29 8 / 2013

27 2 / 2013

21 2 / 2013

neurosciencestuff:

Genome-wide imaging study identifies new gene associated with Alzheimer’s plaques
A study combining genetic data with brain imaging, designed to identify genes associated with the amyloid plaque deposits found in Alzheimer’s disease patients, has not only identified the APOE gene — long associated with development of Alzheimer’s — but has uncovered an association with a second gene, called BCHE.
A national research team, led by scientists at the Indiana University School of Medicine, reported the results of the study in an article in Molecular Psychiatry posted online Tuesday. The study is believed to be the first genome-wide association study of plaque deposits using a specialized PET scan tracer that binds to amyloid.
The research also is believed to be the first to implicate variations in the BCHE gene in plaque deposits visualized in living individuals who have been diagnosed with Alzheimer’s disease or are at-risk for developing the disease. The enzyme coded by the BCHE gene has previously been studied in post-mortem brain tissue and is known to be found in plaques.
“The findings could recharge research efforts studying the molecular pathways contributing to amyloid deposits in the brain as Alzheimer’s disease develops and affects learning and memory,” said Vijay K. Ramanan, the paper’s first author and an M.D./Ph.D. student at the IU School of Medicine.
The BCHE gene finding “brings together two of the major hypotheses about the development of Alzheimer’s disease,” said Andrew J. Saykin, Psy.D., Raymond C. Beeler Professor of Radiology and Imaging Sciences at IU and principal investigator for the genetics core of the Alzheimer’s Disease Neuroimaging Initiative.
Scientists have long pointed to the loss of an important brain neurotransmitter, acetylcholine, which is depleted early in the development of the disease, as a key aspect of the loss of memory related neurons. The BCHE gene is responsible for an enzyme that breaks down acetylcholine in the brain. The other major Alzheimer’s hypothesis holds that the development of the amyloid plaques is the primary cause of the disease’s debilitating symptoms. As it turns out, the enzyme for which the BCHE gene codes is also found in significant quantities in those plaques.
“This study is connecting two of the biggest Alzheimer’s dots,” said Dr. Saykin, director of the Indiana Alzheimer Disease Center and the IU Center for Neuroimaging at the IU Health Neuroscience Center.
“The finding that BCHE gene variant predicts the extent of plaque deposit in PET scans among people at risk for Alzheimer’s disease is likely to reinvigorate research into drugs that could modify the disease by affecting the BCHE enzyme or its metabolic pathway,” he said. Some existing drugs inhibit this enzyme, but it is unclear whether this influences plaque deposits.
Overall, the results appear to offer scientists new potential targets for drugs to slow, reverse or even prevent the disease. Alzheimer’s disease affects an estimated 5.4 million Americans and has proven resistant to treatments that do more than temporarily slow the worsening of symptoms.
Amyloid plaque deposits build up abnormally in the brains of Alzheimer’s patients and are believed to play an important role in the memory loss and other problems that plague patients.
The study makes use of an imaging agent, florbetapir, now approved for use by the U.S. Food and Drug Administration, that allows physicians to see the level of plaque buildup in a patient’s brain, something that previously could be determined only with an autopsy.
In a genome-wide association study, researchers evaluate alternate versions of many genes to determine whether particular genetic variants are associated with a particular trait — in this case, the amounts of amyloid plaque deposits that the PET scans revealed in the brains of study participants.
Using the imaging agent that enables detection of the plaques in the brain, the researchers conducted PET scans of 555 participants in the Alzheimer’s Disease Neuroimaging Initiative, a long-term public-private research project that includes people at risk for Alzheimer’s disease and patients who have been diagnosed with the disease as well as participants with no symptoms.
With sophisticated statistical analyses, the imaging data was combined with analyses of DNA collected from the 555 participants to determine whether particular gene variants were found more often among patients with higher levels of plaque deposits.
The analysis found that a variant in BCHE was significantly associated with the levels of plaque deposits. As would be expected, the analysis also found a strong association with variants of another gene, APOE, that has long been known to be associated with the development of Alzheimer’s. The effect of BCHE was independent of APOE, however. Moreover, the effects of the two genes were additive — that is, people with the suspect variants of both genes had more plaque deposits than people who had only one of the variants associated with plaque development.

neurosciencestuff:

Genome-wide imaging study identifies new gene associated with Alzheimer’s plaques

A study combining genetic data with brain imaging, designed to identify genes associated with the amyloid plaque deposits found in Alzheimer’s disease patients, has not only identified the APOE gene — long associated with development of Alzheimer’s — but has uncovered an association with a second gene, called BCHE.

A national research team, led by scientists at the Indiana University School of Medicine, reported the results of the study in an article in Molecular Psychiatry posted online Tuesday. The study is believed to be the first genome-wide association study of plaque deposits using a specialized PET scan tracer that binds to amyloid.

The research also is believed to be the first to implicate variations in the BCHE gene in plaque deposits visualized in living individuals who have been diagnosed with Alzheimer’s disease or are at-risk for developing the disease. The enzyme coded by the BCHE gene has previously been studied in post-mortem brain tissue and is known to be found in plaques.

“The findings could recharge research efforts studying the molecular pathways contributing to amyloid deposits in the brain as Alzheimer’s disease develops and affects learning and memory,” said Vijay K. Ramanan, the paper’s first author and an M.D./Ph.D. student at the IU School of Medicine.

The BCHE gene finding “brings together two of the major hypotheses about the development of Alzheimer’s disease,” said Andrew J. Saykin, Psy.D., Raymond C. Beeler Professor of Radiology and Imaging Sciences at IU and principal investigator for the genetics core of the Alzheimer’s Disease Neuroimaging Initiative.

Scientists have long pointed to the loss of an important brain neurotransmitter, acetylcholine, which is depleted early in the development of the disease, as a key aspect of the loss of memory related neurons. The BCHE gene is responsible for an enzyme that breaks down acetylcholine in the brain. The other major Alzheimer’s hypothesis holds that the development of the amyloid plaques is the primary cause of the disease’s debilitating symptoms. As it turns out, the enzyme for which the BCHE gene codes is also found in significant quantities in those plaques.

“This study is connecting two of the biggest Alzheimer’s dots,” said Dr. Saykin, director of the Indiana Alzheimer Disease Center and the IU Center for Neuroimaging at the IU Health Neuroscience Center.

“The finding that BCHE gene variant predicts the extent of plaque deposit in PET scans among people at risk for Alzheimer’s disease is likely to reinvigorate research into drugs that could modify the disease by affecting the BCHE enzyme or its metabolic pathway,” he said. Some existing drugs inhibit this enzyme, but it is unclear whether this influences plaque deposits.

Overall, the results appear to offer scientists new potential targets for drugs to slow, reverse or even prevent the disease. Alzheimer’s disease affects an estimated 5.4 million Americans and has proven resistant to treatments that do more than temporarily slow the worsening of symptoms.

Amyloid plaque deposits build up abnormally in the brains of Alzheimer’s patients and are believed to play an important role in the memory loss and other problems that plague patients.

The study makes use of an imaging agent, florbetapir, now approved for use by the U.S. Food and Drug Administration, that allows physicians to see the level of plaque buildup in a patient’s brain, something that previously could be determined only with an autopsy.

In a genome-wide association study, researchers evaluate alternate versions of many genes to determine whether particular genetic variants are associated with a particular trait — in this case, the amounts of amyloid plaque deposits that the PET scans revealed in the brains of study participants.

Using the imaging agent that enables detection of the plaques in the brain, the researchers conducted PET scans of 555 participants in the Alzheimer’s Disease Neuroimaging Initiative, a long-term public-private research project that includes people at risk for Alzheimer’s disease and patients who have been diagnosed with the disease as well as participants with no symptoms.

With sophisticated statistical analyses, the imaging data was combined with analyses of DNA collected from the 555 participants to determine whether particular gene variants were found more often among patients with higher levels of plaque deposits.

The analysis found that a variant in BCHE was significantly associated with the levels of plaque deposits. As would be expected, the analysis also found a strong association with variants of another gene, APOE, that has long been known to be associated with the development of Alzheimer’s. The effect of BCHE was independent of APOE, however. Moreover, the effects of the two genes were additive — that is, people with the suspect variants of both genes had more plaque deposits than people who had only one of the variants associated with plaque development.

21 2 / 2013

neurosciencestuff:

Learning and Memory May Play a Central Role in Synesthesia
People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme (i.e., the letter ‘A’ evokes the color red). In a new study, researchers Nathan Witthoft and Jonathan Winawer of Stanford University present data from 11 color grapheme synesthetes who had startlingly similar color-letter pairings that were traceable to childhood toys containing magnetic colored letters.
Their findings are published in Psychological Science, a journal of the Association for Psychological Science.
Matching data from the 11 participants showed reliably consistent letter-color matches, both within and between testing sessions (data collected online at http://www.synesthete.org/). Participants’ matches were consistent even after a delay of up to seven years since their first session.
Participants also performed a timed task, in which they were presented with colored letters for 1 second each and required to indicate whether the color was consistent with their synesthetic association. Their data show that they were able to perform the task rapidly and accurately.
Together, these data suggest that the participants’ color-letter associations are specific, automatic, and relatively constant over time, thereby meeting the criteria for true synesthesia.
The degree of similarity in the letter-color pairings across participants, along with the regular repeating pattern in the colors found in each individual’s letter-color pairings, indicates that the pairings were learned from the magnetic colored letters that the participants had been exposed to in childhood.
According to the researchers, these are the first and only data to show learned synesthesia of this kind in more than a single individual.
They point out that this does not mean that exposure to the colored letter magnets was sufficient to induce synesthesia in the participants, though it may have increased the chances. After all, many people who do not have synesthesia played with the same colored letter magnets as kids.
Based on their findings, Witthoft and Winawer conclude that a complete explanation of synesthesia must incorporate a central role for learning and memory.
(Image: Shutterstock)

neurosciencestuff:

Learning and Memory May Play a Central Role in Synesthesia

People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme (i.e., the letter ‘A’ evokes the color red). In a new study, researchers Nathan Witthoft and Jonathan Winawer of Stanford University present data from 11 color grapheme synesthetes who had startlingly similar color-letter pairings that were traceable to childhood toys containing magnetic colored letters.

Their findings are published in Psychological Science, a journal of the Association for Psychological Science.

Matching data from the 11 participants showed reliably consistent letter-color matches, both within and between testing sessions (data collected online at http://www.synesthete.org/). Participants’ matches were consistent even after a delay of up to seven years since their first session.

Participants also performed a timed task, in which they were presented with colored letters for 1 second each and required to indicate whether the color was consistent with their synesthetic association. Their data show that they were able to perform the task rapidly and accurately.

Together, these data suggest that the participants’ color-letter associations are specific, automatic, and relatively constant over time, thereby meeting the criteria for true synesthesia.

The degree of similarity in the letter-color pairings across participants, along with the regular repeating pattern in the colors found in each individual’s letter-color pairings, indicates that the pairings were learned from the magnetic colored letters that the participants had been exposed to in childhood.

According to the researchers, these are the first and only data to show learned synesthesia of this kind in more than a single individual.

They point out that this does not mean that exposure to the colored letter magnets was sufficient to induce synesthesia in the participants, though it may have increased the chances. After all, many people who do not have synesthesia played with the same colored letter magnets as kids.

Based on their findings, Witthoft and Winawer conclude that a complete explanation of synesthesia must incorporate a central role for learning and memory.

(Image: Shutterstock)

(via kosaddiq)

24 1 / 2013

neurosciencestuff:

Learning and Memory May Play a Central Role in Synesthesia
People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme (i.e., the letter ‘A’ evokes the color red). In a new study, researchers Nathan Witthoft and Jonathan Winawer of Stanford University present data from 11 color grapheme synesthetes who had startlingly similar color-letter pairings that were traceable to childhood toys containing magnetic colored letters.
Their findings are published in Psychological Science, a journal of the Association for Psychological Science.
Matching data from the 11 participants showed reliably consistent letter-color matches, both within and between testing sessions (data collected online at http://www.synesthete.org/). Participants’ matches were consistent even after a delay of up to seven years since their first session.
Participants also performed a timed task, in which they were presented with colored letters for 1 second each and required to indicate whether the color was consistent with their synesthetic association. Their data show that they were able to perform the task rapidly and accurately.
Together, these data suggest that the participants’ color-letter associations are specific, automatic, and relatively constant over time, thereby meeting the criteria for true synesthesia.
The degree of similarity in the letter-color pairings across participants, along with the regular repeating pattern in the colors found in each individual’s letter-color pairings, indicates that the pairings were learned from the magnetic colored letters that the participants had been exposed to in childhood.
According to the researchers, these are the first and only data to show learned synesthesia of this kind in more than a single individual.
They point out that this does not mean that exposure to the colored letter magnets was sufficient to induce synesthesia in the participants, though it may have increased the chances. After all, many people who do not have synesthesia played with the same colored letter magnets as kids.
Based on their findings, Witthoft and Winawer conclude that a complete explanation of synesthesia must incorporate a central role for learning and memory.
(Image: Shutterstock)

neurosciencestuff:

Learning and Memory May Play a Central Role in Synesthesia

People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme (i.e., the letter ‘A’ evokes the color red). In a new study, researchers Nathan Witthoft and Jonathan Winawer of Stanford University present data from 11 color grapheme synesthetes who had startlingly similar color-letter pairings that were traceable to childhood toys containing magnetic colored letters.

Their findings are published in Psychological Science, a journal of the Association for Psychological Science.

Matching data from the 11 participants showed reliably consistent letter-color matches, both within and between testing sessions (data collected online at http://www.synesthete.org/). Participants’ matches were consistent even after a delay of up to seven years since their first session.

Participants also performed a timed task, in which they were presented with colored letters for 1 second each and required to indicate whether the color was consistent with their synesthetic association. Their data show that they were able to perform the task rapidly and accurately.

Together, these data suggest that the participants’ color-letter associations are specific, automatic, and relatively constant over time, thereby meeting the criteria for true synesthesia.

The degree of similarity in the letter-color pairings across participants, along with the regular repeating pattern in the colors found in each individual’s letter-color pairings, indicates that the pairings were learned from the magnetic colored letters that the participants had been exposed to in childhood.

According to the researchers, these are the first and only data to show learned synesthesia of this kind in more than a single individual.

They point out that this does not mean that exposure to the colored letter magnets was sufficient to induce synesthesia in the participants, though it may have increased the chances. After all, many people who do not have synesthesia played with the same colored letter magnets as kids.

Based on their findings, Witthoft and Winawer conclude that a complete explanation of synesthesia must incorporate a central role for learning and memory.

(Image: Shutterstock)

22 1 / 2013

22 1 / 2013

imagininglearning:

thankyoueducators:


Imagination will take you anywhere!



Imagining Learning believes that imagination and vision are necessary to truly transform education. We believe young people’s ability to access and use their imagination is key to unlocking deep wisdom about how schools can look in the present and the future! We believe that the visions and imagination of young people can take us anywhere! 


-Imagining Learning

imagininglearning:

thankyoueducators:

Imagination will take you anywhere!

Imagining Learning believes that imagination and vision are necessary to truly transform education. We believe young people’s ability to access and use their imagination is key to unlocking deep wisdom about how schools can look in the present and the future! We believe that the visions and imagination of young people can take us anywhere! 

(via adventuresinlearning)

22 1 / 2013

lookingforether:

“Our brains are a vastly parallel and distributed system, each with a gazillion decision-making points and centers of integration. The 24/7 brain never stops managing our thoughts, desires, and bodies. The millions of networks are a sea of forces, not single soldiers waiting for the commander to speak. It is also a determined system, not a freewheeling cowboy acting outside the physical, chemical forces that fill up our universe. And yet, these modern-day facts do not in the least convince us there is not a central “you,” a “self” calling the shots in each of us. Again, that is the puzzle, and our task is to try and understand how it all might work.” - Michael S.Gazzaniga 

lookingforether:

“Our brains are a vastly parallel and distributed system, each with a gazillion decision-making points and centers of integration. The 24/7 brain never stops managing our thoughts, desires, and bodies. The millions of networks are a sea of forces, not single soldiers waiting for the commander to speak. It is also a determined system, not a freewheeling cowboy acting outside the physical, chemical forces that fill up our universe. And yet, these modern-day facts do not in the least convince us there is not a central “you,” a “self” calling the shots in each of us. Again, that is the puzzle, and our task is to try and understand how it all might work.” - Michael S.Gazzaniga 

(via wildcat2030)

20 1 / 2013

imagininglearning:


This is what we are trying to do at Imagining Learning

imagininglearning:

This is what we are trying to do at Imagining Learning

(via adventuresinlearning)

19 1 / 2013

neurosciencestuff:

How the brain copes with multi-tasking alters with age
The pattern of blood flow in the prefrontal cortex in the brains alters with age during multi-tasking, finds a new study in BioMed Central’s open access journal BMC Neuroscience. Increased blood volume, measured using oxygenated haemoglobin (Oxy-Hb) increased at the start of multitasking in all age groups. But to perform the same tasks, healthy older people had a higher and more sustained increase in Oxy-Hb than younger people.
Age related changes to the brain occur earliest in the prefrontal cortex, the area of the brain associated with memory, emotion, and higher decision making functions. It is changes to this area of the brain that are also associated with dementia, depression and other neuropsychiatric disorders. Some studies have shown that regular physical activity and cognitive training can prevent cognitive decline (use it or lose it!) but to establish what occurs in a healthy aging brain researchers from Japan and USA have compared brain activity during single and dual tasks for young (aged 21 to 25) and older (over 65) people.
Near infrared spectroscopy (NIRS) measurements of Oxy-Hb showed that blood flow to the prefrontal cortex was not affected by the physical task for either age group but was affected by the mental task. For both the young and the over 65s the start of the calculation task  coincided with an increase in blood volume which reduced to baseline once the task was completed.
The main difference between the groups was only seen when performing the physical and mental tasks at the same time - older people had a higher prefrontal cortex response which lasted longer than the younger group.
Hironori Ohsugi, from Seirei Christopher University, and one of the team who performed this research explained “From our observations during the dual task it seems that the older people turn their attention to the calculation at the expense of the physical task, while younger people are able to maintain concentration on both. Since our subjects were all healthy it seems that this requirement for increased activation of the prefrontal cortex is part of normal decrease in brain function associated with aging. Further study will show whether or not dual task training can be used to maintain a more youthful brain.”
(Image: Photos.com)

neurosciencestuff:

How the brain copes with multi-tasking alters with age

The pattern of blood flow in the prefrontal cortex in the brains alters with age during multi-tasking, finds a new study in BioMed Central’s open access journal BMC Neuroscience. Increased blood volume, measured using oxygenated haemoglobin (Oxy-Hb) increased at the start of multitasking in all age groups. But to perform the same tasks, healthy older people had a higher and more sustained increase in Oxy-Hb than younger people.

Age related changes to the brain occur earliest in the prefrontal cortex, the area of the brain associated with memory, emotion, and higher decision making functions. It is changes to this area of the brain that are also associated with dementia, depression and other neuropsychiatric disorders. Some studies have shown that regular physical activity and cognitive training can prevent cognitive decline (use it or lose it!) but to establish what occurs in a healthy aging brain researchers from Japan and USA have compared brain activity during single and dual tasks for young (aged 21 to 25) and older (over 65) people.

Near infrared spectroscopy (NIRS) measurements of Oxy-Hb showed that blood flow to the prefrontal cortex was not affected by the physical task for either age group but was affected by the mental task. For both the young and the over 65s the start of the calculation task  coincided with an increase in blood volume which reduced to baseline once the task was completed.

The main difference between the groups was only seen when performing the physical and mental tasks at the same time - older people had a higher prefrontal cortex response which lasted longer than the younger group.

Hironori Ohsugi, from Seirei Christopher University, and one of the team who performed this research explained “From our observations during the dual task it seems that the older people turn their attention to the calculation at the expense of the physical task, while younger people are able to maintain concentration on both. Since our subjects were all healthy it seems that this requirement for increased activation of the prefrontal cortex is part of normal decrease in brain function associated with aging. Further study will show whether or not dual task training can be used to maintain a more youthful brain.”

(Image: Photos.com)