Older news items (pre-2010) brought over from the old website
September 2009
Tetris increases gray matter and improves brain efficiency
In a study in which 26 adolescent girls played the computer game Tetris for half an hour every day for three months, their brains compared to controls increased grey matter in Brodmann Area 6 in the left frontal lobe and BAs 22 and 38 in the left temporal lobe — areas involved in planning complex coordinated movements, and coordinating sensory information. Their brains also showed greater efficiency, but in different areas — ones associated with critical thinking, reasoning, and language, mostly in the right frontal and parietal lobes. The finding points to improved efficiency being unrelated to grey matter increases.
Haier, R.J. et al. 2009. MRI assessment of cortical thickness and functional activity changes in adolescent girls following three months of practice on a visual-spatial task. BMC Research Notes, 2, 174.
Text available at http://www.biomedcentral.com/1756-0500/2/174/abstract
http://www.eurekalert.org/pub_releases/2009-09/bc-itg090109.php
Neural changes produced by learning to read revealed
Understanding how our brain structures change as we learn to read is difficult because of the confounding with age and the learning of other skills. Studying adult learners is also problematic because in most educated societies adult illiteracy is typically the result of learning impairments or poor health. Now a new study involving 20 former guerrillas in Colombia who are learning to read for the first time as adults has found that these late-literates showed a number of significant brain differences compared to matched adult illiterates, including more white matter between various regions, and more grey matter in various left temporal and occipital regions important for recognizing letter shapes and translating letters into speech sounds and their meanings. Particularly important were connections between the left and right angular gyri in the parietal lobe. While this area has long been known as important for reading, its function turns out to have been misinterpreted — it now appears its main role is in anticipating what we will see. The findings will help in understanding the causes of dyslexia.
Carreiras, M. et al. 2009. An anatomical signature for literacy. Nature, 461 (7266), 983-986.
http://www.physorg.com/news174744233.html
August 2009
Overweight and obese elderly have smaller brains
Analysis of brain scans from 94 people in their 70s who were still "cognitively normal" five years after the scan has revealed that people with higher body mass indexes had smaller brains on average, with the frontal and temporal lobes particularly affected (specifically, in the frontal lobes, anterior cingulate gyrus, hippocampus, and thalamus, in obese people, and in the basal ganglia and corona radiate of the overweight). The brains of the 51 overweight people were, on average, 6% smaller than those of the normal-weight participants, and those of the 14 obese people were 8% smaller. To put it in more comprehensible, and dramatic terms: "The brains of overweight people looked eight years older than the brains of those who were lean, and 16 years older in obese people." However, overall brain volume did not differ between overweight and obese persons. As yet unpublished research by the same researchers indicates that exercise protects these same brain regions: "The most strenuous kind of exercise can save about the same amount of brain tissue that is lost in the obese."
Raji, C.A. et al. 2009. Brain structure and obesity. Human Brain Mapping, Published Online: Aug 6 2009
http://www.newscientist.com/article/mg20327222.400-expanding-waistlines-may-cause-shrinking-brains
April 2009
Object recognition fast and early in processing
We see through our eye and with our brain. Visual information flows from the retina through a hierarchy of visual areas in the brain until it reaches the temporal lobe, which is ultimately responsible for our visual perceptions, and also sends information back along the line, solidifying perception. This much we know, but how much processing goes on at each stage, and how important feedback is compared to ‘feedforward’, is still under exploration. A new study involving children about to undergo surgery for epilepsy (using invasive electrode techniques) reveals that feedback from the ‘smart’ temporal lobe is less important than we thought, that the brain can recognize objects under a variety of conditions very rapidly, at a very early processing stage. It appears that certain areas of the visual cortex selectively respond to specific categories of objects.
Liu, H. et al. 2009. Timing, Timing, Timing: Fast Decoding of Object Information from Intracranial Field Potentials in Human Visual Cortex. Neuron, 62 (2), 281-290.
http://www.sciencedaily.com/releases/2009/04/090429132231.htm
http://www.eurekalert.org/pub_releases/2009-04/chb-aga042709.php
Research suggests words are seen as units and processed quickly
What exactly is going on in our brain when we read? Two new studies suggest the process is quicker and more direct than we thought. One study revealed that a region of the brain in the fusiform gyrus called the visual word form area (VWFA) recognizes words as whole units rather than letter by letter – words that differed in only one letter (e.g., "farm" and "form") produced changes in brain activity that were as profound as between completely different words (e.g., "farm" and "coat"), while incremental changes occurred in response to single-letter changes in made-up words. In another study, it was revealed that, rather than processing words in a slow, hierarchical way, we seem to process words quickly, through direct connections between visual and speech-processing systems. The first area to respond to text was the text recognition area in the occipito-temporal cortex, but it was followed within 15msec by both the VWFA and Broca's area (involved in speech processing). The results provide support for the idea that the brain has two rapid reading pathways (simultaneous rather than sequential): a lexical route using the VWFA and a sublexical route through Broca's area to the motor areas that control sound production (allowing us to sound out unfamiliar words).
Glezer, L.S., Jiang, X. & Riesenhuber, M. 2009. Evidence for Highly Selective Neuronal Tuning to Whole Words in the Visual Word Form Area. Neuron, 62 (2), 199-204.
Cornelissen, P.L. et al. 2009. Activation of the Left Inferior Frontal Gyrus in the First 200 ms of Reading: Evidence from Magnetoencephalography (MEG). PLoS ONE, 4(4), e5359. doi:10.1371/journal.pone.0005359
http://www.physorg.com/news160048496.html
http://www.sciencenews.org/view/generic/id/43348/title/Brain_reads_word-by-word
October 2007
Brain activity distinguishes false from true recollection
Although memory confidence and accuracy tend to be positively correlated, people sometimes remember with high confidence events that never happened. A new imaging study reveals that, in cases of high confidence, responses were associated with greater activity in the medial temporal lobe when the event really happened, but with greater activity in the frontoparietal region when the memory was false. Both of these regions are involved in event memory, but the medial temporal lobe focuses on specific facts about the event, while the fronto-parietal network is more likely to process the global gist of the event.
Kim, H. & Cabeza, R. 2007. Trusting Our Memories: Dissociating the Neural Correlates of Confidence in Veridical versus Illusory Memories. Journal of Neuroscience, 27, 12190–12197.
http://www.physorg.com/news113671556.html
September 2007
Why music training helps language
Several studies have come out in recent years suggesting that giving children music training can improve their language skills. A new study supports these findings by showing how. The latest study shows that music triggers changes in the brain stem, a very early stage in the processing pathway for both music and language. It has previously been thought that the automatic processing occurring at this level was not particularly malleable, and the strength of neuron connections there was fixed.
And in another study, researchers have found evidence for more commonality in the brain networks involved in music and language. One network, based in the temporal lobes, helps us memorize information in both language and music— for example, words and meanings in language and familiar melodies in music. The other network, based in the frontal lobes, helps us unconsciously learn and use the rules that underlie both language and music, such as the rules of syntax in sentences, and the rules of harmony in music.
Musacchia, G., Sams, M., Skoe, E. & Kraus, N. 2007. Musicians have enhanced subcortical auditory and audiovisual processing of speech and music. Proceedings of the National Academy of Sciences USA, 104, 15894-15898.
Miranda, R.A. & Ullman, M.T. 2007. Double dissociation between rules and memory in music: An event-related potential study. NeuroImage, 38 (2), 331-345.
http://www.sciam.com/article.cfm?chanID=sa003&articleID=39568C58-E7F2-99DF-32A49429C2B356CD&sc=WR_20071002 (1st)
http://www.sciencedaily.com/releases/2007/09/070926123908.htm (1st)
http://www.eurekalert.org/pub_releases/2007-09/gumc-tat092707.php (2nd)
June 2006
How does the bilingual brain distinguish between languages?
Studies of bilingual people have found that the same brain regions, particularly parts of the left temporal cortex, are similarly activated by both languages. But there must be some part of the brain that knows one language from another. A new imaging study reveals that this region is the left caudate — a finding supported by case studies of bilingual patients with damage to the left caudate, who are prone to switch languages involuntarily.
Crinion, J. et al. 2006. Language Control in the Bilingual Brain. Science, 312 (5779), 1537–1540.
http://sciencenow.sciencemag.org/cgi/content/full/2006/608/2?etoc
April 2006
Specific brain region for reading
Although a number of imaging studies have provided support for the idea that there’s a specific area of the brain that enables us to read efficiently by allowing us to process the visual image of entire words, the question is still debated — partly because the same area also seems to be involved in the recognition of other objects and partly because damage in this region has never been confined to this region alone. Now the experience of an epileptic requiring removal of a small area next to the so-called visual word-form area (VWFA) in the left occipito-temporal cortex has provided evidence of the region's importance for reading. After the operation, the patient’s ability to comprehend words was dramatically slower, and the results were consistent with him reading letter by letter. A brain scan confirmed that the VWFA no longer lit up when words were read, perhaps because the surgery severed its connection to other parts of the brain.
Gaillard, R. et. al. 2006. Direct Intracranial, fMRI, and Lesion Evidence for the Causal Role of Left Inferotemporal Cortex in Reading. Neuron, 50, 191-204.
http://sciencenow.sciencemag.org/cgi/content/full/2006/419/2?etoc
http://www.sciam.com/article.cfm?chanID=sa003&articleID=000D3A4E-A8D1-1446-9A6283414B7F0000
March 2005
How higher education protects older adults from cognitive decline
Research has indicated that higher education helps protect older adults from cognitive decline. Now an imaging study helps us understand how. The study compared adults from two age groups: 18-30, and over 65. Years of education ranged from 11 to 20 years for the younger group, and 8 to 21 for the older. Participants carried out several memory tasks while their brain was scanned. In young adults performing the memory tasks, more education was associated with less use of the frontal lobes and more use of the temporal lobes. For the older adults doing the same tasks, more education was associated with less use of the temporal lobes and more use of the frontal lobes. Previous research has indicated frontal activity is greater in old adults, compared to young; the new study suggests that this effect is related to the educational level in the older participants. The higher the education, the more likely the older adult is to recruit frontal regions, resulting in a better memory performance.
Springer, M.V., McIntosh, A.R., Winocur, G. & Grady, C.L. 2005. The Relation Between Brain Activity During Memory Tasks and Years of Education in Young and Older adults. Neuropsychology and Aging, 19 (2).
http://www.eurekalert.org/pub_releases/2005-03/apa-bi030705.php
January 2005
IQ-related brain areas may differ in men and women
An imaging study of 48 men and women between 18 and 84 years old found that, although men and women performed equally on the IQ tests, the brain structures involved in intelligence appeared distinct. Compared with women, men had more than six times the amount of intelligence-related gray matter, while women had about nine times more white matter involved in intelligence than men did. Women also had a large proportion of their IQ-related brain matter (86% of white and 84% of gray) concentrated in the frontal lobes, while men had 90% of their IQ-related gray matter distributed equally between the frontal lobes and the parietal lobes, and 82% of their IQ-related white matter in the temporal lobes. The implications of all this are not clear, but it is worth noting that the volume of gray matter can increase with learning, and is thus a product of environment as well as genes. The findings also demonstrate that no single neuroanatomical structure determines general intelligence and that different types of brain designs are capable of producing equivalent intellectual performance.
Haier, R.J., Jung, R.E., Yeo, R.A., Head, K. & Alkire, M.T. 2005. The neuroanatomy of general intelligence: sex matters. NeuroImage, In Press, Corrected Proof, Available online 16 January 2005
http://www.eurekalert.org/pub_releases/2005-01/uoc--iim012005.php
http://www.sciencedaily.com/releases/2005/01/050121100142.htm
July 2004
Intelligence based on the volume of gray matter in certain brain regions
Confirming earlier suggestions, the most comprehensive structural brain-scan study of intelligence to date supports an association between general intelligence and the volume of gray matter tissue in certain regions of the brain. Because these regions are located throughout the brain, a single "intelligence center" is unlikely. It is likely that a person's mental strengths and weaknesses depend in large part on the individual pattern of gray matter across his or her brain. Although gray matter amounts are vital to intelligence levels, only about 6% of the brain’s gray matter appears related to IQ — intelligence seems related to an efficient use of relatively few structures. The structures that are important for intelligence are the same ones implicated in memory, attention and language. There are also age differences: in middle age, more of the frontal and parietal lobes are related to IQ; less frontal and more temporal areas are related to IQ in the younger adults. Previous research has shown the regional distribution of gray matter in humans is highly heritable. The findings also challenge the recent view that intelligence may be a reflection of more subtle characteristics of the brain, such as the speed at which nerve impulses travel in the brain, or the number of neuronal connections present. It may of course be that all of these are factors.
Haier, R.J., Jung, R.E., Yeo, R.A., Head, K. & Alkire, M.T. 2004. Structural brain variation and general intelligence. Neuroimage. In press. http://dx.doi.org/10.1016/j.neuroimage.2004.04.025
http://www.sciencedaily.com/releases/2004/07/040720090419.htm
http://www.eurekalert.org/pub_releases/2004-07/uoc--hid071904.php
November 2003
Maturation of the human brain mapped
The progressive maturation of the human brain in childhood and adolescence has now been mapped. The initial overproduction of synapses in the gray matter that occurs after birth, is followed, for the most part just before puberty, with their systematic pruning. The mapping has confirmed that this maturation process occurs in different regions at different times, and has found that the normal gray matter loss begins first in the motor and sensory parts of the brain, and then slowly spreads downwards and forwards, to areas involved in spatial orientation, speech and language development, and attention (upper and lower parietal lobes), then to the areas involved in executive functioning, attention or motor coordination (frontal lobes), and finally to the areas that integrate these functions (temporal lobe). "The surprising thing is that the sequence in which the cortex matures appears to agree with regionally relevant milestones in cognitive development, and also reflects the evolutionary sequence in which brain regions were formed."
http://www.eurekalert.org/pub_releases/2003-11/sfn-smm110803.php
November 2001
Separate brain regions for living vs nonliving categories
Lobectomy patients were compared to normal control subjects on a variety of category naming and matching tasks. Patients were disproportionately impaired for naming living things relative to nonliving things. The authors argue that damage to the temporal lobe impairs lexical retrieval most strongly for living things and that the anterior temporal cortices are convergence zones particularly necessary for retrieving the names of living things.
Luckhurst,L. & Lloyd-Jones, T.J. 2001. A Selective Deficit for Living Things after Temporal Lobectomy for Relief of Epileptic Seizures. Brain and Language, 79 (2), 266-296.
Differential effects of encoding strategy on brain activity patterns
Encoding and recognition of unfamiliar faces in young adults were examined using PET imaging to determine whether different encoding strategies would lead to differences in brain activity. It was found that encoding activated a primarily ventral system including bilateral temporal and fusiform regions and left prefrontal cortices, whereas recognition activated a primarily dorsal set of regions including right prefrontal and parietal areas. The type of encoding strategy produced different brain activity patterns. There was no effect of encoding strategy on brain activity during recognition. The left inferior prefrontal cortex was engaged during encoding regardless of strategy.
Bernstein, L.J., Beig, S., Siegenthaler, A.L. & Grady, C.L. 2002. The effect of encoding strategy on the neural correlates of memory for faces. Neuropsychologia, 40 (1), 86 - 98.
http://tinyurl.com/i87v
May 2009
Meditation may increase gray matter
Adding to the increasing evidence for the cognitive benefits of meditation, a new imaging study of 22 experienced meditators and 22 controls has revealed that meditators showed significantly larger volumes of the right hippocampus and the right orbitofrontal cortex, and to a lesser extent the right thalamus and the left inferior temporal gyrus. There were no regions where controls had significantly more gray matter than meditators. These areas of the brain are all closely linked to emotion, and may explain meditators' improved ability in regulating their emotions.
Luders, E. et al. 2009. The underlying anatomical correlates of long-term meditation: Larger hippocampal and frontal volumes of gray matter. NeuroImage, 45 (3), 672-678.
http://www.eurekalert.org/pub_releases/2009-05/uoc--htb051209.php
February 2004
Special training may help people with autism recognize faces
People with autism tend to activate object-related brain regions when they are viewing unfamiliar faces, rather than a specific face-processing region. They also tend to focus on particular features, such as a mustache or a pair of glasses. However, a new study has found that when people with autism look at a picture of a very familiar face, such as their mother's, their brain activity is similar to that of control subjects – involving the fusiform gyrus, a region in the brain's temporal lobe that is associated with face processing, rather than the inferior temporal gyrus, an area associated with objects. Use of the fusiform gyrus in recognizing faces is a process that starts early with non-autistic people, but does take time to develop (usually complete by age 12). The study indicates that the fusiform gyrus in autistic people does have the potential to function normally, but may need special training to operate properly.
Aylward, E. 2004. Functional MRI studies of face processing in adolescents and adults with autism: Role of experience. Paper presented February 14 at the annual meeting of the American Association for the Advancement of Science in Seattle.
Dawson, G. & Webb, S. 2004. Event related potentials reveal early abnormalities in face processing autism. Paper presented February 14 at the annual meeting of the American Association for the Advancement of Science in Seattle.
http://www.eurekalert.org/pub_releases/2004-02/uow-stm020904.php
December 2004
How the brain recognizes a face
Face recognition involves at least three stages. An imaging study has now localized these stages to particular regions of the brain. It was found that the inferior occipital gyrus was particularly sensitive to slight physical changes in faces. The right fusiform gyrus (RFG), appeared to be involved in making a more general appraisal of the face and compares it to the brain's database of stored memories to see if it is someone familiar. The third activated region, the anterior temporal cortex (ATC), is believed to store facts about people and is thought to be an essential part of the identifying process.
Rotshtein, P., Henson, R.N.A., Treves, A., Driver, J. & Dolan, R.J. 2005. Morphing Marilyn into Maggie dissociates physical and identity face representations in the brain. Nature Neuroscience, 8, 107-113.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/4086319.stm
June 2005
How sleep improves memory
While previous research has been conflicting, it does now seem clear that sleep consolidates learning of motor skills in particular. A new imaging study involving 12 young adults taught a sequence of skilled finger movements has found a dramatic shift in activity pattern when doing the task in those who were allowed to sleep during the 12 hour period before testing. Increased activity was found in the right primary motor cortex, medial prefrontal lobe, hippocampus and left cerebellum — this is assumed to support faster and more accurate motor output. Decreased activity was found in the parietal cortices, the left insular cortex, temporal pole and fronto-polar region — these are assumed to reflect less anxiety and a reduced need for conscious spatial monitoring. It’s suggested that this is one reason why infants need so much sleep — motor skill learning is a high priority at this age. The findings may also have implications for stroke patients and others who have suffered brain injuries.
Walker, M.P., Stickgold, R., Alsop, D., Gaab, N. & Schlaug, G. 2005. Sleep-dependent motor memory plasticity in the human brain.Neuroscience, 133 (4) , 911-917.
http://www.eurekalert.org/pub_releases/2005-06/bidm-ssh062805.php
May 2005
Brain networks change according to cognitive task
Using a newly released method to analyze functional magnetic resonance imaging, researchers have demonstrated that the interconnections between different parts of the brain are dynamic and not static. Moreover, the brain region that performs the integration of information shifts depending on the task being performed. The study involved two language tasks, in which subjects were asked to read individual words and then make a spelling or rhyming judgment. Imaging showed that the lateral temporal cortex (LTC) was active for the rhyming task, while the intraparietal sulcus (IPS) was active for the spelling task. The inferior frontal gyrus (IFG) and the fusiform gyrus (FG) were engaged by both tasks. However, Dynamic Causal Modeling (the new method for analyzing imaging data) revealed that the network took different configurations depending on the goal of the task, with each task preferentially strengthening the influences converging on the task-specific regions (LTC for rhyming, IPS for spelling). This suggests that task specific regions serve as convergence zones that integrate information from other parts of the brain. Additionally, switching between tasks led to changes in the influence of the IFG on the task-specific regions, suggesting the IFG plays a pivotal role in making task-specific regions more or less sensitive. This is consistent with previous studies showing that the IFG is active in many different language tasks and plays a role in integrating brain regions.
Bitan, T., Booth, J.R., Choy, J., Burman, D.D., Gitelman, D.R. & Mesulam, M-M. 2005. Shifts of Effective Connectivity within a Language Network during Rhyming and Spelling. Journal of Neuroscience, 25, 5397-5403.
http://www.eurekalert.org/pub_releases/2005-06/nu-bnc060105.php
March 2009
Unraveling the roots of dyslexia
There is some evidence that dyslexia is distinguished by a basic deficit in phonological processing, characterized by difficulties in segmenting spoken words into their minimally discernable speech segments (speech sounds, or phonemes). A new study investigating brain activity of dyslexics and normal adult readers when presented with letters, speech sounds, or a matching or non-matching combination of the two, has revealed that dyslexic adults showed lower activation of the superior temporal cortex when needing to integrate letter and speech sounds. The findings point to reading failure being caused by a neural deficit in integrating letters with their speech sounds.
Blau, V. et al. 2009. Reduced Neural Integration of Letters and Speech Sounds Links Phonological and Reading Deficits in Adult Dyslexia. Current Biology, 19 (6), 503-508.
http://www.eurekalert.org/pub_releases/2009-03/cp-utr030509.php
April 2004
Brain region involved in insight localized
An imaging study has revealed a unique neural signature of those “Aha!” moments of sudden insight. Participants were given word problems which can be solved quickly with or without insight, and asked to press a button to indicate whether they had solved the problem using insight, which they had been told leads to an Aha! experience characterized by suddenness and obviousness. While several regions in the cerebral cortex showed about the same heightened activity for both insight and noninsight-derived solutions, only an area known as the anterior superior temporal gyrus in the right hemisphere showed a robust insight effect. The researchers also found that 0.3 seconds before the subjects indicated solutions achieved through insight, there was a burst of neural activity of one particular type: high-frequency (gamma band) activity that is often thought to reflect complex cognitive processing. This supports the view that the insight process involves integration of distantly related information.
Jung-Beeman, M., Bowden, E.M., Haberman, J., Frymiare, J.L., Arambel-Liu, S. et al. 2004. Neural activity when people solve verbal problems with insight. PLoS Biol 2(4): e97 DOI: 10.1371/journal.pbio.0020097
Full text available at http://www.plosbiology.org/plosonline/?request=get-document&doi=10.1371/journal.pbio.0020097
http://www.eurekalert.org/pub_releases/2004-04/plos-itb040604.php