Neural Correlates of Lyrical Improvisation: An fMRI Study of Freestyle Rap

Abstract

The neural correlates of creativity are poorly understood. Freestyle rap provides a unique opportunity to study spontaneous lyrical improvisation, a multidimensional form of creativity at the interface of music and language. Here we use functional magnetic resonance imaging to characterize this process. Task contrast analyses indicate that improvised performance is characterized by dissociated activity in medial and dorsolateral prefrontal cortices, providing a context in which stimulus-independent behaviors may unfold in the absence of conscious monitoring and volitional control. Connectivity analyses reveal widespread improvisation-related correlations between medial prefrontal, cingulate motor, perisylvian cortices and amygdala, suggesting the emergence of a network linking motivation, language, affect and movement. Lyrical improvisation appears to be characterized by altered relationships between regions coupling intention and action, in which conventional executive control may be bypassed and motor control directed by cingulate motor mechanisms. These functional reorganizations may facilitate the initial improvisatory phase of creative behavior.

Brain activity and connectivity during poetry composition: Toward a multidimensional model of the creative process

“…Consistent with previous studies [Limb and Braun, 2008; Liu et al, 2012], we find that the generation phase is marked by a dissociated pattern of activity in the prefrontal cortex: the generation of novel poems elicited increased activity throughout the MPFC but decreased activity in the DLPFC.…”

“…Importantly, these activations are above and beyond those seen during the recitation of memorized poems (which also engages the language system) suggesting that constructing novel material imposes additional demands on language areas (e.g., in selecting words that contribute to building meaning, sound and imagery within the poem). Interestingly, activated portions of the dorsal anterior cingulate cortex included the cingulate motor area, which—consistent with observations from a previous study [Liu et al, 2012]—may represent an alternative motor pathway that is engaged during the generation of improvised material. Other activated brain regions included the amygdala (which may contribute to emotional expression) as well as the hippocampus, parahippocampal gyrus, and retrosplenial cortex (which could play a role in retrieval and incorporation of autobiographical material or visuospatial imagery into new poems).…”

“…To accomplish this, we have chosen to expand upon a line of research [Limb and Braun, 2008; Liu et al, 2012] focused on artistic creativity. Using an ecologically valid approach—studying the artist during the natural act of creation—allows us to examine creative behavior as a whole and in situ, without the superimposition of unrelated, potentially confounding cognitive task demands.…”

“…The dorsolateral prefrontal cortex (DLPFC) has also been implicated, albeit in a variety of ways that will be discussed below [Bengtsson et al, 2007; Berkowitz and Ansari, 2008]. Notably, a dissociation between activity in these prefrontal regions has been reported in a series of studies: focal activation of the MPFC was coupled with deactivation of the DLPFC during both melodic and lyrical improvisation [Limb and Braun, 2008; Liu et al, 2012]. These findings suggested that the generative phase of the creative process might be associated both with increases in intrinsic motivation (related to increases in the MPFC) and attenuation of self‐monitoring and top‐down attention (related to decreases in the DLPFC).…”

“…In this study, we evaluate the quality of the creative product by assessing the responses of an audience, in this case an independent panel of experts, to the poems subjects produced. Previous studies rated the complexity or novelty of improvised musical [Bengtsson et al, 2007; Villarreal et al, 2013] or literary material [Liu et al, 2012; Shah et al, 2013] and correlated these measures with the amplitude of brain activity. Other studies utilizing sensorimotor tasks [Baldassarre et al, 2012; Koyama et al, 2011] have suggested that performance is strongly associated with functional connections between brain regions.…”