How differences in the brains of autistic people can explain their difficulties
Scientists investigating the brain of one of the world’s most famous autistic people have found several features that can explain her unique talents.
Temple Grandin, professor of animal sciences at Colorado State University, is what is known as a ‘savant’ – someone who shows some of the social deficits of autism yet also has some exceptional abilities.
A tireless campaigner for autism research and awareness she is known for her exceptional non-verbal intelligence, spatial reasoning, sharp visual acuity and an uncanny gift for spelling and reading.
Savant: Professor Temple Grandin, left. Unlike controls (top right), Professor Grandin has lateral ventricles (bottom right) that are significantly larger on the left side of her brain than on the right
The subject of an award-winning eponymous-titled biographical film starring Claire Danes, Professor Grandin was also in 2010 listed in the Time 100 list of the 100 most influential people in the world in the ‘Heroes’ category.
In a bid to understand her cognitive gifts, and the accompanying weaknesses, a group of neuroscientists gave the professor a series of psychological tests and scanned her brain using several imaging processes.
Jason Cooperrider, a graduate student at the University of Utah who presented the work at the Society for Neuroscience’s annual meeting, explained their aims to the Simons Foundation Autism Research Initiative.
‘We asked how might brain structure and function be related to both outstanding ability and outstanding disability — the autism — within the same brain,’ he said.
The professor received exceptionally high scores on several psychological assessments, including tests of reading, spelling and spatial reasoning.
She achieved a phenomenal perfect score on Raven’s Coloured Progressive Matrices test, which assesses non-verbal reasoning. Her weakest skill was found to be verbal working memory.
Scans showed Professor Grandin’s brain is significantly larger than that of three matched neurotypical control subjects – something seen in some children with autism but which scientists do not yet understand.
Her lateral ventricles – chambers which hold cerebrospinal fluid – are different in size, with the left much much larger than the right, a finding Mr Cooperrider described as ‘quite striking’.
On both sides, the professor possesses unusually large amygdala, sectors of the brain which are part of the limbic system and have been shown to perform a primary role in the processing of memory and emotional reactions.
The researchers also traced white-matter connections in Professor Grandin’s brain using diffusion tensor imaging, finding what they dubbed ‘enhanced’ connections in the left precuneus, a region involved with episodic memory, visuospatial processing, reflections upon self, and aspects of consciousness.
WHAT IS AUTISM?
Autism is a lifelong developmental disability that affects how a person communicates with, and relates to, other people. It also affects how they make sense of the world around them.
It is a spectrum condition, which means that, while all people with autism share certain difficulties, their condition will affect them in different ways.
Some people with autism are able to live relatively independent lives but others may have accompanying learning disabilities and need a lifetime of specialist support. People with autism may also experience over- or under-sensitivity to sounds, touch, tastes, smells, light or colours.
Asperger syndrome is a form of autism. People with Asperger syndrome are often of average or above average intelligence. They have fewer problems with speech but may still have difficulties with understanding and processing language.
(Source: The National Autistic Society)
They found she also has enhanced white matter in the left inferior fronto-occipital fasciculus. This region connects the frontal and occipital lobes, which might explain the professor’s keen visual acuity, the researchers said.
In keeping with the double-edged nature of Professor Grandin’s condition, she also has some weak connections, which the researchers said were defined in part by decreased integrity of brain-tissue fibres.
One weak area was her left inferior frontal gyrus, which includes the famous Broca’s area, which has functions linked to speech production and impairment of which can leave brain injury sufferers mute. Professor Grandin’s right fusiform gyrus – a brain region involved in facial and body recognition – also had compromised connections.
The findings agreed with the professor’s own personal assessments of her abilities. She has previously written how words are, for her, only understood when translated into pictures and described how she finds socialising ‘boring’.
She has noted in her autobiographical works that autism affects every aspect of her life.
She has to wear comfortable clothes to counteract her sensory integration dysfunction and has structured her lifestyle to avoid sensory overload.