News reports of research into memory October 2007
For index of all headlines, go to News & Views main page
To look at research reports sorted by subject go to Research Reports
For news about Alzheimer's research go directly to the Alzheimer's page
You can find links to the journals referred to on this site here: Journal links
October 2007
10 minutes of talking has a mental payoff
A study of 3,610 people aged 24—96
examined mental functioning and social interaction, and found that, across all
ages, cognitive functioning was better the higher the level of participants'
social interaction. Participants' level of social interactions was assessed by
asking how often each week they talked on the phone with friends, neighbors and
relatives, and how often they got together. Researchers controlled for age,
education, race/ethnicity, gender, marital status and income, physical health
and depression. In a second experiment involving college students, short-term
social interaction lasting for just 10 minutes boosted participants'
intellectual performance as much as engaging in so-called 'intellectual'
activities for the same amount of time.
The study will be published in the
February 2008 issue of the Personality and Social Psychology Bulletin.
http://www.eurekalert.org/pub_releases/2007-10/uom-tmo102907.php
Depression increases risk of executive dysfunction in older people
A two-year study of more than 700
older adults (65 and older) has found that depression increased the risk of
declining executive function (high-level mental processes, such a making
decisions, organizing, planning and doing a series of things in sequence).
The study was published in the
August issue of The American Journal of Psychiatry.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uorm-dcf100807.php
Cognitive deficits among cancer patients insufficiently recognized problem
A survey of 471 cancer patients has
found that the cognitive impairment experienced by 14 to 45% of cancer patients
can be long-lasting and severely affect their personal and professional lives.
Patients report that the lack of concentration, short-term memory loss,
difficulty with word recall and the inability to organize or multi-task have led
to significant problems at home and in the workplace. 42% described their
doctors as dismissive or indifferent when it came to addressing their concerns.
To view the executive summary, visit
www.hurricanevoices.org/today/cognition.
http://www.eurekalert.org/pub_releases/2007-10/hvbc-cdl100107.php
Epilepsy-induced brain cell damage prevented
Epileptic seizures can result in
cognitive impairment. The cause of this was not clear, though some evidence
suggested that dendritic spines had been lost. Now new research with mice has
confirmed that, indeed, induced seizures caused
dendrites to swell and spines to
disappear. When the swelling went down, after the seizure, the spines did not
return. Further research revealed that this reaction was caused by the breakdown
of actin, a molecule widely used in cell structures. When the mice were given a
drug, FK506, prior to inducing seizures, they were able to block that breakdown.
The report appeared in the October
issue of The Journal of Neuroscience.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/wuso-ebc102907.php
Successful treatment for chronic TBI in rat study
A rat study has found that
hyperbaric oxygen therapy (HBOT) improved spatial learning and memory in a model
of chronic traumatic brain injury.
The paper is reported in the October 12 issue of Brain Research.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/lsuh-1st101107.php
Imaging shows structural changes in mild traumatic brain injury
A study involving patients with all
severities of traumatic brain injury has found that abnormalities in
white
matter existed across the spectrum, and that diffusion tensor imaging could
identify structural changes even in patients with mild traumatic brain injury,
who had minimal or no loss of consciousness, and even in those with no
self-reported cognitive deficit. The imaging could also distinguish between
axonal damage (tearing of the axons that allow one neuron to communicate with
another) in white matter versus abnormalities in the
myelin.
The study is published in the October issue of Brain.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uoia-iss102507.php
Stem cells improved memory in mice after brain injury
Brain damage in mice that
significantly impaired memory was repaired through the introduction of neural
stem cells. Interestingly, the stem cells did not primarily replace the dead
neurons, but somehow supported the injured neurons by, it is thought, making
beneficial proteins called
neurotrophins. If so, it may be that a similar
effect can be achieved by creating a drug that increases the release of
neurotrophins.
The results of the study appear in the October 31 issue of the Journal of Neuroscience.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uoc--scc102507.php
Mouse study points to new therapy for Fragile X sufferers
A mouse study has found evidence
that fragile X mutation produces a highly selective impairment to
long-term potentiation in hippocampal cells, and that adding
brain-derived neurotrophic factor (BNDF) proteins to the
hippocampus restored it.
The findings appeared in the October 3 issue of the Journal of Neuroscience.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uoc--urr100507.php
Effectiveness of most PTSD therapies is uncertain
A review of 53 studies of
pharmaceuticals and 37 studies of psychotherapies used in PTSD treatment has
concluded that because of shortcomings in many of the studies, there is not
enough reliable evidence to draw conclusions about the effectiveness of most
treatments. However, sufficient evidence exists to conclude that exposure
therapies — such as exposing individuals to a real or surrogate threat in a safe
environment to help them overcome their fears — are effective.
http://www.eurekalert.org/pub_releases/2007-10/tna-eom101807.php
Why emotion enhances memory
We know that emotion can increase
the memorability of events, but we haven’t known exactly why it does so. Now a
new study reveals that during emotional arousal, the stress hormone
norepinephrine makes
synapses dramatically more sensitive by increasing the
number of GluR1 receptors.
The report appeared in the October 5 issue of Cell.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/jhmi-wem100407.php
http://www.eurekalert.org/pub_releases/2007-10/cp-hec100107.php
http://www.brainatlas.org/aba/2007/071018/full/aba1787.shtml
Brain waves distinguish false memories from true
An imaging study of 52 neurosurgical
patients being treated for drug-resistant epilepsy has found that a fast brain
wave, known as the gamma rhythm, increased when participants studied a word that
they would later successfully recall. The same gamma waves also increased in the
half-second prior to participant’s correctly recalling an item. In other words,
the gamma waves predicted whether or not an item that was about to be recalled
was previously studied.
The study appeared in the November issue of Psychological Science.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uop-prp102307.php
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.
The report appeared in the November issue of the Journal of Neuroscience.
Full reference
http://www.physorg.com/news113671556.html
Genes implicated in learning attitude
It’s known that people are motivated
differently by positive and negative outcomes. Now a new study suggests that
whether you are a “positive” or “negative” learner is partly determined by your
genes. Three separate genes, all associated with the
neurotransmitter
dopamine,
were implicated. Two of the genes - DARPP-32 and DRD2 - predicted learning about
the average, long-term probability of rewards and punishments. These genes
control dopamine function in the striatum. The third gene,
COMT, predicted a
person's tendencies to change choice strategies after a single instance of
negative feedback. This gene affects dopamine function in the prefrontal cortex.
The results were reported in the
October 1 issue of the Proceedings of the National Academy of Sciences.
Full reference
http://www.eurekalert.org/pub_releases/2007-10/uoa-gmh092707.php
Adult neurogenesis confirmed in primates
A study with marmosets has confirmed
that the rate at which new neural cells form in the
hippocampus (neurogenesis)
begins to decline soon after reaching adulthood. This is the first study to
confirm the finding from rodent studies in primates, and confirms that findings
from rodent studies regarding ways of enhancing adult neurogenesis can be
applied to primates.
The study appeared in the October 23
issue of the Proceedings of the National Academy of Science.
Full reference
http://www.physorg.com/news111690164.html
http://www.eurekalert.org/pub_releases/2007-10/pu-bcg101207.php
Now available as a downloadable ebook!
