Running head : DAYDREAMING AND BRAIN CONNECTIVITY 1 Daydreaming Styles and Brain Functional Connectivity

Intrinsic modes of thinking, like daydreaming, are in large part related to more general thinking styles. Through neuroimaging techniques, we are able to identify daydreaming connectivity within brain networks. The brain’s default mode network is typically associated with unintentional thinking, while the fronto-parietal network involves more intentional forms of cognition. In this study, resting brain states were collected, and participants completed the Short Imaginal Process Inventory (SIPI) to ascertain distinctive daydreaming patterns among the individuals, including positive constructive (PC), guilt and fear of failure (GF), and poor attentional control (PA) styles. Connectome-based predictive modeling was used to estimate the pattern of each participant’s daydream connectivity from whole-brain, resting-state functional connectivity. In PC individuals, node connections found within frontal-parietal and default mode networks, which supports previous evidence of default mode activity associated with goaldirected cognition. Limbic network connectivity in GF individuals suggests more emotional qualities within their daydreams. Dorsolateral prefrontal cortex and subcortical/cerebellum activity in PA individuals suggests low maintenance of attention, as previously found in ADHD individuals. By delving into the individual differences of daydreaming styles, our research has contributed to a more comprehensive understanding of overall brain functional connectivity as it pertains to the intentionality and characteristic quality of different daydreamers. DAYDREAMING AND BRAIN CONNECTIVITY 3 Daydreaming Styles and Brain Functional Connectivity Daydreaming, commonly referred to as mind wandering, can be classified into two broad categories of deliberate and spontaneous thought. Deliberate cognition often incorporates goaldirected and task-related thought processes. Conversely, spontaneously occurring cognition involves less purposeful and involuntary thinking that frequently occurs with little to no task demands (Christoff, Ream, & Gabrieli, 2004). Past research on mind wandering has found intentional and unintentional mind wandering to be separate processes of our cognitive experience (Seli, Risko, Smilek, & Schacter, 2016). Recent neuroimaging observations have studied the connectivity of different brain networks in relation to spontaneous (unintentional), and deliberate (intentional) thought, which suggest commonalities between these two dissociable cognitive processes. The present research investigates different styles of daydreaming to help dissociate these two types of thought and to see whether each daydreaming profile can be predicted from functional brain networks. One brain system commonly associated with daydreaming is the default mode network. This system takes part in the brain’s internal cognition, and it is primarily active when an individual is not focused on the external environment (Buckner, Andrews-Hanna, & Schacter, 2008). It was once thought that the activation of regions within this network could only occur while the brain is at rest or contributing to low processing demands (Grafton, Horn, Macrae, Mason, Norton, & Wegner, 2007), thus providing more susceptibility to mind wander during these periods of low external stimulation. Hence, it is associated with imaginative processes that include spontaneous mind wandering (Beaty et al., 2014), but these processes may also elicit deliberate mind wandering. DAYDREAMING AND BRAIN CONNECTIVITY 4 In contrast, the fronto-parietal network, which includes regions of the anterior prefrontal cortex and inferior frontal gyrus, contributes to more intentional thought and cognitive control (Vincent et al., 2008). Additionally fronto-parietal connections have also been attributed with goal-orientation, decision-making, and task-specific activation (Dosenbach et al., 2007). It is these executive processes that give rise to deliberate mind wandering that involves the initiation or continuation of a mind wandering episode (Seli et al., 2016). Recent research suggests that the default mode network can couple with other networks, such as the fronto-parietal network, during mind wandering (Spreng, Stevens, Chamberlain, Gilmore, & Schacter, 2010). This contradicts the previous understanding of the DMN remaining a distinct network, active only in spontaneous mind wandering. Measuring resting-state brain activity provides a suitable window into spontaneous thought processes, which can include daydreaming. Previous research has revealed correlations between self-generated thought including mind wandering, future thinking, creative cognition, and daydreaming to DMN activity (Beaty et al., 2015). Mason et al. (2007) examined individual tendencies to produce stimulus-independent thoughts that were correlated with DMN activity, in which participants completed a daydreaming scale determining individual propensities of engaging in these thoughts (Buckner, 2008). Resting-state neuroimaging may also provide time for intentional mind wandering, which is often accompanied with the executive processes associated with fronto-parietal connectivity (Christoff et al., 2009; Seli et al., 2016). It can be assumed that daydreaming patterns highly associated with characteristics of personality may show similar network distinctions and interactions in resting-state brain activity. Beaty and colleagues (2018), for example, have found that individuals higher in openness tend to spend DAYDREAMING AND BRAIN CONNECTIVITY 5 more time in a default-mode and fronto-parietal connected brain network during resting-state scans. Short Imaginal Process Inventory Much of our time is spent in spontaneous cognition. Whether it is through thoughts of the past, present, or future, these self-generated thoughts are subjective cognitive experiences that reflect personality traits and the context in our daily lives (Kane et al., 2017). Kane and colleagues (2017), for example, found that openness to experience was a predictor of mind wandering tendencies and that individuals higher in openness frequently mind wander in everyday life settings. These intrinsic thought processes take place in the form of internal conversations, imagery, or daydreams that contribute to our human experience and “stream of consciousness” (Buckner, 2007). The Short Imaginal Process Inventory (SIPI) is a widely used scale for measuring daydreaming patterns. The SIPI is a shorter, 45-item measure, developed from the original 400item Imaginal Process Inventory (IPI). The SIPI contains three subscales that classify distinct daydreaming styles: positive-constructive, guilt and fear of failure, and poor attentional control. The positive-constructive subscale is accompanied with positive thoughts, acceptance, playful/wish-fulfilling fantasies, and problem solving (Gruis, 2005; Singer & Zhiyan, 1997). It is often expressed through future thinking and vivid auditory and visual imagery (Gruis, 2005). The guilt and fear of failure subscale includes frightened reactions to daydreams, fear of failure, fear of doing something wrong, and hostile daydreams. This style of daydreaming also involves achievement by heroic actions. Lastly, the poor attentional control dimension involves poor maintenance of control, easy loss of interest, boredom susceptibility, and distractibility. It is DAYDREAMING AND BRAIN CONNECTIVITY 6 possible for an individual to experience all three patterns, but their daydreams often gravitate towards one style (Gruis, 2005). Research on individual differences have successfully linked traits of personality to these different patterns of daydreaming, concluding that openness to experience was associated with positive constructive daydreaming, guilty-dysphoric was linked with neuroticism, and poor attentional was negatively correlated with conscientiousness (Singer & Zhiyan, 1997). The act of daydreaming often carries a negative connotation to it, but the style of positive constructive daydreaming allows more acceptance and openness towards the action of daydreaming. This openness to daydreaming is reflected in the basic description from one of the Big Five personality traits, Openness to Experience (McCrae & John, 1992). Openness elicits a form of sensitivity to new experiences, which is mirrored with positive constructive daydreaming sensitivity to the act of daydreaming. Guilty-dysphoric daydreaming was associated with neuroticism as each dimension expresses more depressive cognition. Some literature has suggests that neuroticism in spontaneously self-generated thoughts is associated with creativity as a result of prolonged periods of rumination (Perkins, Arnone, Smallwood, & Mobbs, 2015). Others counter this research, suggesting that self-generated thoughts in neurotic individuals do not lead to creative thinking but rather to more aversive rumination (Pickering et al., 2016). In Singer and Zhiyan (1997), a negative correlation was found between conscientiousness and poor attentional control, illustrating that poor control over one’s internal thoughts is consequently associated with less conscientiousness, or control. The daydreaming styles within the SIPI had yet to be mapped out in the brain until the present study. However, various studies have provided neural correlates for key characteristics of each profile. Positive constructive daydreaming, for example, involves planning and thinking DAYDREAMING AND BRAIN CONNECTIVITY 7 about the future. Some studies have observed this future cognition in the brain, including Addis and colleagues (2007) in their assessment of episodic construction of events, which determined active brain areas that mostly included default mode regions (parietal lobule, temporal gyrus, cuneus). Future event construction tasks yielded more fronto-parietal activity with regions including the frontal gyrus, anterior cingulate cortex, and frontal pole. For poor attentional control, daydreams are characterized by