is valuable to review existing literature regarding neurocorrelates of self-concept as an activity of self-referencing. The depths to which one processes information yields stronger recall (i.e., memory), this is known as the depth of processing (DOP; Craik & Lockhart, 1972). Self-reference yields strong DOP, demonstrating enhanced recall, otherwise known as the self-reference effect (SRE; Higgins & Bargh, 1987; Symons & Johnson, 1997). SRE has roots in research on “self-reference as an encoding device” (Rogers et al., 1977, p. 679). SRE had been studied with clever experiments using response-time tests to adjectives etc., to explore research questions.
Numerous researchers have demonstrated that the cortical midline structures (CMSs) of the medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), and posteromedial cortices (PMCs) are central to self-reference (Christoff et al., 2009; Kelley et al., 2002, Moran et al., 2006; Northoff et al., 2006; Schmitz et al., 2004). Compelling research from Philippi et al. (2012) had discovered that those with lesions in the mPFC had destroyed SRE. A later study by Dégeilh et al. (2015) found that the rostral anterior cingulate cortex (rACC) plays central role to adolescent self-reference.
There is research that attempts to resolve some doubt as to the function of the mPFC, ACC, and PMCs. Araujo et al. (2013) attempted to differentiate self-referencing by employing meta-analysis of self-traits and other-traits using response-time tests across 28 publications and 31 studies with different participants (pp. 1-2). Araujo et al.’s findings found that while self-traits activated the mPFC, other-traits activated the mPFC as well, though to a lesser degree (p. 7). In Amodio & Frith’s (2006) review of literature, it is proposed that ventral mPFC is activated in self-referencing, and dorsal mPFC is activated for other[-referencing]. That said, considering the extensive results and meta-analysis, including Araujo’s findings, the mPFC, ACC, and PMCs are evidenced neurocorrelates of self-referencing, and this is sufficient for the purpose of investigating SEP. In this regard, mPFC, ACC, and PMCs activation is expected to be attenuated during flow.
Neurophysiology of Flow
Early flow research relied on self-reports, namely the experience sampling method (ESM) (Larson & Csikszentmihalyi, 2014; Csikszentmihalyi, 2014c). These self-reports are valuable in providing both qualitative and quantitative data (Csikszentmihalyi & Larson, 2014), where its ESM was/is used for heuristic use in describing patterns of individual daily experiences, evaluating common experiences of situations, and studying emotional dynamics and “other subjective states” (p. 49). ESM reports allowed the discovery of nine dimensions that moderates flow (Csikszentmihalyi, 1990), these nine dimensions had been categorized as antecedent, experience character, and consequence (Csikszentmihalyi & Csikszentmihalyi, 1992). Antecedents of flow are 1) equalized challenge and skill, 2) clarified goals, and 3) feedback[ed] was given immediately (Hancock et al., 2019, p. 102836). Experiences of flow are 4) focusing concentration, 5) merging activity and awareness, and 6) controlling of outcome (p. 102836). Consequences of flow are 7) time distortion, 8) self-awareness loss, and 9) intrinsic reward (i.e., autotelicism; p. 102836). Self-awareness loss concomitant with flow is assumed in SEP, it is reasonable to assume that of the nine dimensions, that the self-awareness loss is required. In this regard, where quantitative neurophysiological is expected to attenuate mPFC activity, and possibly additionally moderate ACC, and/or PMCs activity.
It is worth considering physiology with respect to flow, before entering neurological studies. Early psychophysiological studies of flow from de Manzano et al. (2010) used non-invasive measures of muscle tone, head movements, thoracic respiration, and heart period and blood pressure (p. 304); results found decreased heart period, increased smile (i.e., zygomaticus major/the smile muscle [p. 303]), increased respiration depth, decreased respiratory sinus arrhythmia (RSA), decreased cardiac output (increased heart period [HP], and decreased systolic blood pressure [BP]), decreased full-width-at-half-maximum (FWHM), decreased maximum blood pressure (MaxP), and decreased MaxP-minimum blood pressure (MaxP-MinP; p. 306; [p. 306]). Keller et al. (2011) measured heart rate variability and salivary cortisol; results found decreased heart rate and variability and mental workload (p. 852; [p. 850]). While useful to infer some aspects of flow from a physiological measures, this leaves weaker inferences as to neurology, which later studies address.
Ulrich et al. (2013) used arithmetic tasks to induce flow (p. 195) while under magnetic resonance imaging (MRI) with arterial spin labeling (ASL; p. 195). This research found increased blood flows in the left putamin, increased flow in the left inferior frontal gyrus (lIFG), increased blood flow in the posterior cortical regions (PCR), significantly decreased blood flow in the mPFC, and significantly decreased blood flow in the left amygdala (p. 199). These findings of significant decrease in mPFC neural activity corresponds with expected attenuation of self-concept/self-referencing.
Flow Associated Neurophysiology
Self-Reference and Sensorimotor Processing
Regarding SEP of self-referencing absent flow, there are additional studies that are related. Early studies have found that self-referential activity is stimulus independent (Teasdale et al., 1995, Antrobus et al., 1970). This has been confirmed by Goldberg et al. (2006), through research on self-introspection and sensorimotor categorization tasks, having found evidence of segregation between cortical regions responsible for each task (p. 330). As with other studies, during introspection Goldberg et al. found activation in the mPFC and lateral aspects of the PFC, with activation favoring the left hemisphere (p. 332). This activation was markedly diminished during sensorimotor processing (p. 337), in agreement with Kelley et al. (2002) and an additional study from Gusnard et al. (2001). Considering evidence of the absence of self during flow, and that sensorimotor activation also demonstrates an absence of self-related cortical regions, it may be helpful to explore some additional tangential areas associated with flow.
Tangential Areas of Flow
Enjoyment. One of the fundamental benefits of flow is its proportionality to enjoyment (Csikszentmihalyi, 1975; Jackson et al. 2008). Jo et al. (2019) had used a series of Google images associated with intrapersonal happiness, interpersonal happiness, and 200 neutral events, requesting participants to evaluate induced happiness and happiness of those in the images (p. 3). Jo et al. found wellbeing-related regions of the CMS’s mPFC, pregenual ACC (pACC), and PCC/Precuneus (p. 7). It is notable that the dopamine reward system (DRS) had not showed activation, namely the ventral tegmental area (vTA), nucleaus accumbens (NAcc), and putament, etc., however additional modeling did reveal nAcc activation and its association with reward seed systems (p. 7).
Depth of Processing (DOP). As SRE demonstrates increased recall, it is worth exploring the DOP model from a neurophysiological perspective. Otten et al. (2001) studied DOP through a recognition memory test of 280 words shown after either a prestimulus cue of “O” or “X” indicating semantic (animacy; deep encoding) or non-semantic (alphabetic; shallow encoding) properties, followed by a test for recall (p. 401). Semantic word recall was associated with the left inferior frontal gyrus, and the anterior and posterior left hippocampus, where non-semantic word recall was the left anterior hippocampus (p. 405). Notably, after investigating subsequent memory effects, the ventral left front cortex demonstrates increased activation (p. 405).
Ulrich et al.’s (2013) finding of decreased blood flow (i.e., less mPFC effort) in the mPFC during flow is congruous to mPFC’s established central role in SRE. This is additionally congruous with Gusnard et al. (2001), Kelley et al. (2002), and Goldberg et al. (2006) demonstrated segregation between self-reference and sensorimotor processing. Effecively the physiology of SEP is established physiologically. Additionally, when considering studies of enjoyment with respect to neurophysiology, well-being is associated with the CMS activity and the DRS (Jo et al., 2019). As flow is associated with decreased activation in CMS (namely mPFC), the knowledge that mPFC is activated in wellbeing demonstrates additional paradoxical effects in flow, which may lead to some questions as to how and when wellbeing is assessed. Considering research starting initially with ESM relied on interruption, it is possible that the interruption to complete an ESM self-report cued physiological response that changed states from sensorimotor processing to self-reference.
There is a great deal to comment on here beyond the scope of this literature review. Thera are many research questions relating to potential “selfing” bias in ESM and Flow State Scale (FSS; Jackson & Eklund, 2004) measures. Is it possible that enjoyment occurs through oscillations between flow and self-referencing (i.e., possibly emotion [e.g., joy]), is this oscillation parallel or serial? Additional literature review recommended to examine self-reference and enjoyment. Considering Dégeilh et al.’s (2015) revelation that SRE “seems to be a consequence of better encoding of the information than processes taking place during recogntion” (p. 1975; emphasis added), this adds weight the concept of self-nourishment. Given the role of the CMS and mPFC in self-reference, is it possible that the “self” is a misnomer? It seems the CMS may be responsible for a sensorimotor-reference effect rather than self-reference effect. This seems to better align behaviorist and humanist perspectives.
To continue, a kind of meta-top to bottom processing is at play, perhaps recollection of self, destructive of enjoyment, is due to flow-interruptive speech related areas (i.e., traditionally seen as Broca’s and Wernick’s areas) which produce neurosynaptic impulses as a result of sensorimotor phoneme formations of “I” and “self”. As tightly bound to language, self-recollection is socially conditioned, and reinforced through childhood development. Earlier self-recollections used in language used in socially dependent situations (i.e., when developing skills), are no longer needed when skills are sufficient. Does an adult need to tell their mother “I’m doing my homework?” No. An adult just does it (or not, depending on development). As an adult navigating the world, or a member navigating a skilled community, no-longer useful schemas and their associated events scripts can be detrimental to tasks at hand.
This does not just apply to the fields of psychology, because if this is that case, then what if descriptive sciences themselves are obfuscating higher realizations (it’s happened before) by holding back an as yet developed community of practice, of language (i.e., practice domain) that directly modulates local distributions of distal to proximal (i.e., world) senses sans self? These questions also bring to light additional physiological aspects of the working memory model (Baddeley & Hitch, 1974), and quite possibly physiological aspects of Freud’s original ideation of the pleasure principal and reality principal (here uncompressed for purposes of what’s about to be mentioned).
Maslow’s (1943) self-actualization is better titled flow-actualization; “self” is but a mere artifact not of neurology, but language. Pre-conceived language in literature primes for self-reference. Evidence of the SRE seems to have inspired tremendous efforts to empower memory through persistent social selfing in pursuit of personal gains—self destroys flow. It appears that overcompensation to improve memory through SRE manipulation is all over business, academia, media, and politic; overextending self/I/me through questionnaires, self-reports, diagnostics, case studies, analysis, interpretation, peer-review, practice, leadership, politics, mental health, and education. A core variable of experience is that which leads to the destruction of enjoyment is the very thing increasingly dominating social discourse—self, and its sibling, other, and its in-group, us, implying them. Another way to say this, is to enjoin another field in entirety, that of linguistic anthropology: the sign of self is linguistically relative to a destruction of cultural, linguistic, and cognitive enjoyment (i.e., optimal experience). Unfortunately, the profit of destruction is in re-construction. More research is suggested to understanding SEP through uncovering neurocorrelates of self and self-associated perceptions. It would be nice to look back having born witness to a “radical remedy before the Four Horseman saddled up again” (Csikszentmihalyi, 2014a, p. xiii)—the remedy, or weapon, is the language science leads society with, or against, itself.
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