FASD: Prenatal alcohol exposure alters development of brain function

fMRI scan of working memory activation in typically-developing children. 

Credit: The Saban Research Institute

In the first study of its kind, Prapti Gautam, PhD, and colleagues from The Saban Research Institute of Children's Hospital Los Angeles found that children with fetal alcohol spectrum disorders (FASD) showed weaker brain activation during specific cognitive tasks than their unaffected counterparts.

These novel findings suggest a possible neural mechanism for the persistent attention problems seen in individuals with FASD.

The results of this study will be published in Cerebral Cortex on August 4.

"Functional magnetic resonance imaging (fMRI) has been used to observe brain activity during mental tasks in children with FASD, but we are the first to utilize these techniques to look at brain activation over time," says Gautam.

"We wanted to see if the differences in brain activation between children with FASD and their healthy peers were static, or if they changed as children got older."

FASD encompasses the broad spectrum of symptoms that are linked to in utero alcohol exposure, including cognitive impairment, deficits in intelligence and attention and central nervous system abnormalities.

These symptoms can lead to attention problems and higher societal and economic burdens common in individuals with FASD.

During the period of childhood and adolescence, brain function, working memory and attention performance all rapidly improve, suggesting that this is a crucial time for developing brain networks.

To study how prenatal alcohol exposure may alter this development, researchers observed a group of unaffected children and a group of children with FASD over two years.

They used fMRI to observe brain activation through mental tasks such as visuo-spatial attention, how we visually perceive the spatial relationships among objects in our environment, and working memory.

"We found that there were significant differences in development brain activation over time between the two groups, even though they did not differ in task performance," notes Elizabeth Sowell, PhD, director of the Developmental Cognitive Neuroimaging Laboratory at The Saban Research Institute and senior author on the manuscript.

"While the healthy control group showed an increase in signal intensity over time, the children with FASD showed a decrease in brain activation during visuo-spatial attention, especially in the frontal, temporal and parietal brain regions."

These results demonstrate that prenatal alcohol exposure can change how brain signaling develops during childhood and adolescence, long after the damaging effects of alcohol exposure in utero.

The atypical development of brain activation observed in children with FASD could explain the persistent problems in cognitive and behavioral function seen in this population as they mature.

Oxytocin spray improves brain function in children with autism

Spacefilling model of oxytocin. Image: Wikipedia.

A single dose of the hormone oxytocin, delivered via nasal spray, has been shown to enhance brain activity while processing social information in children with autism spectrum disorders, Yale School of Medicine researchers report in a new study published in the Dec. 2 issue of Proceedings of the National Academy of Sciences.

"This is the first study to evaluate the impact of oxytocin on brain function in children with autism spectrum disorders," said first author Ilanit Gordon, a Yale Child Study Center postdoctoral fellow, whose colleagues on the study included senior author Kevin Pelphrey, the Harris Professor in the Child Study Center, and director of the Center for Translational Developmental Neuroscience at Yale.

Gordon, Pelphrey, and their colleagues conducted a double-blind, placebo-controlled study of 17 children and adolescents with autism spectrum disorders.

The participants, between the ages of 8 and 16.5, were randomly given either oxytocin spray or a placebo nasal spray during a task involving social judgments.

Oxytocin is naturally occurring hormone produced in the brain and throughout the body.

Kevin Pelphrey

"We found that brain centers associated with reward and emotion recognition responded more during social tasks when children received oxytocin instead of the placebo," said Gordon.

"Oxytocin temporarily normalized brain regions responsible for the social deficits seen in children with autism."

Gordon said oxytocin facilitated social attunement, a process that makes the brain regions involved in social behavior and social cognition activate more for social stimuli (such as faces) and activate less for non-social stimuli (such as cars).

"Our results are particularly important considering the urgent need for treatments to target social dysfunction in autism spectrum disorders," Gordon added.

More information: "Oxytocin enhances brain function in children with autism," by Ilanit Gordon et al. www.pnas.org/cgi/doi/10.1073/pnas.1312857110

Dementia and the Late Onset of Dyslexia

Searching for Utopia

This post examines the differences between  Semantic dementia (SD), a progressive neurodegenerative disorder characterized by loss of semantic memory in both the verbal and non-verbal domains AND Semantic Aphasia (AD), a progressive neurodegenerative disorder or aphasia, characterised by the loss of recognition of the meaning of words and phrases.

The NIH paper this is taken from is very 'technical' in its form and is primarily for cognitive scientists to review and discuss but, with some effort on our part, we can see through the jargon to determine that current research is able to distinguish between the onset of Dementia and its effect on our cognitive abilities.


Below is an extract from the paper:

"This NIH study examined the impact of semantic impairment on a variety of “pre-semantic tasks” – lexical decision, object decision, colour decision, reading aloud, spelling to dictation, past tense generation and delayed picture copying – in semantic dementia (SD) and semantic aphasia (SA).

Previous research indicates that all of these tasks are affected in a highly predictable way by the semantic degradation in Semantic Dementia (see Patterson et al., 2006).

SD patients have difficulty with transformations that are atypical and make “regularisation errors” in which irregular items are produced as if they were domain-typical.

In contrast, we found that comprehension impairment in Semantic Aphasia did not result in this pattern.

1. In all seven “pre-semantic” tasks that we examined, the SA patients were less sensitive to typicality than the SD patients (producing significant group by regularity interactions), even though the two groups were matched for performance on semantic tests. 
2. In several tasks, the aphasic group were also less sensitive to item frequency and/or showed a smaller frequency by typicality interaction than the patients with SD. 
3. In production tasks, the SA patients made fewer regularisation errors and many more implausible responses than the SD group – for example, unrelated, semantic and perseverative errors.

The predicted effects of semantic impairment on pre-semantic tasks have been demonstrated most frequently in patients with SD.

In contrast, patients who show a breakdown in this association – i.e., preserved reading of irregular words despite pronounced semantic memory problems – are typically individuals with AD and stroke aphasia (Gerhand, 2001; Lambon Ralph et al., 1995).

These cases are viewed as highly significant by some researchers because they suggest that semantic memory impairment and regularisation errors on “pre-semantic” tasks are dissociable.

However, our findings indicate that strong typicality effects in “pre-semantic” tasks follow degradation of ATL semantic representations and not poor executive control of semantic cognition.

As the semantic deficit in SA and to some extent AD is likely to be related to poor executive control, individuals with these conditions do not disconfirm the hypothesis that semantic representations play an important role in “pre-semantic” cognition.

Read the full paper here at NIH website

Childhood Obstructive Sleep Apnea (OSA): Treatment reverses brain abnormalities

Treatment of obstructive sleep apnea (OSA) in children normalizes disturbances in the neuronal network responsible for attention and executive function, according to a new study.

“OSA is known to be associated with deficits in attention, cognition, and executive function,” said lead author Ann Halbower, MD, Associate Professor at the Children’s Hospital Sleep Center and University of Colorado Denver.

“Our study is the first to show that treatment of OSA in children can reverse neuronal brain injury, correlated with improvements in attention and verbal memory in these patients.”

The results will be presented at the ATS 2012 International Conference in San Francisco.

In the study, children (ages 8-11) with moderate-severe OSA were compared to healthy controls.

Brain imaging with magnetic resonance spectroscopy imaging was performed at baseline in 15 OSA patients and seven controls, along with neuro-psychological testing.

OSA treatment consisted of adenotonsillectomy followed by monitored continuous positive airway pressure (CPAP) or nasal treatments. Brain imaging and neuropsychological testing was performed again in 11 OSA patients and the seven controls six months after treatment.

Compared with controls at baseline, children with OSA exhibited significantly decreased N-acetyl aspartate to choline ratios (NAA/Cho) in the left hippocampus and left frontal cortex, along with significant decreases in the executive functions of verbal memory, and attention.

Following treatment, both left and right frontal cortex neuronal metabolites normalized, and hippocampal metabolites improved with a medium effect size (0.5).

More complete reversal of hippocampal abnormalities was seen in children with milder OSA when apnea-hypopnea index (AHI) improved (although this is very preliminary data).

Verbal memory and attention improved with medium to large effect sizes. Improvements in attention and verbal memory were correlated with normalization of NAA/Cho in the right and left frontal cortex (p=0.5).

“We have demonstrated for the first time that treatment of OSA in children normalizes brain metabolites in portions of the neuronal network responsible for attention and executive function,” concluded Dr. Halbower.

“We speculate that if OSA is treated earlier, there may be a more brisk improvement in the hippocampus, a relay station for executive function, learning, and memory.”

“Our results point to the importance of early diagnosis and treatment of OSA in children, as it could potentially have profound effects on their development.”

Dyslexia: 50 years old dyslexic man says "my life is a living hell"

This is a video response to a comment left under Dyslexic Brian's My Dyslexia Life Story video.

It is understandable that dyslexia can have such a negative impact on a person's life especially if they are struggling to understand and overcome it fully.

Dyslexia need not destroy your life. We all have much to do and need to reach out more.

Check out more at DyslexicBrian.com

Prosopagnosia - Face Blidness

Prosopagnosia is a disorder of face perception where the ability to recognize faces is impaired, while the ability to recognize other objects may be relatively intact.

The term originally referred to a condition following acute brain damage, but a congenital form of the disorder has been proposed, which may be inherited by about 2.5% of the population.

The specific brain area usually associated with prosopagnosia is the fusiform gyrus.

Few successful therapies have so far been developed for affected people, although individuals often learn to use 'piecemeal' or 'feature by feature' recognition strategies.

This may involve secondary clues such as clothing, gait, hair colour, body shape, and voice. Because the face seems to function as an important identifying feature in memory, it can also be difficult for people with this condition to keep track of information about people, and socialize normally with others.

Some also use the term prosophenosia, which refers to the inability to recognize faces following extensive damage of both occipital and temporal lobes.

Children with Prosopagnosia
Developmental prosopagnosia can be a difficult thing for a child to both understand and cope with. Many adults with developmental prosopagnosia report for a long time they had no idea that they had a deficit in face processing, unaware that others could distinguish people solely on facial differences.

Children with prosopagnosia can be hard to find. They may just appear to be very shy or slightly odd due to their inabilities to recognise faces.

Children with prosopagnosia may have a hard time making friends, as they may not recognize their classmates. They often make friends with children with other distinguishing features.

Children with prosopagnosia may also have difficulties following the plots of television shows and movies, as they have trouble recognizing the different characters.

They tend to gravitate towards cartoons, where the characters always wear the same thing and have other distinguishing features.

Prosopagnosiac children may also have a hard time telling family members apart or recognizing people out of context (i.e. the teacher in a grocery store).

Additionally, those children with prosopagnosia can have a difficult time with the public school system, as many school professionals are not well versed in prosopagnosia, if they are aware of the disorder at all.

Resources
Resources to help parents and professionals cope with prosopagnosia in children are also being developed, such as Understanding Facial Recognition Disorders in Children by Nancy L. Mindick

Oliver Sacks, famous neuroscientist, author of many books including The Man Who Mistook His Wife for a Hat; although he knew what prosopagnosia was and had studied it, he did not realise he had it until people became shocked that he confused one of his brothers with the other and then, discussing it with family members, learned that a number of them had similar difficulties with face.

Dame Jane Goodall, British primatologist, ethologist, and anthropologist, best known for her 45-year study of social and family interactions of wild chimpanzees.

Listen to Jane describe her condition and how it's affected her life:

Dyslexic Brian: Pav's home page video - YouTube

Dyslexia:Synesthesia can improve Memory, Reading and Spelling

We investigated whether functional brain networks are different in coloured-hearing synaesthetes compared with non-synaesthetes.

Based on resting state electroencephalographic (EEG) activity, graph-theoretical analysis was applied to functional connectivity data obtained from different frequency bands (theta, alpha1, alpha2, and beta) of 12 coloured-hearing synaesthetes and 13 non-synaesthetes.

The analysis of functional connectivity was based on estimated intra-cerebral sources of brain activation using standardized low-resolution electrical tomography.

These intra-cerebral sources of brain activity were subjected to graph-theoretical analysis yielding measures representing small-world network characteristics (cluster coefficients and path length).

In addition, brain regions with strong interconnections were identified (so-called hubs), and the interconnectedness of these hubs were quantified using degree as a measure of connectedness.

Our analysis was guided by the two-stage model proposed by Hubbard and Ramachandran (2005).

In this model, the parietal lobe is thought to play a pivotal role in binding together the synaesthetic perceptions (hyperbinding).

In addition, we hypothesized that the auditory cortex and the fusiform gyrus would qualify as strong hubs in synaesthetes.

Although synaesthetes and non-synaesthetes demonstrated a similar small-world network topology, the parietal lobe turned out to be a stronger hub in synaesthetes than in non-synaesthetes supporting the two-stage model.

The auditory cortex was also identified as a strong hub in these coloured-hearing synaesthetes (for the alpha2 band).

Thus, our a priori hypotheses receive strong support. Several additional hubs (for which no a priori hypothesis has been formulated) were found to be different in terms of the degree measure in synaesthetes, with synaesthetes demonstrating stronger degree measures indicating stronger interconnectedness.

These hubs were found in brain areas known to be involved in controlling memory processes (alpha1: hippocampus and retrosplenial area), executive functions (alpha1 and alpha2: ventrolateral prefrontal cortex; theta: inferior frontal cortex), and the generation of perceptions (theta: extrastriate cortex; beta: subcentral area).

Taken together this graph-theoretical analysis of the resting state EEG supports the two-stage model in demonstrating that the left-sided parietal lobe is a strong hub region, which is stronger functionally interconnected in synaesthetes than in non-synaesthetes.

The right-sided auditory cortex is also a strong hub supporting the idea that coloured-hearing synaesthetes demonstrate a specific auditory cortex.

A further important point is that these hub regions are even differently operating at rest supporting the idea that these hub characteristics are predetermining factors of coloured-hearing synaesthesia.

The DOI Paper: DOI: 10.1111/j.1748-6653.2011.02004.x

View Full Article (HTML) Get PDF (253K)

SAD: Take your light therapy, and stick it in your ear

Many readers in the Northern Hemisphere are likely already starting to experience seasonal affective disorder, appropriately enough known as SAD.

For those people fortunate enough not to be familiar with it, SAD is a mood disorder that is brought on by the shorter day-length experienced in winter - less sunlight results in gloomier people.

One of the most common treatments involves regular exposure to bright artificial lights, that appear to psychologically serve the same purpose as sunlight.

Now, one might assume that such light therapy would require that people see the light. According to the Finnish designers of the Valkee device, however, light also does the trick if you shine it up your ears.

The invention is based around the assertion that not only are our visual systems photosensitive, but so are our brains themselves.

More specifically, there are apparently 18 sites in our brains, where OPN3 photoreceptor proteins are located. These regions will supposedly react favourably to exposure to light, even when that light is filtered through tissue and bone.

The Valkee itself looks a lot like a personal music player, complete with earbuds. Instead of emitting music, however, these buds contain fiber optic lights.

By turning the device on and sticking the glowing fibers in your ears for about ten minutes a day, it is claimed that your brain will receive enough light to send the SAD packing.

Does it sound like quackery? A great deal of people would certainly say so.

Not among those people, however, would be a group of scientists from Finland's University of Oulu.

In two clinical trials, they had people with severe SAD use the device daily, for 8 to 12 minutes a day.

Afterward, when those people completed a BDI-21 questionnaire (a standard for assessing depression), it was found that 92 percent of the subjects in the first trial had completely recovered.

The information presented by the company is definitely somewhat difficult to sort out, although it appears that the results of the second trial were similarly encouraging.

A placebo group was included in at least one of the trials, to ensure that people weren't feeling better merely because they expected to.

To read more about the Valkee device visit their website

Brain Scans Reveal Lucid Dreaming's 'Sleep Cinema'

Researchers at the Max Planck Institute of Psychiatry in Munich, Germany were recently singing their own sweet ode to lucid dreaming, albeit to the tune of the scientific method.

Led by Dr. Micael Czisch, for the first time ever, researchers were able to compare brain activity of lucid dreamers as they consciously entertained the same thoughts while sleeping and while awake.

Lucid dreamers are those who, besides being actively aware of their dream state while sleeping, can also deliberately manipulate their dreams -- a learned skill that is very useful in dream research.

"The main obstacle in studying specific dream content is that spontaneous dream activity cannot be experimentally controlled, as subjects typically cannot perform pre-decided mental actions during sleep," study researcher Michael Czisch said according to LiveScience. "Employing the skill of lucid dreaming can help to overcome these obstacles."

For the study, six lucid dreamers were asked to sleep in a functional magnetic resonance imaging (fMRI) machine so blood flow to regions of their brain could be monitored. Once asleep, subjects were asked to confirm their lucid dream-state with a series of of eye movements. They were then asked to purposely "dream" that they were clenching their fists.

Researchers found that brain activity during the lucid dreaming of this task was similar to brain activity of the same task performed while subjects were awake. However, brain activity during sleep was weaker.

The team, which also included scientists from the Charite hospital in Berlin and the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, also found increased activity in parts of the brain that play a vital role in the planning of movements.

“Our dreams are therefore not a ‘sleep cinema’ in which we merely observe an event passively, but involve activity in the regions of the brain that are relevant to the dream content,” explained Czisch

Dr Ron Minson: Integrated Listening

Ron Minson, MD had tried all the educational/medical solutions available and was still not able to help their daughter overcome the depression which resulted from a lifetime of dyslexia.

Dr. Minson’s background was traditional medicine– but the urgency of the situation led him to try something new.

The therapy showed signs of success within weeks and by the end of the 3-month program his daughter’s reading and organizational abilities had improved significantly.

More importantly, the depression which had held her back for years finally lifted

Based on clinically proven outcomes, iLs programs strengthen existing pathways and create new neural connections/pathways in the brain (“neuroplasticity”).

As these neurological connections grow stronger, language skills and emotional/psychological functions, such as self-confidence and regulation, also tend to improve.

The improvements in brain function are based on the premise that our higher brain functions – the “cortical functions” such as language, cognitive skills, socialization – rely and depend upon how well sensory input is received and processed as it enters the central nervous system and is relayed to the upper brain. iLs improves processing at both the sub-cortical and cortical levels.

iLs has a global effect on the brain and central nervous system, influencing the following systems: balance, visual, auditory, motor, coordination, behavior and emotional regulation. As a result, it is successfully implemented for a wide variety of conditions:

• Learning difficulties such as reading, spelling, math, auditory processing and attention
• Sensory processing and integration
• Stress, sleep, emotional regulation and mood problems
• Those with autism and neuro-developmental difficulties

Find out more about ILS here on their website

ADHD: Brain scans reveal drugs' effects on attention

Scientists have developed a way to use PET scans to test if drugs are helping mice that have been genetically engineered to have a form of attention deficit.

In the brain of the altered mouse (right), low dopamine levels result in a brighter image. 

(Credit: David Gutmann, MD, PhD)

Scientists have developed a way to evaluate new treatments for some forms of attention deficit disorder.

Working in mice, researchers at Washington University School of Medicine in St. Louis showed that they can use brain scans to quickly test whether drugs increase levels of a brain chemical known as dopamine.

In a study published last year, the same group found that raising dopamine levels in mice alleviates attention deficits caused by neurofibromatosis type 1 (NF1), a condition that affects more than 100,000 people in the United States. Approximately 60 percent to 80 percent of children with NF1 have some type of attention deficit problem.

"Many kids with NF1 really struggle in school, and finding ways to help alleviate attention problems is a high priority," says David H. Gutmann, MD, PhD, the Donald O. Schnuck Family Professor of Neurology.

"The technique we've refined may make it possible to match specific treatments to the patients with NF1 and attention deficit who are most likely to benefit from those treatments."

The results appear online in Experimental Neurology.

Symptoms of NF1-related attention deficits are similar to those that affect children in the general population. But it's unclear whether the brain changes that underlie these problems in children with NF1 are similar to the brain changes that cause attention deficits in the general population.

"This mouse model may not be a perfect model for all forms of attention deficit, but it is a terrific model for one type of attention system dysfunction," Gutmann says. "Greater understanding of what goes wrong in some children with NF1 could lead to new insights into a broader variety of attention problems."

Gutmann is director of the Washington University Neurofibromatosis (NF) Center, a national referral center for patients with all forms of neurofibromatosis. The center is active in basic science research and clinical trials, with the goal of developing innovative new approaches for treating patients with NF.

Gutmann and his colleagues have developed genetically engineered mice that develop NF1-related attention problems and brain tumours.

Last year, Gutmann showed that one of these lines of mice had lower levels of dopamine in part of the brain. Following treatment with the drug Ritalin, both the brain dopamine levels and the attention deficits in these mice were restored to normal.

"Prior to our study, there was no molecular basis for using Ritalin to treat children with NF1 and attention deficits, so its use depended on the pediatrician's practice, the severity of the attention deficit and how comfortable the parents were with the use of medication," Gutmann says.

"In general, only the most severely affected kids are being treated, but that may change in the future."

Read more at Science Daily

The Definition of 'Learning Disability' differs in US and UK

In the United States and Canada, the term learning disability is used to refer to psychological and neurological conditions that affect a person's communicative capacities and potential to be taught effectively.

The term includes such conditions as dysgraphia (writing disorder), dyslexia (reading disorder), dyscalculia (mathematics disorder) and developmental aphasia.In the United Kingdom, the term learning disability is used more generally to refer to developmental disability.

Someone with a learning disability does not necessarily have low or high intelligence, nor any innate inability to learn.

It just means this individual has an impairment to their ability due to a processing disorder, such as auditory processing or visual processing, that is detrimental to learning from traditional teaching methods.

Learning disabilities are usually identified by school psychologists through testing of intelligence, academics and processes of learning.

For more information about the topic Learning disability, read the full article at Wikipedia.org, or see the following related articles:

Mental retardation — Mental retardation is a term for a pattern of persistently slow learning of basic motor and language skills ("milestones") during childhood, and a ...  > read more

Dyslexia — Developmental dyslexia is a condition or learning disability which causes difficulty with reading and writing. Its standard definition is a ...  > read more

Special education — Special education, describes an educational alternative that focuses on the teaching of students with academic, behavioral, health, or physical needs ...  > read more

Brain damage — Brain damage or brain injury is the destruction or degeneration of brain cells. Brain damage may occur due to a wide range of conditions, illnesses, ...  > read more

Why Current In-the-Ear Hearing Aids Fail

Hearing aids have improved greatly over recent years, but they continue to be a surprisingly frustrating experience for new wearers.

Clearly, today’s hearing aids are tiny, nearly invisible in fact, and they amplify sound and are able to present a higher range of frequencies, but they have not yet completely solved the problem of amplifying the peripheral sounds we just don’t want, or don't need to hear.

For new wearers the crumpling of a paper bag on the other side of a room can sound like a jackhammer.

This is a huge challenge for technology because it is dependent on how the brain perceives sound and how we have learned to filter peripheral sound out of normal hearing. Andrew J. Oxenham is a psychologist and hearing expert at the University of Minnesota and an expert in psychoacoustics.

Oxenham explains: The ear works by analysing sound and breaking it into different frequencies and with many forms of hearing impairment it’s this frequency selectivity that is impaired.

What that means is that the ear doesn’t filter as well as it did before. So instead of having very sharp tuning to filter out different frequencies the filtering becomes much broader and there is no real way of compensating for that.

You can’t sharpen the filters or you can’t pre-process sound so it’s sharp. It’s like a broken TV set. You can process the signal going into the TV as much as you like but you still won’t get a clear picture of the output.

Recent hearing aids have made a lot of progress, like being able to present frequencies of up to 6000 Hz as opposed to limited frequencies up to about 4000 Hz, by using digital signal processing, and a lot more computing power on a lot smaller chip.

Another big leap forward has been made with directional hearing. They can focus the microphones toward the front and filter out a lot of the sound coming from the side and back. And although that is a fairly simple technique, it involves signal processing that wasn’t possible with earlier hearing aids.

Ambient or peripheral sound is horribly distracting for hearing aid wearers. A paper bag being crumpled across a room sounds screechingly loud.

This is common complaint of people who recently start wearing a hearing aid. Their hearing has deteriorated, often without them being completely aware of it, over a period of time.

When they are suddenly fitted with a hearing aid, they hear sounds they’ve got used to not hearing. The sounds are suddenly annoying and distracting. It’s a contrast effect.

It’s more to do with perception i.e the brain’s ability to analyse and prioritise different sounds.

It’s a complex interaction between the ear and the brain. The ear sends signals up to the brain; the brain does an awful lot of processing on top of that; then sends signals back down to the ear. These signals change the way the ear accepts input.

This is partly why hearing aids are not perfect because the hearing aid is not part of that natural feedback loop. There’s no way with current aids that the brain can interface with a hearing aid directly to change its characteristics.

Hearing Loops
To deal with background noise there are things called “hearing loops.”

These are systems that are set up within places like concert halls and churches that interface directly with the hearing aid. It’s like sending a radio signal to the hearing device.

The idea is that this hearing loop picks up the sound directly from the microphone in front of a speaker.

If you are in a conference and the speaker is talking into a microphone. Normally we hear the sound acoustically through the airwaves.

If you are wearing a regular hearing aid the microphone will pick up the sounds on the airwaves but that is together with all the background noise and reverberation in the room.

With a hearing loop it sends the signal directly from the microphone to the ear and bypasses all the acoustics in the building itself. So the ear is getting a much better, clearer and cleaner signal of what’s coming into the microphone.

Two hearing aids better than One?
It’s only recently that people have routinely been fitted with two hearing aids. Often people only got one.

Directional hearing and the way we localise sound: To know where the sound is coming from the brain compares the signals coming into the two ears. So if it’s slightly louder on one side then the brain knows the sound is coming from that side.

More importantly it’s the time of arrival difference between the two ears. If you think about a sound coming from the right. The sound will reach your right ear a little bit before it reaches your left ear.

Although we are talking about millionths of seconds, your brain needs two ears to make a distinction. If you only have one you lose that ability to localise sound and tell which direction it is coming from.

It’s also an important part of filtering out sound and noise. The brain can determine if there is speech right in front and background noise in back of and to the side. The brain can use those differences in localisation to help to make the speech more intelligible.

So the biggest technical challenge is developing hearing aids that can focus on what we really need and want to listen to. This is the current problem.

The Solution
We are hoping through even more sophisticated signal processing schemes that we’ll be able to work on artificial source segregation; i.e. analysing the signal that is coming in and figuring out what is speech and what isn’t, and only presenting to the ear the wanted signal.

Distinguishing between speech and noise
The assumption is that what you really want to listen to is speech, and so there are certain acoustical aspects of speech that we can recognise and there are certain acoustical aspects of noise that are different from speech.

So, we need to establish a suitable algorithm to be able to distinguish between speech and noise that will help you towards filtering the unwanted signal.

A more complete solutiion could mean that brain-computer interface may be part of the hearing aid systems of the future. Where the hearing aid is tapping into brain responses to pick up the specific signal the person wants to pay attention to.

This is an ongoing process with incremental steps and we will continue to see improvements over the next 15 years.

How Children Learn to Read - Book Review

This book brings together in one volume information about the neurobiological, genetic, and behavioral bases of reading and reading disabilities.

In recent years, research on assessment and treatment of reading disability (dyslexia) has become a magnet for the application of new techniques and technologies from neuroscience, cognitive psychology, and cognitive neuroscience.

This interdisciplinary fusion has yielded numerous and diverse findings regarding the brain basis of this syndrome, which are discussed in this volume by leading researchers.

Intervention approaches based on such research are presented. The book also calls for research in specific directions, to encourage the field to continue moving into the bold frontier of how the brain reads.

The volume is essential reading for a range of researchers, clinicians, and other professionals interested in reading and reading disability, and also commemorates the tenth anniversary of the Extraordinary Brain Conferences hosted by The Dyslexia Foundation.

Table of Contents

W. Baker, Preface. P. McCardle, N. Landi, K. Pugh, Introduction.


Section 1. Major Themes in the Study of the Neurobiology of Dyslexia. S. Frost, R. Sandak, W.E. Mencl, N. Landi, J.G. Rueckl, L. Katz, K. Pugh, Mapping the Word Reading Circuitry in Skilled and Disabled Readers. G. Rosen, Y. Wang, C.G. Fiondella, J.J. Lo Turco, The Brain and Developmental Dyslexia: Genes, Anatomy, and Behavior. G. Sherman, C. Cowen, From Research Lab to School Front Lines: Talents and Dilemmas in Children with Learning Differences.


Section 2. Methods and Tools. D. Francis, Methodological Advances in Developmental Research. E. Mencl, S. Frost, K. Pugh, Tools for Multimodal Imaging. J. Rueckl, M. Seidenberg, Computational Modeling and the Neural Bases of Reading and Reading Disorders. E. Grigorenko, A.J. Naples, The Devil is in the Details: Decoding the Genetics of Reading.


Section 3. Neurobiological, Genetic, and Cognitive Aspects. F. Ramus, G. Szenkovits, Understanding the Nature of the Phonological Deficit. P. Cornelissen, Visual Word Recognition: Insights from MEG and Implications for Developmental Dyslexia. L.E. Cutting, S.H. Eason, K. Young, A.L. Alberstadt, Reading Comprehension: Cognition and Neuroimaging. R. Olson, B. Byrne, S. Samuelsson, Reconciling Strong Genetic and Strong Environmental Influences on Individual Differences and Deficits in Reading Ability. R. Frost, Reading in Hebrew vs. Reading in English: Is there a Qualitative Difference?


Section 4. Intervention. B. Foorman, S. Al Otaiba, Reading Remediation: State of the Art. L. Siegel, Remediation of Reading Difficulties in English Language Learning Students. M. Wolf, S. Gottwald, W. Galante, E. Norton, L. Miller, How the Origins of Reading Instruct our Knowledge of Reading Development and its Intervention. P. McCardle, K. Pugh, Integration of Methodologies in Cognitive Neuroscience: Research Planning and Policy.

Reviews

"This volume is a valuable contribution to our growing understanding of the biological and cognitive bases of dyslexia. We believe that researchers in neuroscience, genetics, and cognitive science will find useful summaries of current research in these areas. 

Reading instructors looking for current research that is relevant to the development of intervention programs will find the volume challenging but rewarding." – David W. Carroll and Debora P. Carroll in PsycCRITIQUES

Speaking and Understanding Speech Share the Same Parts of the Brain

The brain has two big tasks related to speech: making it and understanding it.

Psychologists and others who study the brain have debated whether these are really two separate tasks or whether they both use the same regions of the brain.

Now, a new study, published in the August issue of Psychological Science, a journal of the Association for Psychological Science, finds that speaking and understanding speech share the same parts of the brain, with one difference: we don't need the brain regions that control the movements of lips, teeth, and so on to understand speech.

Most studies of how speech works in the brain focuses on comprehension. That's mostly because it's easier to image the brains of people who are listening quietly; talking makes the head move, which is a problem when you're measuring the brain.

But now, the Donders Institute at the Radboud University Nijmegen, where the study was conducted, has developed technology that allows recording from a moving brain.

Laura Menenti, a Postdoctoral Research Associate at the University of Glasgow, co-wrote the paper along with Peter Hagoort of Radboud University Nijmegen and the Max Planck Institute for Psycholinguistics, Sarah Gierhan and Katrien Segaert.

Menenti was initially interested in how the brain produces grammatical sentences and wanted to track the process of producing a sentence in its entirety; looking not only at its grammatical structure but also at its meaning.

"What made this particularly exciting to us was that no one had managed to perform such a study before, meaning that we could explore an almost completely new topic," says Menenti.

The authors used functional MRI technology to measure brain activity in people who were either listening to sentences or speaking sentences.

The other problem with measuring brain activity in people who are speaking is that you have to get them to say the right kind of sentence.

The authors accomplished this with a picture of an action -- a man strangling a woman, say -- with one person coloured green and one coloured red to indicate their order in the sentence.

This prompted people to say either "The man is strangling the woman" or "The woman is strangled by the man." (The experiments were all carried out in Dutch.)

From this, the researchers were able to tell where in the brain three different speech tasks (computing meaning, coming up with the words, and building a grammatical sentence) -- were taking place.

They found that the same areas were activated for each of these tasks in people who were speaking and people who were listening to sentences.

However, although some studies have suggested that while people are listening to speech, they silently articulate the words in order to understand them, the authors found no involvement of motor regions when people were listening.

According to Menenti, though the study was largely designed to answer a specific theoretical question, it also points towards some useful avenues for treatment of people with language-related problems.

It suggests that while it sometimes seems that people with comprehension problems may have intact production, and vice versa, this may not necessarily be the case. According to Menenti, "Our data suggest that these problems would be expected to always at least partly coincide.

On the other, our data confirm the idea that many different processes in the language system, such as understanding meaning or grammar, can at least partly, be damaged independently of each other."

Profound reorganisation in brains of adults who stutter

Hearing Beethoven while reciting Shakespeare can suppress even a King's stutter, as recently illustrated in the movie "The King's Speech."

This dramatic but short-lived effect of hiding the sound of one's own speech indicates that the integration of hearing and motor functions plays some role in the fluency (or dysfluency) of speech.

New research has shown that in adults who have stuttered since childhood, the processes of auditory-motor integration are indeed located in a different part of the brain to those in adults who do not stutter.

The findings are reported in the September 2011 issue of Elsevier's Cortex.

Dr. Nicole Neef and Dr. Martin Sommer from the University of Goettingen, together with Dr. Bettina Pollok from the University of Duesseldorf, studied the performance of a group of adults who stutter, as well as a control group of adults who do not stutter, in a finger tapping exercise.

They used Transcranial Magnetic Stimulation (TMS) to interfere temporarily with brain activity in the dorsolateral premotor cortex while the participants tapped their fingers in time with the clicks of a metronome.

In control subjects, disturbing the left premotor cortex impaired the finger tapping, but disturbing the right premotor cortex had no effect. In stuttering adults, the pattern was reversed: the accuracy of finger tapping was affected by disturbing the right hemisphere, and unaffected when disturbing the left.

Previous research has already linked stuttering with a right-shifted cerebral blood flow in the motor and premotor areas during speech. In this new study, a shift of auditory-motor integration to the right side of the brain occurred even in a task not directly involving speech.

Thus, in the brains of adults who stutter there appears to be a profound reorganisation possibly compensating for subtle white matter disturbances in other parts of the brain -- the left inferior frontal regions. These findings shed light on the extent of the reorganisation of brain functions in persistent developmental stuttering.

Profound reorganization in brains of adults who stutter: Auditory-motor integration located in different part of brain

Technique for Letting Brain Talk to Computers Now Tunes into Speech

The act of mind reading is something usually reserved for science-fiction movies but researchers in America have used a technique, usually associated with identifying epilepsy, for the first time to show that a computer can listen to our thoughts.


In a new study, scientists from Washington University demonstrated that humans can control a cursor on a computer screen using words spoken out loud and in their head, holding huge applications for patients who may have lost their speech through brain injury or disabled patients with limited movement.

By directly connecting the patient's brain to a computer, the researchers showed that the computer could be controlled with up to 90% accuracy even when no prior training was given.

Patients with a temporary surgical implant have used regions of the brain that control speech to "talk" to a computer for the first time, manipulating a cursor on a computer screen simply by saying or thinking of a particular sound.

"There are many directions we could take this, including development of technology to restore communication for patients who have lost speech due to brain injury or damage to their vocal cords or airway," says author Eric C. Leuthardt, MD, of Washington University School of Medicine in St. Louis.

Scientists have typically programmed the temporary implants, known as brain-computer interfaces, to detect activity in the brain's motor networks, which control muscle movements.

"That makes sense when you're trying to use these devices to restore lost mobility -- the user can potentially engage the implant to move a robotic arm through the same brain areas he or she once used to move an arm disabled by injury," says Leuthardt, assistant professor of neurosurgery, of biomedical engineering and of neurobiology, "But that has the potential to be inefficient for restoration of a loss of communication."

Patients might be able to learn to think about moving their arms in a particular way to say hello via a computer speaker, Leuthardt explains. But it would be much easier if they could say hello by using the same brain areas they once engaged to use their own voices.

Read more of the article here

The research appears April 7 in The Journal of Neural Engineering. This Journal contains many free articles that help scientists, clinicians and engineers understand, replace, repair and enhance the nervous system.

Brain Training using MRI Scans: See yourself Think

As humans face increasing distractions in their personal and professional lives, University of British Columbia researchers have discovered that people can gain greater control over their thoughts with real-time brain feedback.

The study is the world's first investigation of how real-time functional Magnetic Resonance Imaging (fMRI) feedback from the brain region responsible for higher-order thoughts, including introspection, affects our ability to control these thoughts. The researchers find that real-time brain feedback significantly improves people's ability to control their thoughts and effectively 'train their brains.'

"Just like athletes in training benefit from a coach's guidance, feedback from our brain can help us to be more aware of our thoughts," says co-author Prof. Kalina Christoff, UBC Dept. of Psychology. "Our findings suggest that the ability to control our thinking improves when we know how the corresponding area in our brain is behaving."

People control thoughts better when they see their brain activity

Prosopagnosia: A Podcast with Oliver Sacks

A NEUROLOGIST’S NOTEBOOK is about prosopagnosia, or the inability to recognise faces and places. The writer describes his own difficulties recognising and remembering faces. He also has the same difficulty with places and often becomes lost when he strays from familiar routes.

At the age of seventy-seven, despite a lifetime of trying to compensate, he has no less trouble with faces and places than when he was younger. He is particularly thrown when seeing a person out of context, even if he was with that person five minutes before.

The writer gives several examples of his inability to recognize familiar people out of context, including his therapist and his assistant. After learning that his brother suffered from the same problem, the writer came to believe that they both had a specific trait, a so-called prosopagnosia, probably with a distinctive genetic basis.

He mentions several other people who have the same trait, including Jane Goodall and the artist Chuck Close. Face recognition is crucially important for humans, and the vast majority of us are able to identify thousands of faces individually, or to easily pick out familiar faces in a crowd.

People with prosopagnosia need to be resourceful and /or inventive in finding strategies for circumventing their deficits: recognising people by an unusual nose or beard, or by their spectacles, or a certain type of clothing.

The Notebook describes research done on the way the brain recognises facesand tells about the work of Christopher Pallis, Charles Gross, Olivier Pascalis, Isabel Gauthier, and other scientists. Above all, the recognition of faces depends not only on the ability to parse the visual aspects of the face—its particular features and their over-all configuration—and compare them with others, but also on the ability to summon the memories, experiences, and feelings associated with that face.

The recognition of specific places or faces goes with a particular feeling, a sense of association and meaning. He also briefly discusses déjà vu and Capgras syndrome and considers the difference between acquired prosopagnosia—through trauma, stroke or Alzheimer’s —and congenital prosopagnosia.

The writer discusses the work of Ken Nakayama and Brad Duchaine, who have explored the neural basis of face and place recognition. They have also studied the psychological effects and social consequences of developmental prosopagnosia. Severe congenital prosopagnosia is estimated to affect two to two and a half per cent of the population—six to eight million people in the United States alone.

A Podcast with Oliver Sacks : The New Yorker