番茄社区

Sparks of visual artistic creativity occurred early in frontotemporal dementia and were disproportionately observed in patients with temporal lobe-predominant degeneration, a case-control study showed.

This burst of visual art expression was associated with damage to brain regions that normally suppress dorsomedial occipital cortex function, reported Bruce Miller, MD, of the University of California San Francisco (UCSF), and co-authors in .

Frontotemporal dementia is a heterogeneous group of dementias with progressive atrophy involving the frontal or temporal lobes, or both. New artistic skills have been reported in some patients with frontotemporal dementia, particularly those with primary progressive aphasia variants.

The UCSF study involved 17 frontotemporal dementia patients with emergent visual artistic creativity. The research stemmed from clinical about a non-artistic businessman with frontotemporal dementia "who unexpectedly started to produce marvelous paintings," noted co-author Adit Friedberg, MD, also of UCSF.

"Remarkably, this new talent emerged in proximity to the occurrence of his language difficulties," Friedberg told 番茄社区. "Subsequently, other reports of patients with frontotemporal dementia -- as well as other lesions affecting the same brain regions -- have recapitulated this phenomenon."

The underlying mechanism was unknown, Friedberg noted. "It has been speculated that decreased inhibition or release of posterior systems involved in visual perception and association may have contributed to this unexpected gain of function; however, this hypothesis was never systematically examined."

In a UCSF cohort of 689 frontotemporal dementia patients from 2002 to 2019, 17 met the definition of emergent visual artistic creativity, resulting in a prevalence of 2.5%. Eight of the 17 patients had new visual artistic skills, seven had a past interest in art, and two were artists who had a substantial change in visual style.

Visual art included painting, quilting, jewelry making, sculpture, pottery, and montage. Art rarely focused on human faces, and bright colors were common.

Ten of the 17 patients were women, and mean age was 65. The most frequently associated clinical syndrome was the semantic variant of primary progressive aphasia, which accounted for about half of the cases (8 of 17). In most patients, emergent visual artistic creativity occurred around the time of frontotemporal dementia symptom onset, but in four patients it happened before symptoms appeared.

The case-control study matched the 17 visually artistic patients with 51 frontotemporal dementia patients who were not visually artistic and 51 healthy controls.

Emergent visual creativity was seen in 47% of patients with temporal lobe-predominant degeneration. Atrophy network mapping showed an inverse functional correlation between frontotemporal dementia atrophy and dorsal occipital cortex in healthy controls. This region is part of the dorsal visual stream that projects to the posterior parietal cortex, the researchers noted.

This inverse correlation appeared in 100% of frontotemporal patients with emergent visual creativity and 88% of patients who were not visually artistic.

"We combined several state-of-the-art neuroimaging analysis techniques to demonstrate that, indeed, in frontotemporal dementia there is a disinhibition of a specific region in the dorsal occipital cortex," Friedberg said. "In some patients who are either genetically predisposed or who operate in a conducive environment, this disinhibition manifests as emergent visual creativity."

"We also found that in artists with frontotemporal dementia, there was a unique structural relationship between the disinhibited region in the dorsal occipital cortex and the cortical region where the right hand is represented," she added. "We think that this structural signature may reflect neuroplasticity secondary to the intense artistic occupation."

These results generated a novel hypothesis about the mechanisms underlying the emergence of visual creativity in frontotemporal dementia, opening the door to future research about enhanced capacities that may appear early in neurodegenerative disease, the researchers noted.

"Our findings suggest that neuroplastic processes may occur in parallel to the disease process and may be potentially leveraged to develop new therapies," Friedberg said. They also shed light on the role of visual perceptual regions in visual creativity, she added.

The study is limited by its small sample size, the researchers acknowledged, though this cohort of visually artistic frontotemporal dementia patients is the largest to date.

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