depiction of human brain

Memories: How Do They Form and Fade?

Have you ever wondered why some of your childhood memories are still fresh in your mind even after decades while some recent ones fade in minutes. Researchers have recently discovered the neural processes that cause some memories to fade quickly while making other memories stable over time.

Using mouse models, researchers from California Institute of Technology have determined that strong, stable memories are encoded by “teams” of neurons all working in synchrony, providing redundancy that enables these memories to stay over time. The study helps in understanding how brain damage due to strokes or Alzheimer’s disease may affect memory.

Published in the journal, Science, the study was conducted at Biology research professor, Carlos Lois’s laboratory. The professor is also an affiliated faculty member of the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech.

The team, led by Walter Gonzalez, a postdoctoral scholar developed a test to examine mice’s neural activity as they learn about and remember a new place. In the test, mice explored a 5-feet-long enclosure where unique symbols denoted different locations along its white walls. A treat (sugar water) for mice was place at both ends of the track. The activity of specific neurons in the mouse hippocampus (the region of the brain where new memories are formed) known to encode for places, was measured while the mouse walked around.

The researcher noted that when a mouse was first put in the track, it was not certain about what to do and so moved left and right until it came across the treat. In these cases, when a mouse took notice of a wall symbol, single neurons were activated. But over several experiences with the track, the mouse became familiar with it and remembered the site of the treat. As it became more familiar, more and more neurons were synchronously activated by seeing each symbol on the wall. Basically, the mouse was recognizing its own location with respect to each unique symbol.

In order to investigate how memories fade over time, the researchers then withheld mice from the enclosure for up to 20 days. Upon coming back to the track after the sabbatical, mice that had formed strong memories encoded by higher numbers of neurons remembered the task promptly. The mouse’s memory of the track was clearly identifiable when analyzing the activity of large groups of neurons, in spite of some neurons showing different activity. Alternatively, using groups of neurons enables the brain to recall memories while having redundancy, even if some of the original neurons fall silent or are damaged.

Gonzalez clarifies, “Imagine you have a long and complicated story to tell. In order to preserve the story, you could tell it to five of your friends and then occasionally get together with all of them to re-tell the story and help each other fill in any gaps that an individual had forgotten. Additionally, each time you re-tell the story, you could bring new friends to learn and therefore help preserve it and strengthen the memory. In an analogous way, your own neurons help each other out to encode memories that will persist over time.”

While earlier theories about memory storage suggest that making a memory more stable requires the strengthening of the connections to an individual neuron, this study proposes that increasing the number of neurons encoding the same memory enables the memory to stay for longer. The study has great implications for designing future treatment that could boost the recruitment of a higher number of neurons to encode a memory, and could help prevent memory loss.

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man working on laptop in dark

Study Indicates Why Worry Influences Concentration on Everyday Tasks

A recent research has demonstrated that worry affects regions of the brain that are crucial  for concentration. The study was conducted by researchers from the Department of Psychology in the University of Roehampton, London. Professor Paul Allen and his colleagues from the Department have examined how worry influences ‘attentional control’ or the brain areas that are involved in concentration.

The study involved the assessment of the participants for determining how often and how intensely they face worrying thoughts. They participants were made to undergo a functional Magnetic Resonance Imaging (fMRI) scan while carrying out a task requiring different levels of attentional control. The scan results indicated that, whilst all participants were able to effectively complete the task, higher levels of worry were associated with greater activity and reduced connectivity in the attentional control regions of the brain. This was evident particularly in the frontal cortex. This shows that worry impair attentional control particularly when task demands are high.

Professor Allen said “Everyone worries about things from time to time—some people more than others. Psychologists have known for some time that worry can affect our concentration, especially when we need to focus on difficult tasks. This finding suggests that worry can lead to less efficient use of neural resources and may explain why worry affects our ability to concentrate on everyday tasks.”

The study has significant implications for the understanding of how the brain and its ability to function normally are affected by emotions like worry and anxiety.

Also read:
Five Ways to Boost Your Concentration

Adele smiling

Celebrity Fat Shaming Adversely Affects All Women, Study

Celebrities, particularly female celebrities, are customarily criticized about their appearance in magazines and newspapers. While we generally don’t give much importance to those nasty headlines assuming they are trivial, little do we realize that the effects of such comments can extend well beyond the targeted person and ripple through the population at large.

A recent research published in Personality and Social Psychology Bulletin, a journal of the Society for Personality and Social Psychology, has shown that fat shaming celebrities may negatively impact all women’s body image or their attitude about their body.

Psychologists from McGill University in Montreal, Quebec, Canada used data collected from more than 93,000 women, predominantly from North America, between 2004 to 2015 and compared 20 instances of celebrity fat shaming with women’s implicit attitudes about weight two weeks before and two weeks after each celebrity fat-shaming event. The investigators found that there was an association between instances of celebrity fat shaming and an increase in women’s implicit negative weight-related attitudes. The fat-shaming events led to a spike in women’s implicit anti-fat attitudes, with more “notorious” events producing greater spikes. Besides, the researchers also found that implicit weight-bias was on the rise more generally.

“Fat shaming is socially acceptable and it’s so common we don’t know how pervasive it is. No one even bats an eyelash at it or thinks about how terrible it is for that person. But the consequences affect more than just the target of fat shaming,” said Amanda Ravary, a Ph.D. student at McGill University and the lead author of the study.

Jennifer Bartz, the study’s senior author and an associate professor of psychology at McGill University explained, “When you look at a headline and think, ‘This is terrible,’ that is your explicit attitude. Implicit attitude is whether you think something is good or bad.”

Explicit attitudes are those, which people consciously endorse and which are often susceptible to concerns about social desirability and presenting oneself in the most positive light. By contrast, implicit attitudes, around which this investigation also revolved, indicate people’s split-second gut-level reactions that something is inherently good or bad. Implicit attitudes are generally believed to be developed over a lifetime. “We constantly receive messages that things are good or bad, and the more we hear them, the stronger the association is,” Bartz explained. “These cultural messages appeared to augment women’s gut-level feeling that ‘thin’ is good and ‘fat’ is bad. These media messages can leave a private trace in people’s minds,” she added.

The next step in this research will be to include lab research, which would enable the researchers to manipulate exposure to fat-shaming messages (vs. neutral messages) and gauge the effect of these messages on women’s implicit anti-fat attitudes. The lab research is likely to provide more direct proof of the causal role of these cultural cues in women’s implicit attitudes.

Also read
Choose Wisely: People Around You Affect Your Body Image
8 Ways to Build a Positive and Healthy Body Image

mother taking away tablet from the child

Is Digital-Addiction a Real Menace to Children?

More and more children these days are battling digital addiction. They are being exposed to electronic devices at much younger ages, and we often watch them spending hours gazing at cell-phone/tablet or computer screens. According to experts, digital addiction is as potent as meth and can have alarming effects on children. It is extremely important to apply moderation, when it comes to screens or screen-time and we as parents must teach our children how to use them in a healthy way.

According to Dr Dimitri A. Christakis, Director, Center for Child Health, Behavior and Development, Seattle Children’s Research Institute and professor of pediatrics at the University of Washington, children use the devices along a continuum which ranges from healthy to compulsive to addictive. “I think the phenomenon of tech addiction is quite real,” he said.

In the commentary published in JAMA, Dr Christakis suggested that the relationship between media exposure and health in adolescents might turn out to follow an “inverted U” pattern. Thus, very high exposure and very low exposure might both be associated with poorer mental health outcomes than moderate amounts of usage.

However, though technology-use is as powerful as drugs, it is not analogous to drug use at all because these devices serve important purposes in our lives, including children’s. We as well as children need technology to do the day-to-day chores and stay connected but it is pertinent, given its adverse effects, to find healthy ways to use it adequately before its takes over.

Dr Ellen Selkie, an assistant professor of adolescent medicine at the University of Michigan, who does research on adolescents’ use of social media, said, “It’s like food, it’s something we all need because of the way businesses run, because of the job market—and for teens it’s the way they socialize.”

According to Dr Selkie, there is evidence that supports limitations on the absolute amount of screen time with younger children but the situation is more complicated, with older children. This is because, it is not that simple to make out whether a teen who is always on the phone, is there due to addiction or because that is where his friends are. It is normal for a teen to always want to be talking to his or her friends rather than the family.

However, just like other aspects of life that contribute to our overall well-being, it requires daily decisions on the user’s part to keep his or her technology-usage within healthy limits. Saying that one should altogether bring it down to zero is neither sensible nor acceptable given the benefits technology provides; however, we can certainly curb before we become its slaves instead of masters.

Dr Jenny Radesky, an assistant professor of developmental behavioral pediatrics at the University of Michigan and an expert on technology use by children, equates technology to “an environment.” It is a place where all sorts of activities take place, from work to entertainment to social life. However, she cautions that it is a deliberately designed and engineered environment, with an ultimate goal of making money. “Modern technologies is purposefully habit-forming and programmed with the sort of variable rewards that keep humans engaged.” she adds. It is important to not fall prey to it because it can potentially impact our healthiness in a negative way.

Dr Radesky also emphasizes that rather than the concerned individual, or the so-called addict, the problem lies with the digital environment which is shaping the individual’s behavior, often through methods that are intentionally exploitative or subconscious.

Therefore, it is essential for children to understand the way technology works for or against them. Parents can play a significant role in imparting and demystifying information and making their children more digitally literate.

While researchers often talk about the difficulty they experience in trying to understand and quantify children’s use of devices, Dr Christakis in his commentary, points out how while the required information is routinely—and efficiently—gathered by the industry and applied to increase the charm of the devices and the programs, people in academia and research are struggling to get the data needed to put together coherent and extensive guidelines for parents and policymakers. Dr Christakis, thus, suggests that an increased cooperation between industry and researchers might help in setting up those guidelines.

According to Dr Selkie, there are ways for tech companies and even game designers to be more thoughtful about children and to discourage problematic internet use.

In the meanwhile, parents should do their part and start with asking their children to put down their cell-phones while dinner or on family outings and gradually proceed to setting limits on per day screen-time. Parents themselves should also be mindful of their own use of devices and set good examples for their children.

Also read:
8 Ways to Prevent and Address Your Child’s Addiction to Smart Devices
The 4 Personal Traits That Make It Hard to Take Criticism
Study Explains Why People Lie
Why Children Lie and What Parents Can Do to Prevent It

a man taking a peldge while lying

Study Explains Why People Lie

We all were probably taught to never lie but there would be rarely anyone who can truthfully claim that he or she doesn’t lie or hasn’t lied in life, ever. Depending upon the demands of the situation, we might tell a lie for harmless reasons like to avoid awkward situations, protect others, or avoid hurting others’ feelings, or, for some other reasons that are much serious and can potentially wreak havoc on our lives. However, there are some people who lie out of habit. And, the more they lie, the easier and more frequent this behaviour becomes. Scientists have now discovered why liars lie.

Psychologists believe that children start lying at the age of two. Since lying involves paying attention to the environment, complex planning, and the ability to manipulate a situation, it is actually considered a crucial milestone in children’s development. While growing up, they keep on learning how to use this skill for their own benefit, and by the time they reach adulthood, their lies become much more clever, harder to catch, and easier to get away with.

Cognitive neuroscientist Joshua Greene from Harvard University investigated the physical process of lying during an experiment. Participants were given the opportunity to win money by lying. While some of them still stuck to being honest and told the truth, others resorted to deception. The MRI of the participants was performed to examine their brain activity during the study. The MRI reports revealed that there was an increased activity in the frontal parietal control network of the group of liars because deciding between honesty and lying requires hard and intricate thinking. Since the neural reward centers of the participants who won money by telling lies were more active, it can be assumed that lying may be a result of the inability to resist temptation.

However, there is still no scientific explanation as to why people tend to avoid lying and whether it is a result of conflict in their brains or an understanding of morality and self-control, or simply following the social norm. According to Dan Ariely, a behavioral psychologist at Duke, “We are our own judge about our own honesty. And that internal judge is what differentiates psychopaths and non-psychopaths.”

Apparently, despite that the urge to lie comes from within, external factors can influence the frequency too. Research has shown that people tend to be dishonest when they are suffering from stress or lack of sleep, or when they see others lying. “We as a society need to understand that when we don’t punish lying, we increase the probability it will happen again,” Ariely added.

Ariely and his colleagues conducted a study to show the change in participants’ brain while they are being dishonest. The study revealed that there was an increased activity in their amygdala, a part of the brain responsible for producing fear, anxiety and emotions. This change made lying or being dishonest easier for those participants. The signals from the amygdala reduced when they expected no consequences for being dishonest, such as when playing a game. Cognitive neuroscientist at University College London, Tali Sharot, who led the research said, “If you give people multiple opportunities to lie for their own benefit, they start with little lies and get bigger and bigger over time.”