A Rare Form of Dementia Can Unleash Creativity

0
47
A Rare Form of Dementia Can Unleash Creativity



Neurological conditions can release a torrent of new creativity in a few people as if opening some mysterious floodgate. Auras of migraine and epilepsy may have influenced a long list of artists, including Pablo Picasso, Vincent van Gogh, Edvard Munch, Giorgio de Chirico, Claude Monet and Georges Seurat. Traumatic brain injury (TBI) can result in original thinking and newfound artistic drive. Emergent creativity is also a rare feature of Parkinson’s disease.

But this burst of creative ability is especially true of frontotemporal dementia (FTD). Although a few rare cases of FTD are linked to improvements in verbal creativity, such as greater poetic gifts and increased wordplay and punning, enhanced creativity in the visual arts is an especially notable feature of the condition. Fascinatingly, this burst of creativity indicates that the potential to create may rest dormant in some of us, only to be unleashed by a disease that also causes a loss of verbal abilities.

[Read more about frontotemporal dementia]

The emergence of a vibrant creative spark in the face of devastating neurological disease speaks to the human brain’s remarkable potential and resilience. A new study published in JAMA Neurology examines the roots of this phenomenon and provides insight into a possible cause. As specific brain areas diminish in FTD, the researchers find, they release their inhibition, or control, of other regions that support artistic expression.

Frontotemporal dementia is relatively rare—affecting about 60,000 people in the U. S.—and distinct from the far more common Alzheimer’s disease, a form of dementia in which memory deficits predominate. FTD is named for the two brain regions that can degenerate in this disease, specifically the frontal and temporal lobes. Not every person with FTD has the same pattern of loss in these regions; instead there are several variants. For example, degeneration in the temporal lobes, which are the seat of language in the brain, leads to difficulties in producing and understanding written and spoken communication. Some people with FTD have impaired speech production in what is called nonfluent FTD. Others may have difficulty in understanding word meanings in semantic FTD.

People with FTD also experience degeneration in the frontal lobes, which typically engage in a suite of skills related to social behavior, empathy, planning and decision-making. Impairment there can lead to poor judgment and difficulty understanding the perspectives of others. The frontal lobes are also involved in the complex interplay of brain areas that supports our social behavior, helping to balance baser desires and urges with the understanding of social norms and morals. In a healthy brain, the frontal lobe’s activity can inhibit activity in other regions. This interchange is how the brain quells, for instance, the knee-jerk use of rude language with the understanding that such responses can cause offense. In FTD, however, researchers suspect that damage to the frontal lobes impairs their ability to suppress other brain activity. Behavior becomes disinhibited and socially inappropriate.

In a similar way, the recent study suggests that loss of temporal lobe activity somehow disinhibits artistic creativity in some individuals. In this new work, the researchers reviewed the medical records of 689 people with FTD or related disorders, looking for evidence of new or increased interest in artistic activities. In total, they found this change in 17 people—or 2.5 percent of their FTD participants. Most of these individuals painted, although some drew, sculpted, made pottery, crafted jewelry or quilted. FTD can sometimes be linked to certain genes, but none of these individuals had any known genetic cause of their dementia. Most in this artistic group had either the semantic or nonfluent variant of the disease, suggesting that FTD significantly affected their temporal lobe.

See or Speak?

Researchers then selected people to compare with this artistic group. One set included FTD patients who were similar to the artists in many ways (including their diagnosis, age, sex and education) but did not exhibit artistic tendencies. An additional group matched the artists demographically (in age, sex, education and other factors) but did not have any form of dementia or serious health concern.

The research team used magnetic resonance imaging (MRI) to compare these three sets of people. Significantly, brain scans revealed that people with FTD had reduced volume in their left temporal lobe—an area that is important for speech production—when compared with healthy individuals. That atrophy was more pronounced in the artistic group than in those without artistic tendencies.

The scientists also found that some brain areas were relatively larger among artists with FTD. In particular, people with a smaller temporal lobe had greater volume in their dorsomedial occipital lobe, a region involved in visual association, when compared with FTD patients who were not artistically driven. This finding implies that while the temporal lobes were impaired by FTD, this visual area was enhanced. Further, among the visual artists with FTD, the portion of the motor cortex that controls movement in the right hand also showed a relative increase in volume. In fact, the greater the volume of the dorsomedial occipital lobe, the greater was this motor cortex volume.

Taking the evidence together, the researchers concluded that this disease’s effects on the temporal lobe may result in less control over the brain region that generates visual associations. In consequence, the creative drive is unleashed. Meanwhile the increased volume of the brain area that controls the right hand likely reflects the use of that hand in creating art.

The researchers confirmed these ideas by observing brain changes in one individual as her FTD progressed and creativity emerged. Positron-emission tomography scans measured how much energy was being used by different regions of her brain. Comparing brain scans revealed that, as the woman’s dementia progressed, her frontal and temporal lobes became significantly less active—and the areas involved in visual association became more active.

The new study suggests that, in a healthy brain, the temporal lobe is directly or indirectly inhibiting activity in the dorsomedial occipital lobe, which supports visual association. But why would a part of the brain involved in verbal processing suppress visual regions? These finding suggests a reciprocal or even competitive relationship between our verbal abilities and visual artistic creativity.

This insight is actually at the heart of a hypothesis regarding how our brain has changed over the course of human evolution: the “superior visual perception hypothesis.” Vision demands a lot of our brain’s computational capacity—so much so that we often close our eyes to concentrate on what we hear, whether it is music, speech, birdsong or crashing waves. According to the evolutionary hypothesis, when our species first began to develop language, the brain diverted computational capacity from visual processing to support this new activity.

For example, visual processing helps us comprehend gesture, a nonverbal form of communication that likely preceded our use of verbal language. Computational tasks that supported the production and interpretation of gesture were also relevant to speech, and so, as we became more adept at language, gesture lost its primacy in communication. The brain regions responsible for gesture could have been taken over by those used in speech through an evolutionary process called exaptation, wherein parts of an organism take on different or completely novel roles.

This hypothesis may explain why areas involved in verbal processing might somehow tamp down activity linked to visual thinking. The new FTD research suggests this evolutionary process is, in a sense, undone in these artists with dementia.

Emerging Artist

Brain injury and neurodegenerative disease often have tragic consequences. It is therefore remarkable that these conditions can have a seemingly positive effect, such as enhanced creativity—and the finding can help us understand the origins of innovation. Creativity is part of humanity’s essence and distinguishes us in some ways from our hominid relatives. Is it possible that an artist is hidden in all of us, awaiting an accidental emergence?

Creativity is a complex behavior that requires several elements, including the capacity for divergent and symbolic thought, persistence despite uncertainty, skill in execution and the ability to evaluate one’s creations. When considering the burst in artistic activity sometimes seen in FTD, all of these factors should be weighed. In general, people with FTD perform poorly on tests of divergent thinking, suggesting either that this group of artists with the condition is quite distinct from other individuals who have it or that different aspects of creativity are somehow enhanced in the FTD artists. Other studies find that aesthetic judgment is retained in FTD, allowing affected people to evaluate the strength of their finished artwork, although many struggle to recognize emotional content in visual art.

Past research has also demonstrated that creativity emerges when we loosen our self-critical thinking. In FTD, a lack of self-censorship contributes to socially inappropriate behavior, for example, and may also mean that an artist’s “inner critic” is less vocal. Yet another facet of artistic success is practice. FTD is often accompanied by perseverative behavior in which people repeat the same actions or statements or become mentally stuck in an idea or behavior. Some scientists have proposed that the FTD artist benefits from the combination of behavioral disinhibition and repetitive practice. Indeed, that could also help explain the literary output of poetic people with FTD, who, unlike visually artistic people with the condition, have been spared significant losses to the temporal lobes’ language areas.

Still, none of these ideas fully explain the flourishing of artistic behavior in some people with FTD. The authors of the new study emphasize that the FTD artists were only a small percentage of the total number of people with this dementia that they sampled. Other factors, such as an artistic predisposition and an environment or circumstances conducive to creative pursuits, may be important.

The FTD artist may be at the center of a perfect creative storm. Studies of these individuals can therefore reveal the subtle interplay between brain regions that manifest in remarkable behaviors. The complexity of creativity makes it even more incredible that such ability can be a consequence of neurodegeneration. Ultimately, these findings are a humbling reflection of the human brain’s adaptability and seemingly endless capabilities.

Are you a scientist who specializes in neuroscience, cognitive science or psychology? And have you read a recent peer-reviewed paper that you would like to write about for Mind Matters? Please send suggestions to Scientific American’s Mind Matters editor Daisy Yuhas at pitchmindmatters@gmail.com.

This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.



Source link