**7. Neural basis of creativity in ASD**

We are not aware of any studies investigating directly the neural basis of creativity in au‐ tism apart from studies exploring savant skills in autism. Some of these support the Left Hemisphere (LH) dysfunction/ and Right Hemisphere (RH) compensation theory [e.g. 96] as indicated by hemispheric asymmetry. Research evidence of neuroanatomical abnormalities including atypical minicolumnar organization in ASD [97,98] as well as neural hypotheses about abnormal connectivity [e.g. 99] support this theory.

#### **7.1. Hemispheric asymmetry**

Cerebral asymmetry refers to the lack of structural symmetry in left and right hemispheres in humans. Atypical cerebral asymmetry, a deviation from the normal pattern of cerebral asymmetry has been associated with special cognitive talents [100] and creativity [101] as cited by Smalley et al. [102]. For example, the capability for making distal or global verbal associations is one factor contributing to creativity and according to Brugger and Graves [103] the basis for this type of verbal creativity is "cerebral laterality in which an individual has a relative weakening of left hemisphere dominance and strengthening of availability of right hemisphere processing" [104] p. 138.

Atypical cerebral asymmetry has been associated with autism, dyslexia and ADHD [105], neurodevelopmental disorders considered to share regions of linkage overlap [106]. In addi‐ tion, creativity in psychiatric populations is often associated with atypical cerebral asymme‐ try [107] and a RH "bias" [108].

Research evidence for atypical cerebral asymmetry in autism (e.g. increased size of some RH cortical structures) and reversed lateralization of language has been well documented [e.g. 109]. An imaging study by Herbert et al [110] found a "sizeable right-asymmetry increase" in subjects with autism. Individuals with autism had twice as much right-as left-asymmetri‐ cal cortex than the control sample. This finding was interpreted as a consequence of early abnormal brain growth abnormalities. According to the hypothesis put forward by Gesch‐ wind and Galaburda [111] the immaturity of the LH in utero makes it more susceptible to damage, which could result in a compensatory overdevelopment of the RH caused by neu‐ ral migration and thus resulting in an anomalous RH-dominance. As the RH develops earli‐ er than the LH, accelerated early brain development in autism may lead to anomalous lateralization of cognitive functions as suggested by Herbert et al [112].

#### **7.2. Right hemisphere processing and creativity**

areas in a fluid analogy-making task comes from an fMRI study [94] indicating bilateral neu‐ ral activations. A study measuring differences in cerebral blood flow between highly crea‐ tive individuals and controls during a verbal task of creative thinking [95] implicated a neural network consisting of right and left fronto-temporal, parietal, and cerebellar regions in highly creative performances. These areas are involved in cognition, emotion, working

We are not aware of any studies investigating directly the neural basis of creativity in au‐ tism apart from studies exploring savant skills in autism. Some of these support the Left Hemisphere (LH) dysfunction/ and Right Hemisphere (RH) compensation theory [e.g. 96] as indicated by hemispheric asymmetry. Research evidence of neuroanatomical abnormalities including atypical minicolumnar organization in ASD [97,98] as well as neural hypotheses

Cerebral asymmetry refers to the lack of structural symmetry in left and right hemispheres in humans. Atypical cerebral asymmetry, a deviation from the normal pattern of cerebral asymmetry has been associated with special cognitive talents [100] and creativity [101] as cited by Smalley et al. [102]. For example, the capability for making distal or global verbal associations is one factor contributing to creativity and according to Brugger and Graves [103] the basis for this type of verbal creativity is "cerebral laterality in which an individual has a relative weakening of left hemisphere dominance and strengthening of availability of

Atypical cerebral asymmetry has been associated with autism, dyslexia and ADHD [105], neurodevelopmental disorders considered to share regions of linkage overlap [106]. In addi‐ tion, creativity in psychiatric populations is often associated with atypical cerebral asymme‐

Research evidence for atypical cerebral asymmetry in autism (e.g. increased size of some RH cortical structures) and reversed lateralization of language has been well documented [e.g. 109]. An imaging study by Herbert et al [110] found a "sizeable right-asymmetry increase" in subjects with autism. Individuals with autism had twice as much right-as left-asymmetri‐ cal cortex than the control sample. This finding was interpreted as a consequence of early abnormal brain growth abnormalities. According to the hypothesis put forward by Gesch‐ wind and Galaburda [111] the immaturity of the LH in utero makes it more susceptible to damage, which could result in a compensatory overdevelopment of the RH caused by neu‐ ral migration and thus resulting in an anomalous RH-dominance. As the RH develops earli‐ er than the LH, accelerated early brain development in autism may lead to anomalous

lateralization of cognitive functions as suggested by Herbert et al [112].

memory and response to novelty.

778 Recent Advances in Autism Spectrum Disorders - Volume I

**7.1. Hemispheric asymmetry**

right hemisphere processing" [104] p. 138.

try [107] and a RH "bias" [108].

**7. Neural basis of creativity in ASD**

about abnormal connectivity [e.g. 99] support this theory.

Savant skills are linked to the RH [113], which is dominant for attention, visuospatial and emotional function. Various authors [114-115] have suggested that autistic savants have atypical LH dysfunction with RH compensation. Based on research evidence including imaging studies Treffert [116] speculated that "one mechanism in some savants, whether congenital or acquired is left brain dysfunction with right brain compensation." The notion of "paradoxical functional facilitation" as described by Kapur [117] denotes loss of function in one damaged brain area and enhanced function of another area, which as emphasized by Treffert is "central to explaining savant syndrome" (p.1356).

RH skills can be characterized as non-symbolic, artistic, concrete and directly perceived in contrast to LH skills that are more sequential, logical, and symbolic. For example musical, artistic, visual or spatial abilities (mathematics) are primarily RH skills.

The association between RH and creativity is based on research evidence demonstrating that the RH is more involved in production of mental images than the LH, perception and pro‐ duction of music, e.g. the right inferior frontal gyrus is known to be involved in musical pitch encoding and melodic pitch memory [118]. EEG studies show that highly creative indi‐ viduals show more right than left-hemisphere activation during experimental studies [119], indicating that during the creative process creative individuals rely more on the RH. Lesion studies as well as unimpaired population studies have demonstrated that the RH is superior to the LH at noticing anomalies in objects [120]. Individuals with autism are well known for detecting even the smallest changes in the environment.

In sum, several lines of evidence suggest that atypical cerebral asymmetry which is a highly heritable trait [121] is associated with autism and linked to certain aspects of creativity. It is also likely that some of the structural brain abnormalities evidenced in autism are related to the special cognitive functioning that encourages great creativity. Neurological brain differ‐ ences have been reported in the literature on creativity [122].

#### **7.3. Neuroanatomical abnormalities in autism**

Converging neuroscientific evidence has suggested that the neuropathology of ASD is wide‐ ly distributed, involving impaired connectivity throughout the brain. Neuroanatomical ab‐ normalities in autism include increase in cortical thickness [123], and increase in head and brain size [124]. Accelerated growth in brain size in early childhood in autism has been documented by a range of studies [125], which may be consistent with the asymmetric cere‐ bral lateralization in autism as discussed above. The increased brain volumes in autism are believed to be the result of insufficient or abnormal prenatal pruning, which together with genetic factors are most likely to underlie these growth abnormalities [126]. In addition, there is evidence of higher birth weight [127] and faster body growth [128] as well as in‐ creased levels of growth hormones [129] in autism. These altered brain growth rates are con‐ sidered to have a strong influence on patterns of brain connectivity and cerebral lateralization [130, 131] and differential cognitive functioning. For example, the increased hippocampus size in autism [132] may be associated with enhanced visual-spatial, mathe‐ matical and mechanistic processing in autism as well as savant abilities such as calculation and memory. Imaging data of a reduced size of corpus callosum in autism [133] is consistent with the reduced interhemispheric brain connectivity reported in autistic individuals [134]. Neural underconnectivity [e.g. 135] provides support for the weak "central coherence theo‐ ry" which postulates enhanced local and decreased global information processing in autism. Research on patterns of cortical connectivity also indicates that a specific minicolumnar phe‐ notype found in autism may be beneficial for information processing and/or focused atten‐ tion and may also offer an explanation for the savant abilities autism [136, 137].

**9. Novelty, ADHD and creativity**

sharing regions of linkage overlap [149,150].

an increase in novel ideas, they may not always be appropriate.

would be taken over by accountants" (p.124).

**11. Conclusion**

**10. Psychopathology**

The majority of theoretical conceptions of creativity agree that the main component of crea‐ tivity is its novelty, uniqueness or unusualness that undoubtedly applies to the creativity displayed by gifted individuals with ASD. Novelty or sensation seeking behaviour is also strongly associated with ADHD. A significant degree of comorbidity between autism and ADHD has been documented [e.g. 147] in the literature. Although reported to have poor at‐ tention and concentration and being poor academic performers individuals with ADHD have a capacity to hyperfocus, which allows them to produce great works of art. For exam‐ ple the poetry of Lord Byron, who had ADHD [148] is an example for a work of genius in this area. As pointed out above, both autism and ADHD are associated with atypical cere‐ bral asymmetry which is a highly heritable and complex phenotype linked to creativity and

Critical Evaluation of the Concept of Autistic Creativity

http://dx.doi.org/10.5772/54465

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There is a very close relationship between creativity (especially in literature and arts) and psychopathology, particularly mood disorder [151, 152]. An association of biochemical fac‐ tors in psychosis and creativity has been suggested by Folley et al [153] indicating the nora‐ drenergic system. This model also provides possible links between attention, divergent thinking, and arousal based on mechanisms that interact with structural and neurochemical systems of the brain and has the potential to explain the novelty seeking behaviour implicat‐ ed in ADHD but may have less explanatory power as far as autism is concerned. According to Sternberg and Lubart [154] creativity and novelty must be coupled with appropriateness for something to be considered creative. Although schizotypal thought most likely leads to

In contrast, the nature of creativity displayed by individuals with ASD is associated with the distinctiveness of the autistic brain and its unique neural connectivity. In this context Tem‐ ple Grandin [155] has stated, "it is likely that genius is an abnormality" (p178-179). Howev‐ er, she also believes that autistic intelligence is necessary in order to add diversity and creativity to the world: "It is possible that persons with bits of these traits are more creative, are possibly even geniuses…If science eliminated these genes, maybe the whole world

The results of our evaluation suggest that many features of ASD are advantageous for great creativity. Creativity is an extremely complex and multifaceted construct and no cognitive theory or model of brain function has so far been able to fully account for it. We suggest that the distinctive gifts of perception, attention, memory and information

To conclude, although neural mechanisms underlying savant skill and development are not well established, associating creativity with hemisphere lateralization and anatomical abnormalities in autism is supported by empirical evidence and also has some explanato‐ ry potential. Additional areas to explore are genetic factors and creativity found in other pathological conditions.

#### **8. Nature versus nurture**

Is great creativity a fortunate combination of specific traits, or do "creativity genes" exist? As speculated by Smalley et al [138] "genes that increase one's risk for certain psychiatric or learning disorders may also be 'enhancer' genes for creativity (and intuition)" (p.82). Ac‐ cording to Gardner [139] it is extremely unlikely that there is such a thing as a "poetry gene or a music gene" since complex human behaviours typically have a "polygenic basis" (p. 175). Without doubt ASD have a polygenic basis and genetic factors not only contribute to specific skills but also to traits such as persistence, the capacity for concentration for extend‐ ed periods, and curiosity about certain types of stimulation. Lykken et al [140] describe the concept of *emergenesis*, an extreme form of epitasis, in which a unique combination of genes may lead to qualitative shifts in capacity or ability that may apply to extremely gifted indi‐ viduals with ASD.

The relationship between inherited talent and/or extensive practice is a very contentious as‐ pect of superior ability in specific skills. The view propounded by Howe [141] emphasizing the overwhelming role of practice in the acquirement of special skills, is largely rejected by a majority of theorists who argue for the role of innate talent [142-144]. Special talents are es‐ sentially innate in predisposing to cognitive or physical qualities and are the key to under‐ standing geniuses from Einstein to Mozart [145]. For example, research evidence from twin data [146] suggests a genetic basis for detail-focused cognitive style predisposing to talent in ASD. It is configuration of genes and variations in genetic inputs that are critical to the suc‐ cess in persons of great creativity. It is our belief that there are significant genetic underpin‐ nings to creativity of genius proportions, which of course could not be expressed without environmental factors.
