Categories
Health and Disease

ADHD, ASD, and Schizophrenia

By Neha Menon

Published 1:00 AM EST, Sun May 30, 2021

Introduction – Psychological Disorders

Psychological disorders or mental illnesses are explained by the DSM-5: “…as a syndrome characterized by​ a clinically significant disturbance in an individual’s cognitive, emotion regulation, or behaviour that reflects a dysfunction in the psychological, biological, or developmental process underlying mental functioning.”[1]

This definition by the American Psychiatric Association’s diagnostic manual, broadly classifies certain disorders or abnormalities under a vast topic: psychological disorders. There are several psychological disorders and if we begin to study them one by one, we will observe distinct characteristics in each one. The scope of this article is to discuss 3 common psychological disorders: ASD, ADHD, and schizophrenia.

ASD: Autism Spectrum Disorder

ASD is most commonly diagnosed by the age of 2-3 with obvious symptoms. It is a complex developmental condition that challenges verbal & non-verbal communication, social interactions and repetitive or restricted behaviours. Autism is regarded as a “spectrum” disorder because of the range and severity of symptoms that can differ across patients. Some people with this disorder may also have intellectual delays. What’s more interesting about people with ASD is that the person’s cognitive functioning may either be delayed/challenged or very gifted. Some signs or symptoms amongst others that may indicate the existence of the disorder are as follows[2][3]:

  • have trouble relating to others or not have an interest in other people at all
  • avoid eye contact and want to be alone
  • have trouble understanding other people’s feelings or talking about their feelings
  • prefer not to be held or cuddled, or might cuddle only when they want to
  • appear to be unaware when people talk to them, but respond to other sounds
  • Getting upset by slight changes in a routine

Why is Autism called Autism Spectrum Disorder? (2020, July 13). Retrieved from https://carmenbpingree.com/blog/what-is-autism-spectrum-disorder/

ADHD: Attention Deficit Hyperactivity Disorder

Attention Deficit Hyperactivity Disorder is the most commonly diagnosed mental disorder in children. It can continue into adulthood as well and is commonly spotted and recognised during the early years of learning when a child is seen to have issues paying attention—this is the most common and obvious symptom. These symptoms are grouped into three types: inattentive, hyperactive-impulsive and combined. You may have heard the term ADD to describe a condition similar to ADHD. The difference is simply that ADD, Attention Deficit Disorder, is an outdated term. ADHD is the current overarching name of the condition. The term ADHD became official in May 2013, when the APA released the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).

Despite the infamous and predominant nature of the disorder, doctors and researchers do not know exactly what causes it, however, reduced dopamine is said to be a factor in it. Some signs or symptoms amongst others that may indicate the existence of the disorder are as follows:

  • Seem to not listen when spoken to directly
  • Fail to not follow through on instructions, fail to finish schoolwork, chores, or duties in the workplace, or start tasks but quickly lose focus and get easily sidetracked
  • Have problems organizing tasks and activities, such as doing tasks in sequence, keeping materials and belongings in order, keeping work organized, managing time, and meeting deadlines
  • Avoid or dislike tasks that require sustained mental effort, such as schoolwork or homework, or for teens and older adults, preparing reports, completing forms, or reviewing lengthy papers
  • Lose things necessary for tasks or activities, such as school supplies, pencils, books, tools, wallets, keys, paperwork, eyeglasses, and cell phones
  • Become easily distracted by unrelated thoughts or stimuli
  • Forgetful in daily activities, such as chores, errands, returning calls, and keeping appointments

Schizophrenia

Schizophrenia is a serious mental disorder that causes patients to interpret reality abnormally. This can range from delusions to hallucinations. Keeping symptoms under control requires lifelong treatment. It usually appears in late adolescence or early adulthood. Schizophrenia can be divided into negative and positive, wherein negative indicates lack of psychosis and positive indicates its presence. Some signs or symptoms amongst others that may indicate the existence of the disorder are as follows[4]:

  • confused speech that is hard for others to understand
  • lack of facial expression
  • lack of emotional expression
  • lack of motivation
  • difficulty concentrating
  • psychosis, such as delusions and hallucinations

According to NIMH, the cause for the disorder is when environmental factors combine with genetic factors. 

Schizophrenia Treatment in Ludhiana, Punjab. (n.d.). Retrieved from https://manashospitals.com/schizophrenia/

Conclusion

Psychological disorders–including but not limited to the ones discussed above–are widely present in a large number of people. They require treatment and care, but above all, understanding. Everyone’s brain is wired uniquely. Certain abnormalities in the wiring that leads to mental disorders are no fault of the person and this is the most important thing to keep in mind while dealing with people who have mental disorders. However, it is important to note that improving mental health opportunities is still an area we need to improve on globally.

Neha Menon, Youth Medical Journal 2021

References

Diagnostic and Statistical Manual of Mental Disorders (DSM–5). (n.d.). Retrieved from https://www.psychiatry.org/psychiatrists/practice/dsm [1]

Autism Spectrum Disorder. (n.d.). Retrieved from https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd/index.shtml[2]

What is Autism Spectrum Disorder? (2020, March 25). Retrieved from https://www.cdc.gov/ncbddd/autism/facts.html[3]

ADHD: Symptoms, Types, Testing, and Treatment. (n.d.). Retrieved from https://www.webmd.com/add-adhd/childhood-adhd/attention-deficit-hyperactivity-disorder-adhd

Schizophrenia: Symptoms, causes, and treatments. (n.d.). Retrieved from https://www.medicalnewstoday.com/articles/36942[4]

Schizophrenia. (2020, January 07). Retrieved from https://www.mayoclinic.org/diseases-conditions/schizophrenia[5]

Categories
Neuroscience

Subliminal Stimuli and its Neurological Affects

By Neha Menon

Published 6:12 PM EST, Fri April 16, 2021

Introduction

Subliminal messages have been used since time immemorial, but researchers are yet to give a very concise explanation of, both, whether it works and if it does, how? In simple words, “any sensory stimuli below an individual’s threshold for conscious perception is called a subliminal message.” (Wikipedia)

Consciousness, put very plainly, is the state of being aware – aware of one’s surroundings, thoughts, emotions and the external & internal environment. On the contrary, the unconscious state of mind is one wherein there lies “a reservoir of feelings, thoughts, urges, and memories that are outside of one’s conscious awareness.”[1] This consciousness is enabled by the part of our brain called the cerebrum, whereas the unconscious actions are performed by the basal ganglia and cerebellum. This concept may be  attributed to Sigmund Freud – Austrian neurologist and the founder of psychoanalysis. The discussion of the conscious and unconscious state of our mind highlights the core topic of this article: subliminal primings or subliminal messages, which were brought to the mainstream media as early as 1957.[2]   However, extensive research and scientific opinions on this subject have only emerged in the recent years. This is discussed in further topics.

Primarily, subliminal messages work by nudging your unconscious. This would imply that by listening or looking at a subliminal message, we are gathering information or getting affected unconsciously. This is why, before we look at the ‘what, why and how’ of subliminal priming, we must understand the theories of the unconscious state of mind, which will give a great deal of insight regarding the direct workings of a subliminal message on the brain.

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“The mind is like an iceberg, it floats with one-seventh of its bulk above water.” — Sigmund Freud.
https://medium.com/achology/the-three-levels-of-human-consciousness-6d9a59fed577

The Unconscious State of Mind

It would be beneficial to understand first that the conscious state of mind is finite. If we were to notice and process (consciously) everything that we see, hear or feel in a day, our brain would be far too overwhelmed and the retention of this information may be compromised. The unconscious, on the other hand, is vast – limitless – to say the least. Everything we see, hear or feel goes into our unconscious but doesn’t necessarily get processed. This means that the way we perceive something may not be the actual reality of it.

Secondly, it is important to note that the brain can only perceive something in the way and form that it first enters our mind. Meaning, imagine a picture, for instance, that could be perceived in two different ways based on how you look at it. Perhaps (as shown in the image below) : an old woman who, if and when the perspective is changed – looks like a young girl. Your brain may be able to identify these two ‘forms’ of the same picture but it will not be able to see both forms at the same time.

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Image credits: public domain

The “How” Of Subliminal Messages

Once we know how the unconscious mind works, we can move on to explore why and how subliminal messages affect our brain neurologically.

In subliminal messages, there are multiple items (audio/video/picture) that require relational processing. This may  be compared to the picture discussed above, which can be seen as two separate images. Relational binding hence calls upon the hippocampus – a complex brain structure embedded deep into the temporal lobe. It has a major role in learning and memory. Hence in this case, it can rapidly store novel relations for a longer term. Usually, it is known that the hippocampus is involved in the encoding and retrieval of consciously perceived information.

“However, growing evidence suggests that hippocampus operates independently of consciousness and that nonconscious relational learning is humanly feasible”[6]

While talking about the direct effects of subliminal stimuli on the brain, they robustly activate certain parts:

Amygdala – It is recognised for its role to process emotions. It is the part of the human brain best known for its ability to drive the ‘fight-or-flight’ response and also plays a vital role in memory. 

Insula – The insular cortex links sensory experience and emotional stimuli. It is also linked with conscious emotional feelings

Hippocampus – It plays a part in memory consolidation: the process of transferring new learning into long-term memory

Anterior cingulate – has been implicated in several complex cognitive functions, such as empathy, impulse control, emotion, and decision-making.

We see that most of the affected parts have a role to play in emotional valence or memory. It is these parts that are activated when your brain is exposed to subliminal messages.

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https://visme.co/blog/subliminal-messages/

Subliminal Messages In The 1900’s

When the history of subliminal messages is regarded, we see that most of them were used in marketing, or advertisements. The following timeline shows some of the important milestones in the history of use and discovery of subliminal messages:

1943 – Subliminal messages were occasionally used on the radio and television programs. [3]   

1990 – Many researches showed little or no link in the subliminal messages and the psychology of the brain, while others started uncovering subtle effects. [3]   

2006 – Studies showed and proved that subliminal messages did work in several advertising scenarios.  [3]   

2007 – Subliminal messages for academic performance were uncovered and studied. [3]  

2010-2015 – Imaging proved that subliminal messages did affect several parts of our brain, including but not limited to the visual cortex and hippocampus[3].   

Other common forms of subliminal messages in recent years are:

  • Images being inserted into the frames of movies, trailers, commercials etc., for an extremely short amount of time in such a way that the brain cannot consciously comprehend it.
  • Audio messages inserted under louder audio messages in order to mask it.

The “Why” Of Subliminal Messages

Subliminal messages and stimuli have been used in several places for several different reasons. 

  • The most common of all, is advertising and marketing. Companies like Coca-Cola show a good example of subliminal messaging for marketing in the late 1900s. Here the words “Buy Coca-Cola” and/or “Buy Popcorn” were flashed into movie reels.
  • For political agendas, like the one in the George Bush campaign in 2000. The opponent, Al Gore, accused Republican campaign managers of including a subliminal message in an attack ad focusing on Gore’s proposed healthcare policies. The word ‘RATS’ was flashed quickly right before the presentation of the word ‘bureaucrats’. 
  • In Disney movies like Aladdin, The Little Mermaid and The Lion King. It is unclear what the agenda for these were, and whether they were intentional at all.
  • In more recent times, subliminal messages have been famously used as auditory sources – melodic rhythms in particular. These claim to be able to change several things in your physical and mental realms; from removing mental head-block to changing eye color or weight. It’s efficiency or lack thereof, is not proved yet.

Conclusion

Exposure to subliminal stimuli have been proved to have certain effects on the human brain through research and experimentation. The efficiency, however, is not ensured. According to a UCL research, subliminal messaging is most effective when the message conveyed is negative in comparison to when it is positive. [7] Certain subliminal stimuli (especially now that the concept has taken pace) may have harmful impacts on the brain. They cannot damage the brain per-se, but can have negative impacts on your subconscious mind.

Neha Menon, Youth Medical Journal 2021

References

Cherry, K. (2020, December 09). The Structure and Levels of the Mind According to Freud. Retrieved from https://www.verywellmind.com/the-conscious-and-unconscious-mind-2795946#[1]

6 Examples of Subliminal Advertising, from Spooky to NSFW. (n.d.). Retrieved from https://www.wordstream.com/blog/ws/2017/10/24/subliminal-advertising [2]

Stern, V. (2015, September 01). A Short History of the Rise, Fall and Rise of Subliminal Messaging. Retrieved from https://www.scientificamerican.com/article/a-short-history-of-the-rise-fall-and-rise-of-subliminal-messaging/ [3]    

Sigmund Freud. (n.d.). Retrieved from https://www.britannica.com/biography/Sigmund-Freud [4]  

Subliminal stimuli. (2021, February 16). Retrieved from https://en.wikipedia.org/wiki/Subliminal_stimuli [5]

Ruch, S., Züst, M. A., & Henke, K. (2016, August 20). Subliminal messages exert long-term effects on decision-making. Retrieved from https://academic.oup.com/nc/article/2016/1/niw013/2757133[6]Ucl. (2018, November 15). UCL study: Subliminal messaging ‘more effective when negative’. Retrieved from https://www.ucl.ac.uk/news/2009/sep/ucl-study-subliminal-messaging-more-effective-when-negative [7]

Categories
Neuroscience

Your Brain Is Built To Forget

By Neha Menon

Published 4:38 PM EST, Sun March 28, 2021

Introduction

The theory of memory, its stages, and mechanisms have been an ever-changing topic of discussion and research throughout the years. However, it has always been known that there exist certain loopholes and gray-areas which causes a related phenomena: forgetting. Through the years of study in cognitive psychology & neurology, the process of forgetting was always treated as an afterthought. In contrast to this, more recent studies contradict decades-old assumptions. Specifically they prove that the brain was, in fact, built to forget. That, in order to remember, forgetting is a crucial step.

Memory

Much is still to be learned about memories; how they are created, accessed and, sometimes, lost. But the little that we do know is important to note before studying the significant phenomenon of forgetting. 

  • When we talk about the process of memory, it is imperative to understand that what we hear, see or learn does not simply go into the brain unedited as a recording. It is, in fact, constructed and reconstructed several times by what we hear or learn after that. 
  • Although we may think that the memory of some people is near-perfect, our active cognitive processing of information ensures that memory is never an exact replica of what we first picked up, learned, or experienced.
  • The physical basis of memory is that these higher intellectual processes are based in the cerebral cortex. “If certain parts of the cerebral cortex are stimulated electrically, there will be recall of experiences.”[1]  It is commonly known that the process of memory entails encoding, retaining, and retrieving information. Other parts that are actively involved in these activities are the amygdala, the hippocampus, the cerebellum, and the prefrontal cortex.
  • Autobiographical memories (personally experienced events) develop in the hippocampus, while the actual encoding of memory takes place through synaptic plasticity wherein “neurons constantly produce new proteins to remodel parts of the synapse, which enables the neurons to selectively strengthen their connections with one another”[2]
  • The crux of the topic is this: “Memory is the means by which we draw on our past experiences in order to use this information in the present.” (Sternberg, 1999).
Memory & The Brain | Where Is It Stored & How Is It Used?
Parts of the brain involved with memory
https://human-memory.net/memory-the-brain/

Forgetting: A function of memory, not a failure of it.

The mechanisms of forgetting have been researched and studied in flies and rodents. One major takeaway from what was learned is the effect of AMPA receptors. AMPA receptors are particular types of receptors found at the synapse of a neuron, and the amount of this receptor in a synapse determines connection strength between neurons. Essentially, the strength between neurons is directly proportional to the effectiveness of the encoding process of some memory.

If the synapse of two neurons has the necessary amount of AMPA receptors, it is a given that the strength between these two neurons is good, and in effect, the memory has been encoded properly. The problem is that none of these AMPA receptors are stable. “They are moved in and out of the synapse constantly and turn over in hours or days.”[2]

Hardt, a researcher, proposed that AMPA receptors can also be removed, which would mean that forgetting is an active process. And if that were true, then preventing the removal of AMPA receptors should prevent forgetting. When this was tried on rats, it seemed as though for the rat to forget, it had to continually destroy certain connections at the synapse. With this, Hardt says, “Forgetting is not a failure of memory, but a function of it”.[2]

Another proposed cause of forgetting was seen by Paul Frankland, a neuroscientist. He discovered that increasing the neurogenesis in mice caused them to forget more. This is, in fact, very ironic and contradictory to what we know about neurogenesis: it is the process by which new neurons are formed. New neurons should ideally mean more capacity to store memory. But the effect of neurogenesis on its proportional loss of memory was explained: “When neurons integrate into the adult hippocampus, they integrate into an existing, established circuitry. If you have information stored in that circuit and start rewiring it, then it’s going to make that information harder to access,” Frankland said.

Humans keep the memories accurate by forgetting | Lunatic Laboratories
https://loonylabs.org/2015/01/09/forgetting-memory/

Conclusion

There are certain other known theories regarding the process of forgetting: dopamine receptors and M.C.H neurons are a few amongst some others. 

Researchers like Ronald Davis believe that the brain employs forgetting and therefore clear out unnecessary pieces of information in order to make retaining other ones easier. This would imply that the brain keeps memories accurate by forgetting other less-important ones. Others also see forgetting as an advantage for the mental flexibility inherent in creative thinking and imagination.[3]

Neha Menon, Youth Medical Journal 2021

References

Chawla, D. S., & Quanta Magazine moderates comments to facilitate an informed, S. (n.d.). To Remember, the Brain Must Actively Forget. Retrieved from https://www.quantamagazine.org/to-remember-the-brain-must-actively-forget-20180724/

Contributors, H. (2009, October 05). Memory. Retrieved from https://health.howstuffworks.com/human-body/systems/nervous-system/memory-info.htm [1]

Gravitz, L. (2019, July 24). The forgotten part of memory. Retrieved from https://www.nature.com/articles/d41586-019-02211-5 [2]
Sheikh, K. (2019, September 19). Scientists Identify Neurons That Help the Brain Forget. Retrieved from https://www.nytimes.com/2019/09/19/science/brain-memory-forgetting-mind.html[3]

Categories
Neuroscience

Your Brain On LSD

By Neha Menon

Published 4:30 PM EST, Fri February 26, 2021

Introduction

LSD (Lysergic acid diethylamide) is one element of a wide ranging group of drugs called psychedelics. The primary use of psychedelics is to trigger “non-ordinary states of consciousness”[6], and to alter several cognitive functions such as perception and mood (Wikipedia). LSD specifically works by triggering hallucinations, hence being known as a hallucinogenic drug. But what exactly does LSD do to the human brain? And how can it potentially be used to ease the struggles of thousands of depressed individuals? 

LSD – A Brief History 

In 1938, Swiss chemist Albert Hoffman synthesized LSD for the first time. The fungus that LSD was taken from is said to cause convulsions, madness, and even death. Fun fact: April 19th is still celebrated as “Bicycle Day” in honor of the famous day on which Hoffman rode his bike home after taking LSD for the first time, and experienced an insane inward “trip.” In 1947, Sandoz Laboratories encouraged the intake of LSD by advertising it to be “a cure for everything from schizophrenia to criminal behavior, ‘sexual perversions’ and alcoholism”[6]  (Wikipedia).

It was soon discovered that as little as 25 micrograms of LSD is enough to stimulate vivid hallucinations. The official ban of this drug in the United States in 1967 shows how widely it was abused–while some used it to escape reality, others (specifically the military) began exploring its potential as a chemical weapon. However, many had begun noticing that the use of LSD caused them severe anxiety and depression, while others reported being unable to feel “normal,” and feeling a sense of disconnection from reality.

How LSD Produces Hallucinations 

Firstly, it is important to understand that LSD works by affecting several nerve receptors, such as the dopamine, adrenergic, and serotonin receptors. The last one is particularly interesting and relevant to the functioning of this drug. There is a type of serotonin, known as 5-HT2A, that has a role in the visual cortex. When inside you, LSD affects this particular cell surface receptor. This is the primary cause for the “trippy” visuals.

LSD study reveals why acid trips last so long | Drugs | The Guardian
Photograph: Fredrik Skold/Alamy

The Inner-Workings of LSD 

How exactly LSD affects the brain, and why it gives the results it does, have been subjects of study throughout the years. Researchers from Imperial College London, along with Beckley Foundation, have successfully visualized these effects, and the findings were published in Proceedings of the National Academy of Sciences (PNAS). The following are some major takeaways:

  • Although visuals images are typically processed in the visual cortex, several other brain areas contribute to processing visuals when your brain is on LSD. 
  • In Dr. Robin Carhart-Harris’ words: “We observed brain changes under LSD that suggested our volunteers were ‘seeing with their eyes shut’; as in, they were seeing things from their imagination rather than from the outside world.” [2] 
  • The research group also observed that, despite the volunteers’ eyes being closed, the part of the brain involved in visual processing was accompanied by many other parts of the brain. Furthermore, the size of this effect correlated with volunteers’ ratings of complex, dreamlike visions, meaning that complexity was directly proportional to the involvement of other parts of the brain. 
  • Visuals are processed in the visual cortex, movement in the cerebellum, and hearing in the auditory cortex. Notice that these are individual and separate areas of the brain. While on LSD, the level of ‘separateness’ is lower, and the processing of several functions may overlap one another, or unify. 
what does it feel like on an acid trip?

How LSD May Potentially Treat Mental Illnesses

After learning how LSD drastically alters one’s state of consciousness, how is it that this potent psychedelic can be used in treating depression? A lot more research is required to fully understand this (since, as seen in the above image, depression is a potential side effect of the extreme use of LSD), but one of the known  methods is: micro-dosing. People such as Ayelet Waldman–an author who had personal experience with the subtle effects of LSD under smaller doses–believe micro-dosing can help a depressed individual feel better while avoiding hallucinations as a side effect. It may also provide enough of a sense of disconnection from reality to make one’s intrusive thoughts less overwhelming. It is important to note that LSD depression therapy is only available to those who sign up for clinical trials.

Dangers & Disadvantages of LSD Treatment

The effects of LSD–both negative and positive–have yet to be researched thoroughly enough. In my opinion, the use of the drug to cure depression is very risky. Different drugs produce different levels of compatibility amongst a large, diverse population. And, in this case, the difference between a ‘good’ versus a ‘bad’ trip may be too big of a risk for someone with an already compromised state of mental health to undertake. Serious side effects such as increased anxiety, or potentially violent depressive episodes due to flashbacks from bad experience with the drug are to be wary of.

Note: LSD is known to have several side effects on the brain, both short term and long term. It is illegal to sell or intake LSD in most places, so self-treatment or ingestion is not recommended. 

Neha Menon, Youth Medical Journal 2021

References

Foundation for a Drug-Free World International. “The History of LSD – Acid, Albert Hoffman & Timothy Leary – Drug-Free World.” Foundation for a Drug-Free World, www.drugfreeworld.org/drugfacts/lsd/a-short-history.html. Accessed 21 Feb. 2021. [1]

Neuroscience News. “This Is Your Brain on LSD.” Neuroscience News, 12 Apr. 2016, neurosciencenews.com/lsd-neuroimaging-visual-cortex-4023. [2]

Sample, Ian. “Why Does LSD Make You Hallucinate?” The Guardian, 22 Feb. 2017, www.theguardian.com/science/2006/feb/25/drugs.thisweekssciencequestions. [3]

The Recovery Village. “LSD and Depression.” The Recovery Village Drug and Alcohol Rehab, 15 Jan. 2020, www.therecoveryvillage.com/lsd-addiction/related-topics/lsd-and-depression. [4]

Wendorf, Marcia. “The Resurgence of Psychedelics: Magic Mushrooms and LSD.” The Resurgence of Psychedelics: Magic Mushrooms and LSD, 9 Aug. 2019, interestingengineering.com/the-resurgence-of-psychedelics-magic-mushrooms-and-lsd. [5]Wikipedia contributors. “Psychedelic Drug.” Wikipedia, 17 Feb. 2021, en.wikipedia.org/wiki/Psychedelic_drug. [6]