Sunday, September 23, 2012

Normal brains, waning with age

Some elderly become vulnerable to scams. The losses can be high.

Murray Grossman, left, studies degeneration of the brain's frontal and temporal lobes at Penn.
Murray Grossman, left, studies degeneration of the brain
The patient was in his 80s. He didn't have dementia, but this smart, sophisticated man had made a series of baffling, devastatingly bad financial decisions of a sort that are all too common at his age.

He had been told he'd won a contest and would get a big prize if he sent some money in first. His daughter caught on after the man had lost "tens of thousands of dollars," said Murray Grossman, a University of Pennsylvania neurologist who studies degeneration of the brain's frontal and temporal lobes.

Even after the patient's daughter changed his phone numbers and took control of his bank account, even after he knew the contest was a scam, he tried to give the con artists more money. "The guy would literally call the scammer and give him the new phone number," Grossman said.

As far as Grossman could tell, the man had "normal" aging, which is cold comfort. Just as our muscles and eyes typically decline with age, so too do our brains. They shrink and show other signs of wear. And that process often plays disproportionate hell with the frontal lobes.

Located behind your forehead and above your eyes, the frontal lobes are the seat of what doctors call executive function - abilities that help you assess new situations, perform complex, multistep tasks, and make decisions.

Jason Karlawish, a geriatrician and bioethicist at the Penn Memory Center, said there's growing interest in changes in judgment and decision-making that go along with aging but "right now don't map onto any disease."

Last year, the FINRA Investor Education Foundation and Stanford University's Center on Longevity jointly launched the Research Center on the Prevention of Financial Fraud. The National Endowment for Financial Education met with researchers this month to lay groundwork for a project on diminished financial capacity and cognitive decline.

University of Iowa researchers recently published a study showing that people with damage in the ventromedial prefrontal cortex - a part of the frontal lobe that often degrades in the elderly - were more vulnerable to misleading advertising. A Vanderbilt University study this year traced older people's problems with making decisions in novel situations to a decline in the white matter that connects the medial prefrontal cortex with the striatum deeper in the brain.

Another group from Harvard and New York Universities and the Federal Reserve Bank and Board studied real-world decisions involving mortgages and credit cards. The quality of decisions peaked at age 53.

"This kind of research," said David Laibson, a Harvard behavioral economist and one of the authors of that study, "is . . . going to be an explosively important topic."

The obvious reason is demographics. Baby boomers are getting old. The rise in obesity and diabetes also does not bode well. Both increase the odds of dementia caused by vascular problems, which not only lead to more frontal lobe dysfunction than Alzheimer's, but also make Alzheimer's worse.

Laibson said the demise of pensions is another reason the research is important. In the old days, a con artist could steal only so much at a time. Now, older people can easily have retirement accounts with half a million dollars in them. "Boy, is that a juicy target," he said.

Laibson is worried about fraud, but he's even more concerned about bad, but legal, investments.

As scientific studies of the aging brain reveal more about how structural damage affects thinking, they raise thorny, as-yet-unanswered questions. How do we protect the vulnerable elderly? How do we make sure that aging CEOs, investment managers, and politicians can handle their demanding jobs? One researcher recommends annual cognitive tests, a slippery slope if ever there was one.

There's ample evidence that people can make stupid decisions or be victims of fraud at any age.

"All of us can be taken," said Anthony Pratkanis, a University of California Santa Cruz psychology professor who studies persuasion.

Laura Carstensen, director of Stanford's Center on Longevity, said the trick will be finding ways to safeguard the vulnerable without restricting people who can still make their own financial decisions. "There are a lot of older people who I would turn to in a heartbeat for financial advice," she said, including her 92-year-old father. Suggesting she should take over for him would be "truly offensive and ridiculously stupid."

Researchers on all sides, though, agree that older people are disproportionately targeted, in part because they have more assets.

Those who study the aging brain, however, think some older people are at special risk. About half of adults in their 80s, Laibson said, suffer from either dementia or cognitive impairment without dementia.

"People who throughout their life have not been vulnerable to scams do become vulnerable in their later years," said Daniel Marson, a neuropsychologist and lawyer who runs the University of Alabama at Birmingham's Alzheimer's Disease Center. "We think that financial abilities are exquisitely vulnerable to early cognitive changes."

Psychologists have known for decades that executive function declines with age. Some aspects peak in the 20s. Luckily, the decline is balanced by wisdom. Overall knowledge rises throughout adulthood. As Scott Huettel, a neuroscientist at Duke University, put it, older people can't respond as fast to a changing streetlight, but they're less likely to put themselves in situations where they make mistakes.

The question of what's normal and what's an early symptom of dementia has taken on more urgency as doctors have come to realize that Alzheimer's and other dementias may start decades before symptoms become disabling.

The aging brain remains a vast frontier, vulnerable to time, vascular problems that can rob it of vital energy, and errant proteins associated with Alzheimer's disease and, Grossman's specialty, frontotemporal dementia. These conditions can occur alone or together in a complex mishmash. Some of the "normal" changes doctors see may, in fact, be early signs of dementia. A recent Penn study found that the first symptoms of Alzheimer's in patients with a particular genetic profile were problems with attention, language, and executive function.

If you look at average performance on tests of what Laibson calls fluid intelligence - the ability to solve new problems - by age group, the changes are striking. The average for all age groups would be at the 50th percentile, meaning that half are above and half below. The average 20-year-old is at the 75th percentile on that scale, Laibson said. The average 80-year-old is at the 25th.

"That's just a huge change," he said.

The "normal" changes, however, are highly variable. Some 80-year-olds still have better executive function than some 20-year-olds. People with more "cognitive reserve" - typically the better-educated - can decline a fair amount before they get into trouble. Doctors suspect that everyone declines.

William Milberg, a neuropsychologist at Harvard, thinks people with high blood pressure and diabetes likely accelerate the process of deterioration by damaging blood vessels that supply the brain.

What signs indicate executive function problems?

Karlawish said doctors talk about an easy test: "Ask your older patients when was the last time they were able to organize a dinner party."

Frontal lobe damage does indeed impair organization. It also affects working memory, or the ability to hold multiple ideas in your head while you work with them. Inhibiting an extraneous thought while trying to focus on another becomes harder, as in attention deficit disorder. People with damaged frontal lobes are more likely to do risky things.

Here are some tests that people find more difficult as they age: hearing a list of numbers and then reciting them backward, saying the color of letters used to spell the name of a different color (think the letters RED written in yellow ink) or ordering the 13 digits in your phone number from smallest to largest in your head.

Frontal lobe decline can also make people more impulsive and prone to false memories. The elderly are less likely to remember where they learned something, a problem if the source was shady.

Marson cites these danger signs of diminished financial capacity: new memory lapses about bills, new disorganization of financial paperwork, trouble doing math such as figuring tips and less understanding of things like fluctuating interest rates or reverse mortgages. This is the most important one: a new interest in get-rich schemes.

The National Institute of Aging has made understanding normal aging one of its initiatives. Molly Wagster, chief of the behavioral systems neuroscience branch, is interested in how older brains compensate for some of the negative changes. The NIA has funded small pilot studies that look at whether cognitive aging can be affected by exercise, brain training, and diet.

"I don't think that this is an irreversible course that everyone is on," she said.

Connecting Autistic Behavior to Brain Function

Autism is a disorder that is well known for its complex changes in behavior -- including repeating actions over and over and having difficulty with social interactions and language. Connecting these behavioral patterns to an underlying neural deficiency is imperative for understanding what gives rise to autism, to developing better measures for diagnosing those along the Autism Spectrum Disorder and designing more effective treatments.

However, even given our significant advances in understanding how the brain works, there hasn't been evidence to tie autistic behavioral patterns together with corresponding neural functions. Until now.

A team of researchers -- including myself and colleagues from Carnegie Mellon University, the University of Pittsburgh, New York University and the Weizmann Institute of Science -- were interested in trying to understand on a basic neural level what happens inside the brain that might give rise to the altered behaviors in autism. Instead of focusing on the more complex behaviors, we set out to uncover and measure fundamental neural responses -- the patterns of brain activation in individuals with autism compared to those without.

Using an fMRI at Carnegie Mellon's Scientific Imaging and Brain Research Center, we scanned the brains of 14 adults with autism and 14 without while these individuals responded separately to visual, auditory and touch stimuli. We looked at the way the most elemental part of the brain's cortex responded to these simple stimuli.

In typical individuals, every time they saw the same visual stimulus, they had an almost identical response in the primary visual system. The stimulus drove normal visual systems in the same way time and time again. So, the question was whether we would see the same kind of consistent responses in the visual, auditory and somatosensory, or touch, cortices and within autism. It was our belief that any alteration in brain response we saw would be a very powerful indication of a major characteristic of autism.

It turns out that in all three of the primary cortices -- visual, auditory and somatosensory -- we did not see the typical response trial after trial in the individuals with autism. Instead, we saw considerable variability -- sometimes a strong response, sometimes a weak response. The fact that we did not see precise responses in autism was a really important result. It suggests that there is something fundamental that is altered in the cortical responses in autism. This variability in the brain response might also possibly explain why individuals with autism find visual stimulation, touch and sound to be so strong and overwhelming.

We know from genetic research that many of the neurobiological changes that occur in autism have to do with changes at the level of the synapse, the way that information is transmitted from one neuron to another. What these results -- that autistic adults have unreliable neural responses -- does is begin to allow us to build a bridge between the kind of genetic changes that may have given rise to autism in the first place. It cracks open a new avenue of research which has a good potential to be highly informative in understanding the connection between the neurophysiology and the behavioral patterns in autism.

While this particular study involved high functioning autistic adults and fMRI, we are now running follow-up experiments using EEG. This method which will give us even more detailed information about the neural responses and will allow us to test individuals across the autism spectrum and across different age groups so that we can gain further understanding of this unreliable neural response profile. And, because unreliable neural activity is a general property that could have a profound impact on how many brain systems function, it could underlie not only autism but a range of cognitive and social abnormalities including epilepsy and schizophrenia.

We are at the tip of a huge iceberg here; further research to fill in the details of exactly how this unreliability happens is essential for accurately diagnosing and treating autism and other disorders. At places like Carnegie Mellon University, which established a Brain, Mind and Learning initiative to build from its excellence in psychology, computer science and computation to continue to solve real world problems, these types of research projects are a priority. Our ongoing collaborations with Center for Autism Research at the University of Pittsburgh, and with ABIDE, which shares autism imaging data from top research facilities around the world, are crucial for working together to make sure we have all of the scientific resources possible to conduct high quality research.

What is Creativity? Art as a Symptom of Brain Disease

Van Gogh
We don’t normally associate creativity with brain disease, but a recent paper published in Brain suggests that maybe we should. When we think of someone affected by a serious brain disorder, we imagine deterioration and loss of function, but a surprising new study shows that some people may actually develop artistic talent as a result of their brain disorder, and that in turn, their art can tell us about the nature of their brain disorder.

This recent review by Schott brings together cases of individuals with neurological conditions, who with no previous artistic motivations suddenly become compelled to make art, and the art is good!

The authors describe a case of an epileptic man with no artistic ability who began to suffer recurring epileptic attacks in which he acted aggressively, could not speak or focus his eyes, and acted out of character. During these attacks, the patient began to draw spontaneously and compulsively, and with remarkable skill. In another case, a 68 year-old man had begun to paint at age 56 with the onset of dementia, despite never being interested in art before. In the ten years that passed after the onset of his dementia, his paintings became more and more detailed, colorful, precise and realistic, and he even began to win awards for his art.

Both these cases highlight the importance of context in understanding how art can tell us about brain disorders. The onset of uncharacteristic artistic behavior or the compulsive desire to create art where there has been no desire before might indicate an emerging neurological abnormality. Similarly, in people who already have creative ability, dramatic changes in style (e.g. from abstract to realistic) can indicate the onset or progression of brain dysfunction.

But how can these unusual events tell doctors about the patient’s underlying condition? In these and most other cases of emerging artistry, involvement of the left anterior temporal lobe appears to be crucial. The temporal lobe and frontal brain regions work together and are involved in creativity. Damage or degeneration of temporal regions can release the temporal lobe’s inhibitory influence on the frontal cortex, resulting in enhanced creativity. For example, a magnetic resonance imaging (MRI) scan of the elderly man with dementia revealed severe damage to the temporal lobe, while his frontal brain regions remained intact.

Similarly, an imbalance between left and right hemisphere activity appears to affect creativity. For example, in the case of the epileptic patient, based on his unusual behavior, neurologists deduced that the seizures were originating in the left frontal hemisphere. Depression of the dominant, logical left-brain regions during his seizure had caused the “release” of the more creative right brain, resulting in his unusual artistic ability.

These interesting case studies offer a new perspective on the way we study brain disorders, and challenge our understanding of creativity. The neural networks involved in creativity are delicately balanced. Disruption of this network can lead to the surprising and counter-intuitive emergence of new artistic talent; talent that is regarded by many to be a skill that is learned over years of practice. What makes some people artistically talented and others not? Practice or innate ability? The relevance of the age-old debate, ‘nature versus nurture?’ is brought to the fore by these cases, and points to the emergence of an exciting new, interdisciplinary field of neuroscience research.

Fast-food logos light up kids’ brains

 Fast-food logos light up kids’ brains London: The brains of children are ‘imprinted’ with logos of fast-food companies, according to a new study.

The study, conducted at the University of Missouri-Kansas City and the University of Kansas Medical Center, found that the pleasure and appetite centres of the brains light up when children are shown advertising images such as the McDonald’s logo.

But the same areas do not respond to well-known logos that are not to do with food, the Independent reported.

Scientists suggest fast-food firms are tapping into the reward areas of the brain, and that these develop before the regions that provide self-control, leading to unhealthy choices.

“Research has shown children are more likely to choose those foods with familiar logos. That is concerning because the majority of foods marketed to children are unhealthy, calorifically-dense foods high in sugars, fat, and sodium,” said Dr Amanda Bruce, who led the study.

The study selected 120 popular food and non-food brands, including McDonald’s and Rice Krispies, and BMW and FedEx.

They used a type of MRI scanner – functional magnetic resonance imaging – which homes in on changes in blood flow: when areas of the brain become more active, blood flow increases.

Scans were carried out on children aged 10 to 14 as they were exposed to 60 food and 60 non-food logos. The results showed the food logos triggered increased activity in areas of the brain known to be involved in reward processing and in driving and controlling appetite.

The finding comes in the wake of research which showed advertising had a pronounced effect on children’s eating habits. Children who tasted two identical burgers, one in a plain box and one labelled McDonald’s, preferred the latter.

It`s the brain that draws you to chocolate

It`s the brain that draws you to chocolate Washington: What makes chocolate so irresistible? Scientists have traced the lure of chocolate to a part of the brain called neostriatum, and its production of a natural, opium-like chemical, enkephalin.

The findings reveal a surprising extension of the neostriatum`s role, as Alexandra DiFeliceantonio, from the University of Michigan, Ann Arbor and her team made the discovery.

DiFeliceantonio notes that the brain region had primarily been linked to movement. And there is reason to expect that the findings in rats can tell us a lot about our own binge-eating tendencies, the jounral "Current Biology" reports.

The researchers also found that enkephalin surged when rats began to eat the candy-coated morsels, according to a Michigan statement.

It`s not that enkephalins or similar drugs make the rats like the chocolates more, the researchers say, but rather that the brain chemicals increase their desire and impulse to eat them.

"This means that the brain has more extensive systems to make individuals want to over consume rewards than previously thought," said DiFeliceantonio. "It may be one reason why over consumption is a problem today."

"The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes," she says.

"It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of over consumption and addiction in people," she said.