Researchers ferret out function of autism gene

The structure of the protein NHE9 is one piece of the puzzle of what causes autism. 

Credit: Kalyan Kondapalli and Rajini Rao

Researchers say it's clear that some cases of autism are hereditary, but have struggled to draw direct links between the condition and particular genes.

Now a team at the Johns Hopkins University School of Medicine, Tel Aviv University and Technion-Israel Institute of Technology has devised a process for connecting a suspect gene to its function in autism.

In a report in the Sept. 25 issue of Nature Communications, the scientists say mutations in one such autism-linked gene, dubbed NHE9, which is involved in transporting substances in and out of structures within the cell, causes communication problems among brain cells that likely contribute to autism.

"Autism is considered one of the most inheritable neurological disorders, but it is also the most complex," says Rajini Rao, Ph.D., a professor of physiology in the Institute for Basic Biomedical Sciences at the Johns Hopkins University School of Medicine.

"There are hundreds of candidate genes to sort through, and a single genetic variant may have different effects even within the same family. This makes it difficult to separate the chaff from the grain, to distinguish harmless variations from disease-causing mutations. We were able to use a new process to screen variants in one candidate gene that has been linked to autism, and figure out how they might contribute to the disorder."

An estimated one in 88 children in the United States is affected by autism spectrum disorders, a group of neurological development conditions marked by varying degrees of social, communication and behavioral problems.

Scientists for years have looked for the biological roots of the problem using tools such as genome-wide association studies and gene-linkage analysis, which crunch genetic and health data from thousands of people in an effort to pinpoint disease-causing genetic variants.

But while such techniques have turned up a number of gene mutations that may be linked to autism, none of them appear in more than 1 percent of people with the condition. With numbers that low, researchers need a way to screen variants in order to make a definitive link, Rao says.

For the new study, Rao and her collaborators focused on NHE9, which other researchers had flagged as a suspect in attention-deficit hyperactivity disorder, addiction and epilepsy as well as autism spectrum disorders.

The gene was already known to be involved in transporting hydrogen, sodium and potassium ions in and out of cellular compartments called endosomes, and the team wondered how this function might be related to neurological conditions.

Rao's collaborators at Tel Aviv University and Technion-Israel Institute of Technology constructed a computer model of the NHE9 protein based on previous research on a distant relative in bacteria.

They then used the model to predict how autism-linked variants in the NHE9 gene would affect the protein's shape and function.

Some of them were predicted to cause dramatic changes, while other changes appeared to be more subtle.

Rao's team next tested how these variant forms of NHE9 would affect a relatively simple organism often used in genetic studies: yeast.

"Using yeast to screen the function of variants was a quick, easy and inexpensive way of figuring out which were worth further study, and which we could ignore because they didn't have any effect," Rao says.

To do that, the team engineered the yeast form of NHE9 to have the variants seen in autistic people.

For those mutations that did have a detectable effect on the yeast, the team moved on to a third and more challenging step, in mouse brains.

They homed in on astrocytes, a type of brain cell that clears the signaling molecule glutamate out of the way after it has performed its job of delivering a message across a synapse between two nerve cells.

Using lab-grown mouse astrocytes with variant forms of NHE9, the researchers found a change in the pH (acidity) inside cellular compartments called endosomes, which in turn altered the ability of cells to take up glutamate.

Because endosomes are the vehicles that deliver cargo essential for communication between brain cells, changing their pH alters traffic to and from the cell surface, which could affect learning and memory, Rao says.

"Elevated glutamate levels are known to trigger seizures, perhaps explaining why autistic patients with mutations in NHE9 and related genes also have seizures," she notes.

Rao and her team hope that pinpointing the importance of this trafficking mechanism in autism spectrum disorders may lead to the development of new drugs for autism that alter endosomal pH.

As the use of genomic data becomes increasingly commonplace in the future, the step-wise strategy devised by her team can be used to screen gene variants and identify at-risk patients, she says.

More information: www.nature.com/ncomms/2013/130925/ncomms3510/full/ncomms3510.html

Autistic Children: Sleep education helps families

Parent sleep education is beneficial in improving sleep and aspects of daytime behavior and family functioning in children with autism spectrum disorders (ASD), according to a Vanderbilt study published in the Journal of Autism and Developmental Disorders.

Vanderbilt joined with the University of Colorado Denver and the University of Toronto to carry out a study of 80 children with ASD, ages 2-10 years, primarily focused on teaching parents the basics of sleep education.

Beth Malow

"We found that one hour of one-on-one sleep education or four hours of group sleep education delivered to parents, combined with two brief follow-up phone calls, improved sleep as well as anxiety, attention, repetitive behaviour and quality of life in children with ASD who had difficulty falling asleep," said study author Beth Malow, M.D., professor of Neurology and Pediatrics, and the Burry Professor of Cognitive Childhood Development.

"The parents also benefited; they reported a higher level of parenting competence after completing the education sessions. The one-on-one and group sessions showed similar levels of success. In contrast, an earlier study that simply gave parents a pamphlet without guidance on how to use it did not provide the same level of improvement in child sleep."

Before entering the study, all children were examined for medical conditions that could cause sleep problems, such as gastrointestinal disorders or seizures.

In the instructional sessions, parents learned about daytime and evening habits that promote sleep, including the importance of increasing exercise, limiting caffeine during the day and minimizing use of video games and computers close to bedtime.

Sleep educators helped parents put together a visual schedule for their children to help them establish a bedtime routine and discussed ways to help children get back to sleep if they woke up at night.

Malow, also a Vanderbilt Kennedy Center investigator, said future studies are needed to determine the best approaches for providing sleep education to families, including those related to telemedicine and Internet-based technologies.

Malow and her colleagues within the Autism Speaks Autism Treatment Network are also developing partnerships with local pediatric practices to provide training on sleep education.

Content from the sessions is available to download for free on the Autism Speaks website. A toolkit, "Strategies to Improve Sleep in Children with Autism Spectrum Disorders," and three Quick Tips sheets are currently posted here.

"We are grateful to Autism Speaks for all of their support with our research and our toolkit materials. With their support, we have been able to help many children with ASD and their families get the rest they need to be at their best during the day," Malow said.

"We are also appreciative to all of the families who participated in this research."

TBI: Massive Increase in Emergency room visits for kids with concussions

Researchers report a skyrocketing increase in the number of visits to the emergency department for kids with sports-related traumatic brain injuries (TBI), such as concussions.

The study, conducted by emergency physicians at Cincinnati Children's Hospital Medical Center, shows that emergency visits for sports-related TBI increased 92 percent between 2002 and 2011.

The number of children and teens admitted to the hospital with the same diagnosis also increased. That increase was proportionate to the increase in emergency department visits – about 10 percent.

Patients admitted during the later years of the time period had less severe injuries and stayed in the hospital shorter amounts of time.

"More people are seeking care for TBI in the emergency department, and proportionately more are being admitted for observation," says Holly Hanson, MD, an emergency medicine fellow at Cincinnati Children's and lead author of the study.

"Here in Cincinnati, we anticipate more children will be seeing their primary care physician or going to the Cincinnati Children's TBI clinic, due to the passage of recent Ohio legislation mandating medical clearance to return to play."

The study of emergency department trends in sports-related TBI is published online in the journal Pediatrics.

The researchers studied more than 3,800 children and teens who came to Cincinnati Children's with a sports-related TBI between 2002 and 2011. Of these patients, 372 were admitted.

Injury severity, however, decreased from 7.8 to 4.8, based on an established medical score to measure trauma severity. Length of stay changed little but trended downward.

Skiing, sledding, inline skating and skateboarding had the highest admission rates for patients who visited the emergency department.

Their research did not concentrate on why more children and teens with less severe injuries were admitted to the hospital during this time period.

They speculate that emergency physicians may be ordering fewer CT scans and observing patients in the hospital, or perhaps that athletes are getting bigger and stronger, causing more head injuries needing longer periods of observation.

The Centers for Diseases Control and Prevention has called TBI an "invisible epidemic" because these injuries are often profound but not readily apparent to the public.

TBI is responsible for approximately 630,000 emergency visits, more than 67,000 hospitalizations, and 6,100 deaths in children and teens each year.

Medical evaluations for sports-related TBI increased 62 percent between 2001 and 2009, according to previous studies.

More Information: Sports related head injuries
Read more about minor head injuries on children

Leadership and Energy: Newborn Babies and Dogs: Stage 2: The Sitter and the Food Thief

At this stage, your baby is sitting without support, so you’ve likely begun feeding purees and may even be ready to start solid foods.

Pretty soon your dog will discover just how rewarding having this new family member around can be.

All babies enjoy throwing their food to see what happens, but your baby gets an added benefit:

The entertainment of watching your dog beg, jump, and dive for tasty morsels. In fact, your baby may enjoy offering food directly to your dog, making it even harder to discourage this kind of thievery.

So what can you do to keep baby’s mealtime under control?
Know your dog. Is he the type to sneak a treat from the kitchen table? Does she get possessive over particularly delectable snacks?

Recognizing the issues you may confront before the first feeding can help prepare you for that first meal.

Claim the high chair. Set clear rules, boundaries, and limitations from day one. Bring it out before you’re even considering feeding your baby anything besides breast milk and formula, and let your dog know who owns it. Then take things up a notch by adding some food to the tray.

Get help. It can be hard to keep track of an unruly dog and an unruly baby at the same time.

Even if you don’t expect to have any issues with your dog, plan for the first meal to be at a time when there’s someone else at home, so one of you can focus on correcting the dog and one of you can focus on the baby’s needs.

Beware of dangerous human foods. Most of the food that you will be feeding your baby at this stage will be mild on the stomach.

In fact, some veterinarians even recommend feeding baby food to a dog with a troubled tummy. But that doesn’t mean that all food you feed to your baby is safe for your dog.

For example, avocado is a great treat for a baby — but potentially dangerous for your pup and any sudden shift in diet can wreak havoc on a dog’s tummy.

Keep a list of foods to beware of near the fridge as a reminder, and talk to your veterinarian about any concerns you have.

Put the dog away. If you have any fears about your baby being hurt by an overexcited or possessive pup, make dinner a time when the dog goes away for a while but be aware that this issue won’t go away over time.

Eventually, your baby will grow into a toddler who will want to walk and snack. Consider hiring a professional to work through the issue.

Leadership and energy: 5 Stages of Baby, Canine Friendship - Part 1

You spent the last nine months preparing your dog for this new family member, and the introduction and initial meeting went well but that’s just the beginning!

Your dog’s relationship with your baby will change over time. At each stage of your baby’s development, you’ll encounter new joys and new challenges.

The key is to be alert to changes and to monitor interactions between them so you can step in and correct problem behaviour — from either your dog or your baby!

Here are a few of the dynamics you may encounter as your baby grows — and how to get through them as a pack.

Stage 1: Newborn and the Baby Alarm
A newborn brings a whole range of new smells and sounds into your home, and perhaps the most worrying is crying.

Remember, your dog picks up on energy, and the energy that your baby is giving off while crying is anything but calm and assertive. Your dog may become distressed, too, whimpering, whining, and barking.

This may be endearing at times (“Aww, look — Spot is worried about you, too!”), but it can also be a problem.

A barking dog can get in the way when you’re trying to get a baby to sleep, and often those crying jags happen in the middle of the night, when your neighbors may not appreciate the commotion.

You can help accustom your canine (and human!) family members to the sounds of crying before the new arrival by playing the sound on your computer at loud volumes for extended periods of time.

If possible, keep your dog some place where the noises of the baby can’t reach him at night. (That way, at least someone is the house is getting a good night’s sleep!)

NB: If you have issues with your newborn baby sleeping go to www.dream-angus.com for solutions and counselling.

One of the most important things you can do during this stage is maintain a regular routine of walks with the whole pack — mom and baby out the door first and at the front of the pack.

This not only helps send a message about your baby’s role as a pack leader, but also helps drain your dog’s energy, leading to better behavior overall.

With all the changes of having a new baby, many new parents put dog walks on the back burner, resorting to just letting the dog out in the backyard or a quick stop to the corner.

Of course, you may have days where this is simply a necessity, but make that the exception to the rule. Consider dog walks a priority. It’s not just good for your dog; it’s good for you, too.

Leadership and energy: Prepare your dog for the New Baby - Cesar Milan

Our dogs are very in tune with us, so with an event as monumental as a pregnancy, your dog has already sensed that something is up.

But just because she has picked up on the new feelings hanging in the air, doesn't mean that she understands what they mean.

Here are a few tips for preparing your dog for the new arrival.

Focus on leadership. 
Nine months is more than enough time for you and your pet to work through most issues and smooth out any unwanted habits, and for you to establish yourself as the unwavering pack leader.

If necessary, hire a professional to work with you. You will appreciate the work you put in now when you bring your newborn home to a calm, well-behaved dog.

Be aware of your energy.
A pregnancy affects the entire household. You may feel excited, anxious, or worried. Remember, your dog will mirror your emotions.

Claim your baby's scent.
Bring an item that contains your baby's scent, such as a burp cloth, from the hospital before bringing home the baby. During this exercise, it is crucial that you set clear boundaries.

Challenge the dog to sniff from a distance, while you are holding the item. By doing so, you are communicating to your dog that the item is yours and then giving permission for the dog to sniff.

"This new item belongs to me, and you will need to follow my rules when around it." This helps start the process of creating respect for the baby.

Establish boundaries around the nursery.
I recommend starting with the nursery off-limits. Condition your dog to understand that there is an invisible barrier that she may not cross without your permission.

Eventually, you can allow your dog to explore and sniff certain things in the room with your supervision. Then you decide when she needs to leave.

Repeat this activity a few times before the baby arrives. This will let your dog know that this room belongs to its pack leader and must be respected at all times.

Control the introduction.
Start by taking your dog on a long walk. Be sure to drain all of your dog's energy.

Before returning, wait at the door step; make sure your dog is in a calm-submissive state before inviting her in.

Upon entering, your dog will instantly know there is a new scent in the house. If you have already introduced the scent, it will be somewhat familiar.

The mother or father holding the baby must be in a completely calm state. The dog should be allowed to sniff the baby, but at a respectful distance.

During this first meeting, do not bring the baby too close. Eventually, the dog can be allowed to get closer and closer to the baby.

By doing this, you are teaching the dog to respect the baby as another pack leader.

Teach your baby.
Once your child is in the exploratory state, it is important to supervise all interactions between him or her and the dog.

This is a great opportunity to teach your child not to bother the dog, yank her tail, etc. These lessons on mutual respect cannot begin early enough.

Too many children have inadvertently provoked an otherwise peaceful dog, simply because they were unsupervised or their parents had not given them proper instruction.

Don't forget the dog.
A dog does not need toys or special attention to feel important; you simply need to maintain the routine, providing exercise and control, daily walks and consistent leadership.

This will help your dog feel secure and allow her to relax about the new addition to the family.

Forget breed. 
Don't assume your dog will (or will not) pose a problem based on breed alone. Sure, babies have been bitten by Rottweilers and pit bulls, but they have also been injured by labs, chows, and mixed breeds.

A baby in Rhode Island, NY was killed by a so-called cute little Pomeranian.

What is the key? 
Leadership. Be honest with yourself. Can you control your dog at all times in all situations?

Your child's safety comes first. If, after working with a professional and on your own, you are still not 100% confident about the safety of your baby with your dog, then finding your dog another home to protect the well-being of your child and pet is a step you may have to take.

Read more on Leadership, Dogs and babies at Cesar Milan website

Premature Babies: Sugar Gel protects against brain damage

A dose of sugar given as a gel rubbed into the inside of the cheek is a cheap and effective way to protect premature babies against brain damage, say experts.

Dangerously low blood sugar affects about one in 10 babies born too early. Untreated, it can cause permanent harm.

Researchers from New Zealand tested the gel therapy in 242 babies under their care and, based on the results, say it should now be a first-line treatment.

Their work is published in The Lancet.

Sugar dose 
Dextrose gel treatment costs just over £1 per baby and is simpler to administer than glucose via a drip, say Prof Jane Harding and her team at the University of Auckland.

Current treatment typically involves extra feeding and repeated blood tests to measure blood sugar levels.

But many babies are admitted to intensive care and given intravenous glucose because their blood sugar remains low - a condition doctors call hypoglycaemia.

The study assessed whether treatment with dextrose gel was more effective than feeding alone at reversing hypoglycaemia.

Neil Marlow, from the Institute for Women's Health at University College London, said that although dextrose gel had fallen into disuse, these findings suggested it should be resurrected as a treatment.

We now had high-quality evidence that it was of value, he said.

Andy Cole, chief executive of premature baby charity Bliss, said: "This is a very interesting piece of new research and we always welcome anything that has the potential to improve outcomes for babies born premature or sick.

PTSD: Identifying trauma risk in small children early after an accident

Small children also suffer from post-traumatic stress disorders (PTSD) after a serious accident. With the aid of a new test, children with an increased risk can already be identified in the space of a few days.

The test devised by scientists from the University of Zurich and the University Children's Hospital Zurich helps to treat traumatized small children at an early stage.

Accidents also traumatize small children. Around one in ten children still suffers from a post-traumatic stress disorder a year after a road accident or burn injury, reliving aspects of the traumatic experience in the form of flashbacks or nightmares.

In doing so, young children keep replaying the stressful memories while avoiding anything that might remind them of the accident in any way.

As a result of this constant alertness to threatening memories, the children can develop sleeping disorders, concentration problems or aggressive behaviour.

Assessing the risk of illness accurately
Researchers from the University of Zurich and the University Children's Hospital Zurich have now devised and evaluated a systematic questionnaire, which can be used to identify pre-school children with an increased risk of long-term post-traumatic disorders within a few days of an accident.

Markus Landolt

For the first time, it is now possible for first responders such as pediatricians, nursing staff or emergency psychologists to assess small children accurately with regard to their risk of illness.

"Children with an increased risk can thus be identified early and referred to an emergency psychologist for treatment," explains Professor Markus Landolt.

This prevents an acute stress response from developing into chronic mental illness that causes the child to suffer and spells a lengthy and expensive course of treatment.

For the study, Professor Landolt's doctoral student Didier Kramer interviewed a total of 134 parents of two to six-year-old children seven days after a road accident or burn injury.

Didier Kramer

The screening instrument used comprised 21 questions on changes in the child's behavior after the accident and recorded a high degree of accuracy: 85 percent of the children examined who suffered from a post-traumatic stress disorder after six months had already been identified correctly a week after the accident with the aid of the questionnaire.

Markus Landolt is now planning an app for Smartphones in collaboration with IT scientists: "This app will enable the screening to be conducted even more easily and quickly, and above all implemented broadly."

More information: Didier N. Kramer, Matthias B. Hertli, & Markus A. Landolt. Evaluation of an early risk screener for PTSD in preschool children after accidental injury. Pediatrics journal. September 23, 2013. DOI: 10.1542/peds.2013-0713

Autism: Some Children may be misdiagnosed - 22q11.2 deletion syndrome

Children with a genetic disorder called 22q11.2 deletion syndrome, who frequently are believed to also have autism, often may be misidentified because the social impairments associated with their developmental delay may mimic the features of autism, a study by researchers with the UC Davis MIND Institute suggests.

The study is the first to examine autism in children with chromosome 22q11.2 deletion syndrome, in whom the prevalence of autism has been reported at between 20 and 50 percent, using rigorous gold-standard diagnostic criteria.

The research found that none of the children with 22q11.2 deletion syndrome "met strict diagnostic criteria" for autism.

The researchers said the finding is important because treatments designed for children with autism, such as widely used discrete-trial training methods, may exacerbate the anxiety that is commonplace among the population.

Rather, evaluations should be performed to assess autism and guide the selection of appropriate therapies based on the children's symptoms, such as language and communication delay, the researchers said.

The study, "Social impairments in Chromosome 22q11.2 Deletion Syndrome (22q11.2DS): Autism Spectrum Disorder or a different Endophenotype?" is published online today in Springer's Journal of Autism and Developmental Disorders.

A high prevalence of autism spectrum disorder has been reported in children with 22q11.2 deletion syndrome – as high as 50 percent based on parent-report measures.

Children diagnosed with 22q11.2 deletion syndrome – or 22q – may experience mild to severe cardiac anomalies, weakened immune systems and malformations of the head and neck and the roof of the mouth, or palate.

They also experience developmental delay, with IQs in the borderline-to-low-average range. They characteristically experience significant anxiety and appear socially awkward.

Kathleen Angkustsiri

"The results of our study show that, of the children involved in our study, no child actually met strict diagnostic criteria for an autism spectrum disorder," said Kathleen Angkustsiri, study lead author and assistant professor of developmental-behavioural pediatrics at the MIND Institute.

"This is very important because the literature cites rates of anywhere from 20 to 50 percent of children with the disorder also have an autism spectrum disorder. Our findings lead us to question whether this is the correct label for these children who clearly have social impairments. We need to find out what interventions are most appropriate for their difficulties."

The disorder's name also describes its location on the 22nd chromosome as well as the nature of the genetic mutation, which is associated with a variety of anatomical and intellectual deficits.

It has previously been known as Velocardiofacial Syndrome and Di George Syndrome, for the pediatric endocrinologist who described it in the 1960s.

The risk of 22q is about 1 in 2000 in the general population. The condition is seen in individuals of all backgrounds. Notably, people with 22q are at significantly heightened risk of developing mental-health disorders in adolescence and young adulthood.

A person with 22q has a 30 times greater risk of developing schizophrenia than individuals in the general population.

Tony J. Simon

"Because of the high rates of psychiatric disorders in childhood and adulthood, 22q is a very special population for prospective study looking at what's happening throughout childhood that might either increase risk or provide protection against some of the later developing serious psychiatric illnesses, such as schizophrenia, that are associated with the disorder," said Tony J. Simon, professor of psychiatry and behavioral sciences and director of the chromosome 22q11.2 deletion program at the MIND Institute.

The study was conducted among individuals recruited through the website of the Cognitive Analysis and Brain Imaging Laboratory (CABIL), which Simon directs.

Simon and Angkustsiri said that the parents of children with 22q deletion syndrome often had commented that their children "seemed different" from other children with autism diagnoses, but that they hadn't discovered a better diagnosis.

The clinical impression of the MIND Institute's 22q deletion syndrome team, which includes psychologists Ingrid Leckliter and Janice Enriquez, was that the children were experiencing significant social impairments, but their presentation diverged from that of children with autism.

To determine whether the children met the criteria for classic autism, they decided to test a subset of the children recruited from participants in a larger study of neurocognitive functioning, based on stringent methods and using multiple testing instruments.

The researchers selected 29 children - 16 boys and 13 girls – for additional scrutiny, administering two tests.

• The Autism Diagnostic Observation Schedule (ADOS), a gold-standard assessment for autism, was administered to the children. 
• The Social Communication Questionnaire (SCQ), a 40-question parent screening tool for communication and 
• social functioning based on the gold-standard Autism Diagnostic Interview-Revised, was administered to their parents.

Typically, a diagnosis of autism spectrum disorder requires elevated scores on both a parent report measure, such as the SCQ, and a directly administered assessment such as the ADOS.

Prior studies of autism in chromosome 22q11.2 deletion syndrome have only used parent report measures.

Only five of the 29 children had scores in the elevated range on the ADOS diagnostic tool. Four of the five had significant anxiety.

Only two – 7 percent – had SCQ scores above the cut off. No child had both SCQ and ADOS scores in the relevant ranges that would lead to an ASD diagnosis.

"Over the years, a number of children came to us as part of the research or the clinical assessments that we perform, and their parents told us that they had an autism spectrum diagnosis. It's quite clear that children with the disorder do have social impairments," Simon said.

"But it did seem to us that they did not have a classic case of autism spectrum disorder. They often have very high levels of social motivation. They get a lot of pleasure from social interaction, and they're quite socially skilled."

Simon said that the team also noted that the children's social deficits might be more a function of their developmental delay and intellectual disability than autism.

"If you put them with their younger siblings' friends they function very well in a social setting," Simon continued, "and they interact well with an adult who accommodates their expectations for social interaction."

Angkustsiri said that further study is needed to assess more appropriate treatments for children with 22q, such as improving their communication skills, treating their anxiety, helping them to remain focused and on task.

"There are a variety of different avenues that might be pursued rather than treatments that are designed to treat children with autism," Angkustsiri said.

"There are readily available, evidence-based treatments that may be more appropriate to help maximize these children's potential."

Tip-of-the-Tongue Syndrome (TotTS) and Transactive Memory - An aside

Tip-of-the-tongue syndrome is an experience so common that cultures worldwide have a phrase for it.

Cheyenne Indians call it navonotootse’a, which means “I have lost it on my tongue”; in Korean it’s hyeu kkedu-te mam-dol-da, which has an even more gorgeous translation: “sparkling at the end of my tongue.”

The phenomenon generally lasts only a minute or so; your brain eventually makes the connection.

But … when faced with a tip-of-the-tongue moment, many of us have begun to rely instead on the Internet to locate information on the fly.

If life-logging … stores “episodic,” or personal, memories, Internet search engines do the same for a different sort of memory: “semantic” memory, or factual knowledge about the world.

When you visit Paris and have a wonderful time drinking champagne at a café, your personal experience is an episodic memory.

Your ability to remember that Paris is a city and that champagne is an alcoholic beverage – that’s semantic memory. …

What’s the line between our own, in-brain knowledge and the sea of information around us? Does it make us smarter when we can dip in so instantly? Or dumber with every search?

Thompson, the author of the book 'Smarter than you Think,' reminds us of the anecdote, by now itself familiar “to the point of banality,” about Socrates and his admonition that the “technology” of writing would devastate the Greek tradition of debate and dialectic, and would render people incapable of committing anything to memory because “knowledge stored was not really knowledge at all.”

He cites Socrates’s parable of the Egyptian god Theuth and how he invented writing, offering it as a gift to the king of Egypt, Thamus, who met the present with defiant indignation:

"This discovery of yours will create forgetfulness in the learners’ souls, because they will not use their memories; they will trust to the external written characters and not remember of themselves. 

 

The specific which you have discovered is an aid not to memory, but to reminiscence, and you give your disciples not truth, but only the semblance of truth; they will be hearers of many things and will have learned nothing; they will appear to be omniscient and will generally know nothing; they will be tiresome company, having the show of wisdom without the reality".

Read more of this article by Mary Popova