Autism: Difficulty in Recognising Faces Linked to Performance in a Group of Neurons

Neuroscientists at Georgetown University Medical Center (GUMC) have discovered a brain anomaly that explains why some people diagnosed with autism cannot easily recognise faces -- a deficit linked to the impairments in social interactions considered to be the hallmark of the disorder.

They also say that the novel neuro-imaging analysis technique they developed to arrive at this finding is likely to help link behavioural deficits to differences at the neural level in a range of neurological disorders.

The final manuscript published March 15 in the online journal NeuroImage: Clinical, the scientists say that in the brains of many individuals with autism, neurons in the brain area that processes faces (the fusiform face area, or FFA) are too broadly "tuned" to finely discriminate between facial features of different people.

They made this discovery using a form of functional magnetic resonance imaging (fMRI) that scans output from the blueberry-sized FFA, located behind the right ear.

"When your brain is processing faces, you want neurons to respond selectively so that each is picking up a different aspect of individual faces. The neurons need to be finely tuned to understand what is dissimilar from one face to another," says the study's senior investigator, Maximilian Riesenhuber, PhD., an associate professor of neuroscience at GUMC.

"What we found in our 15 adult participants with autism is that in those with more severe behavioral deficits, the neurons are more broadly tuned, so that one face looks more like another, as compared with the fine tuning seen in the FFA of typical adults," he says.

"And we found evidence that reduced selectivity in FFA neurons corresponded to greater behavioral deficits in everyday face recognition in our participants. This makes sense. If your neurons cannot tell different faces apart, it makes it more difficult to tell who is talking to you or understand the facial expressions that are conveyed, which limits social interaction."

Riesenhuber adds that there is huge variation in the ability of individuals diagnosed with autism to discriminate faces, and that some autistic people have no problem with facial recognition.

"But for those that do have this challenge, it can have substantial ramifications -- some researchers believe deficits in face processing are at the root of social dysfunction in autism," he says.

The neural basis for face processing
Neuroscientists have used traditional fMRI studies in the past to probe the neural bases of behavioral differences in people with autism, but these studies have produced conflicting results, says Riesenhuber.

"The fundamental problem with traditional fMRI techniques is that they can tell which parts of the brain become active during face processing, but they are poor at directly measuring neuronal selectivity," he says, "and it is this neuronal selectivity that predicts face processing performance, as shown in our previous studies."

To test their hypothesis that differences in neuronal selectivity in the FFA are foundational to differences in face processing abilities in autism, Riesenhuber and the study's lead author, neuroscientist Xiong Jiang, PhD, developed a novel brain imaging analysis technique, termed local regional heterogeneity, to estimate neuronal selectivity.

Read the full article here 

The above story is reprinted from materials provided by Georgetown University Medical Center

BiPolar Disorder: Cannabis increases neuro-cognitive performance

According to a study published online in the journal Psychiatry Research, individuals with bipolar disorder who used cannabis showed higher neuro-cognitive performance than patients who did not use cannabis.

The Researchers; The Zucker Hillside Hospital in Long Island, NY, in collaboration with a team at the Mount Sinai School of Medicine and the Albert Einstein College of Medicine in New York City.

They examined the difference in cognitive performance among 50 individuals with bipolar disorder who had a history of cannabis use, with 150 bipolar patients who had no history of cannabis use.

Both groups of patients were similar in age at bipolar onset. In addition, the groups did not differ in racial background, age, or highest education level achieved.

The team discovered that patients who used cannabis showed superior neuro-cognitive performance than those who did not. However, patients who used cannabis did not differ considerably on estimates of premorbid IQ.

The researchers explained: "Results from our analysis suggest that subjects with bipolar disorder and history of (cannabis use) demonstrate significantly better neurocognitive performance, particularly on measures of attention, processing speed, and working memory.

These findings are consistent with a previous study that demonstrated that bipolar subjects with history of cannabis use had superior verbal fluency performance as compared to bipolar patients without a history of cannabis use.

Similar results have also been found in schizophrenia in several studies."

They concluded, "The data could be interpreted to suggest that cannabis use may have a beneficial effect on cognitive functioning in patients with severe psychiatric disorders.

However, it is also possible that these findings may be due to the requirement for a certain level of cognitive function and related social skills in the acquisition of illicit drugs."

What is Bipolar Disorder?  
Bipolar disorder, more commonly known in the past as manic depression or manic depressive illness, is a mental disorder in which the patient has mood instability, often severe. In severe cases the illness can be very disabling, psychologically and socially.

An individual with bipolar disorder typically has unusual shifts in mood, energy, and the ability to function - these changes can last for weeks and sometimes months.

The fluctuations present in bipolar disorder are much more severe than the "ups-and-downs" we all go through. The changes are much steeper and last longer.

They can damage relationships, destroy job prospects, and undermine school performance. Some patients find their symptoms so unbearable that they attempt to commit suicide.

Medication is not a way for ADHD kids to cheat

We are students living with learning disabilities and attention deficit hyperactivity disorder. We disagree with the "Abuse of ADHD drugs creates uneven playing field" (Open Forum, March 16), which compared ADHD medication with performance-enhancing steroids in sports and asked: "Is ADHD (medication) use cheating as well?"

While the author rightly criticizes student use of any stimulant or ADHD drug by those who are not diagnosed with ADHD to enhance their performance, and points out that the drugs don't work unless one has ADHD, she suggests that drug use even by those diagnosed with ADHD somehow gives an unfair advantage.

Wrong.

Accommodations and allowing the use of medication are legally required for students with disabilities. Accommodations are like supplying ramps for wheelchairs, assistive listening devices for the hearing-impaired, glasses for those who need them, or software that reads text aloud for the blind and dyslexic.

Accommodations give students with learning disabilities and ADHD an equal opportunity to succeed in an educational environment that caters to a narrowly defined learning style. They level the playing field. They keep us in school.

Medication is no "enhancer" for us. As one of our students with ADHD put it, those who do not have ADHD "only see the drug as a drug, and nothing else.

They don't see the fight that rages on inside me, my constant struggle to focus, my inability to stay organized, and my tireless efforts to complete tasks others would view as easy." For those with ADHD, medication is a tool, not a solution.

Attending school as a student with learning disabilities or ADHD is hard enough. Fighting the stigma is even harder.

Many students, fearful of the stigma, don't seek help, don't want to be identified and are fearful of being different.

Without good support, without the right accommodations (sometimes including medication), without understanding how we learn or discovering our strengths, we fail, we drop out, and society loses out on valuable contributors.

We now know that a disproportionate number of our most successful CEOs and entrepreneurs have dyslexia or ADHD. They think outside the box; standardized education and high-stakes testing does not hinder their brilliance.

So, please: Learning disabilities, including ADHD, are real. It's really hard to be a student with learning disabilities and ADHD. It's harder yet when people talk about us, not with us.