Showing posts with label Sensorimotor. Show all posts
Showing posts with label Sensorimotor. Show all posts

Interoception and exteroception

[Concepts in Sensorimotor Research]

Interoception and exteroception are two types of sensory perception.

Interoception refers to the sense of the internal state of the body. It helps us understand and feel what's going on inside our bodies, like feeling hungry, thirsty, or perceiving our heartbeat. Interoceptive awareness contributes to emotional regulation and self-awareness.

Exteroception refers to the perception of the external environment through our senses like vision, hearing, touch, taste, and smell. These senses help us navigate and interact with the world around us.

Research findings  in autism:

Autistics often exhibit differences in sensory processing, which may include atypical interoceptive and exteroceptive perception. Findings (examples below) suggest that atypical interoceptive and exteroceptive processing may be significant factors in understanding the behavioral and sensory symptoms in individuals with autism.
  • This review explores the role of oxytocin in interoception and its potential implications for autism. The authors propose that atypical interoceptive processing, potentially linked to altered oxytocin functioning, could contribute to the social and emotional difficulties experienced by autistics. (1)
  • This study found that adult autistics exhibited significantly lower interoceptive awareness compared to NT adults. The authors suggest that this might be related to the difficulties in social and emotional processing seen in autism (2).
  • This review discusses various neurophysiological findings in sensory processing, including exteroception, in autistics. The authors highlight that altered sensory processing may contribute to the core features of ASD, such as social communication and repetitive behaviors (3) 

Oddball Paradigm

The oddball paradigm is a cognitive research method involving the detection of infrequent, deviant stimuli within a series of standard stimuli, used to study sensory processing, attention, and cognitive control. It is widely used in autism research as it helps identify atypical neural and behavioral responses.

PlainSpeak: The oddball paradigm is an experiment where people detect unusual items in a series of regular items. It's used in autism research to understand how people with autism process information differently.


Alexithymia and Autism

Alexithymia is characterized by difficulty in recognizing and expressing one's emotional experiences.

The term was first used in the 1970s by psychotherapist Peter Sifneos to describe a group of people who had difficulty expressing their emotions. They may also be more prone to stress-related issues and have difficulties coping with stress in general.


Studies find the prevalence of alexithymia in autistics to range from 50% to 66% compared to a 10% prevalence in the neurotypical population (1,2).
  1. Alexithymia in autistics has been associated with several negative outcomes.Social communication difficulties: Difficulty expressing emotions and interpreting the emotions of others, can interfere with social communication; which may be particularly pronounced in autistics, who already experience social communication difficulties (3).
  2. Reduced quality of life due to the negative impact on social relationships (4)
  3. Increased anxiety and depression: One study found that alexithymia was a significant predictor of depression in autistic adults (5).
  4. Greater risk for negative outcomes: In a longitudinal study of autistic children those with higher levels of alexithymia were found to have a higher risk for negative outcomes such as anxiety, depression, and behavioral problems over time (6).

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A Plain Language Version

What is Alexithymia? Alexithymia is when someone has a hard time recognizing and talking about their own emotions. They might also find it tough to cope with stress and are more likely to have stress-related issues.

History of Alexithymia The term "alexithymia" was first used in the 1970s by a psychotherapist named Peter Sifneos. He noticed that some people had difficulty expressing their emotions and gave this condition a name.

Alexithymia and Autism Studies show that alexithymia is much more common in autism. About 50% to 66% of autistics have alexithymia, compared to only about 10% of people without autism.

Effects of Alexithymia in Autism

  1. Social Communication Difficulties: Autistics with alexithymia have an even harder time expressing emotions and understanding others' emotions, making social interactions more challenging.
  2. Reduced Quality of Life: Having trouble with social relationships can lower overall happiness and satisfaction in life.
  3. Increased Anxiety and Depression: Research shows that alexithymia can lead to higher levels of anxiety and depression in autistic adults.
  4. Greater Risk for Negative Outcomes: In a long-term study of autistic children, those with higher levels of alexithymia were more likely to experience anxiety, depression, and behavioral problems as they grew up.

Understanding and addressing alexithymia in autism is important for improving social interactions, mental health, and overall quality of life.


Noise Cancelling Headphones and Autism

Noise Cancelling Headphones are often seen as the solution to sensory overstimulation in autistics. 
Pop on a pair of headphones. And Voila, the autistic problem is solved like magic (sarcasm intended).

Are they really the solution they are touted to be? The answer may surprise you. 

Taxonomy of Sensory Differences in Autism

 



The authors (Vanderbilt study) propose a hierarchical taxonomy to describe and refer to various sensory features of autism, which will help researchers to better understand the nature and impact of the sensory differences of autism and place future research targets at appropriate levels of analysis.

The 5 levels of proposed taxonomy are.
 

Peripersonal Space

Peripersonal space (PPS) is the region of space immediately surrounding the body, where sensory inputs from multiple modalities are integrated to guide actions and protect the body. In autism, alterations in PPS processing may contribute to challenges in sensory-motor integration, social interactions and spatial navigation. This area of research, which I am exploring in graduate school, holds promise for interventions at the individual level and disability accommodations at the societal level. Stay tuned for more in-depth posts on this topic.

PlainSpeak: Peripersonal space (PPS) is the space right around our bodies that helps us sense and respond to things nearby. For autistic individuals, differences in how this space is processed might explain some of the sensory and social challenges they face and how we navigate the space around us. I'm studying this in grad school and will be sharing more insights in upcoming posts.


Related Posts on [PPS] [Peripersonal Space]

Oromotor skills in Autism


Based on review of research published between 1994 and 2022 on oromotor functioning in autistic individuals, 

key takeaways: 
  • Oromotor functioning plays a foundational role in spoken communication and feeding.
  • 81% of included 107 studies report a significant oromotor challenges related to speech production, nonspeech oromotor skills, or feeding 
  • Studies used various methods to investigate oromotor functioning in autistics
    • Behavioral measures -  tasks such as tongue protrusion, lip closure, and oral diadochokinesis. 
    • Parent report measures - questionnaires and interviews. 
    • Medical record review - examining medical records for information on feeding / swallowing difficulties. 
    • Neuroimaging techniques -  fMRI & MEG.
  • The findings suggest that oromotor challenges are common in autistics, but more research is needed to better understand the nature / extent and their impact on communication and feeding.
Some limitations of this paper include
  • numerous inclusion and exclusion criteria, which may have excluded relevant studies eg: non-English publications, pre 1994 studies etc
  • wide variation in studies re sample characteristics, behaviors analyzed, and research methodology, which makes it difficult to draw definitive conclusions. 
  • did not include a meta-analysis, which would have allowed for a quantitative synthesis of the findings across studies. 

Maffei MF, Chenausky KV, Gill SV, Tager-Flusberg H, Green JR. Oromotor skills in autism spectrum disorder: A scoping review. Autism Res. 2023 Apr 3. doi: 10.1002/aur.2923. Epub ahead of print. PMID: 37010327.

Anxiety in ASD

Went for a guest lecture by Dr. Trenesha Hill, Asst Prof at U Nebraska Medical Center. 



What caught my attention was atypical/autistic anxiety (vs non-autistic-anxiety) as being related to core characters of Autism. Especially the suggestion that hypersensitivity (ie: sensory differences) was a main factor distinguishing autistic-anxiety from non-autistic anxiety. Totally worth investigating the sensory aspect which I wish this study had done. 

Constant Overload


Being bombarded by the sensory system
A constant overload, it never ends
Sensory overwhelmed, a feeling of prison
Trapped in my own mind, with no friends.

Poor somatosensory body mapping
A constant confusion, a foggy haze
I struggle to understand my own body
A feeling of being lost, in a daze

Words get stuck, inside my head
Apraxic, struggles to speak
A feeling of frustration, so very unique
As talking eludes me, instead

It can be a struggle, to navigate
This world that's full of sensation

I need to find a way
… with determination

The brain is a Giant Prediction Machine

Poem follows Prof Mark Wallace's comment in class "The Brain is a giant prediction machine" after a discussion on the growing popularity of Bayesian Statistical Models in research. 


The brain is a giant prediction machine

Bayesian model-like, it constantly schemes

Past experiences and memories in its grasp

Current sensory input, processed in a flash.

 

TBI Regressive Autism

Ameliorating Hemianopia with Multisensory Training (Rowland et al., 2023)

Quick Summary of paper . An  visual-auditory stimulation therapy was used on two older males  who has loss of vision in the left hemifield (hemianopia). The cause was brain trauma (TBI) rather than lesion.  Prior to joining the study both had been referred to PT and OT as rehabilitation measures. 
  • 64 year old JM joined the study 14 months after stroke  (2 infracts)
  • 74 year old CW joined the study ~18 months after 1 infract (better sighted field compared to JM). 
  • Therapy took place over 8 months /10 sessions 
The results were dramatic. Both patients recovered the ability to detect and describe visual stimuli throughout their formerly blind field within a few weeks. They could also localize these stimuli, identify some features, and perceive multiple visuals simultaneously in both fields. (more detail on paper here link)

Relating all this back to Autism
So impressive about being able to restore sight in a matter of 8 months, given therapy was started 14-18 months after infract and not immediately and it was in older adults. 

Why is regressive autism not thought to be TBI at 18 mo, where there is a sudden loss of learned skills. 
  • If TBI --> can those lost skills not be regained through targeted therapy. If you can restore skills in 60-70 yr old, should be able to, in a younger more plastic brain. 
  • If TBI -->  is this related to CW & JM having practice with vision for 60-70+ years vs toddlers who only have practice with the skills for 18 mo.
Rethink Traditional Therapies
  • CW & JM  had PT/OT for 14-18 mo before joining study; implication these therapies not that useful for regaining lost skills. 
  • Autistics kids are in insane amounts of therapy (childhood stuffed with ABA/speech/OT every waking hr with little advances to show for it other than the $$$ spent and lots of career advancement for therapists). 
  •  Maybe we need rethink early childhood therapy to be more targeted to restore lost skills. Even regaining that level of lost skills improves quality of life, let alone moving beyond.


Apraxia, dyspraxia, oral-motor apraxia, Aphasia

[Concepts in Sensorimotor Research]

Pretty much every SLP I've been to over the years, has mentioned these terms. So what exactly are they. 

Apraxia, dyspraxia, and oral-motor apraxia are all related to deficits in motor planning and execution, but they differ in their specific manifestations and underlying neural mechanisms.

Stimulus Value Gates Multisensory Integration

[Concepts in Sensorimotor Research]


Application to Autism. 

The advantage of a good filtering system is less getting overwhelmed by your sensory environment in the real world, but the disadvantage was that you could lose out on critical information. This almost automatic value-based filtering ability is, I think, an issue many autistics like me struggle with. But even with extensive experience, value-based filters could vary around task domain, context-specific or even things like predictability.  Which is still, i think, why we still face challenges in trying to understand what exactly is going on in the non-neurotypical populations. 




Bean, N. L., Stein, B. E., & Rowland, B. A. (2021). Stimulus value gates multisensory integration. European Journal of Neuroscience, 53(9), 3142-3159.



Summary of the paper we discussed in my Multisensory Integration seminar this week. 

Synesthesia and Autism

[Concepts in Sensorimotor Research]

Paper was for my Systems Neuroscience Class this semester was on Synesthesia and Autism. 
(I got an A+ both for this essay and the final grade for the course.)

Instructor Feedback: you wrote an excellent essay! Your essay was engaging to read and provided compelling insight into synesthesia and autism. You succeeded to find intriguing papers at each level of understanding and used those references effectively. The concise way of writing reveals a true talent to distill the key messages from complex papers from (very) diverse fields and to use them for your argument. This was overall very impressive to see! you wrote an excellent essay ! Overall, we grade your essay with an A+ Keep up this good work.


Understanding Neuroception and Its Importance in Autism

PlainSpeak. In Plain Language for the Lay Reader

Have you ever walked into a room and immediately felt comfortable or, conversely, felt uneasy for no apparent reason? This instinctive response is part of what's called "neuroception." Neuroception is a term coined by Dr. Stephen Porges that describes how our brain and nervous system unconsciously scan our environment to assess whether we are safe, in danger, or facing a life-threatening situation. This process is crucial because it helps us decide how to react, even before we're fully aware of what's happening.

For people with autism, neuroception can work a bit differently. Many autistic individuals have heightened sensitivity to sensory experiences, such as bright lights, loud sounds, or crowded spaces. Because of this heightened sensitivity, their nervous system might misinterpret these benign environments as dangerous or threatening, leading to feelings of anxiety or discomfort. This is why you might notice some autistic people avoiding certain places or situations—they are simply responding to what their body perceives as a threat. This reaction is sometimes linked to a phenomenon called "hostile attribution bias," where individuals are more likely to interpret ambiguous situations as having hostile intent. 

Imagine someone accidentally bumps into you. While many might see it as an accident, someone with hostile attribution bias might think it was done on purpose. In autism, this bias can be heightened due to the unique challenges autistic people face, such as difficulties in interpreting social cues or a history of negative social experiences like bullying or exclusion. These experiences can make it harder for them to trust others and more likely to perceive interactions as threatening.

Understanding both neuroception and its link to hostile attribution bias is essential because it helps explain why some autistic individuals might find everyday situations challenging. It also highlights the importance of creating environments that feel safe and comfortable for everyone, especially those with sensory sensitivities. By being aware of these needs, we can help reduce stress and improve the well-being of autistic individuals.

Autistic Burnout



What is it?

Autistic burnout is a term used to describe a state of physical, emotional, and mental exhaustion.  
Autistic burnout can affect the ability to function in daily life, and may be accompanied by symptoms such as depression, meltdowns, anxiety, and executive dysfunction.

Causes
It is a result of prolonged exposure to stressors, such as sensory overload, social demands, and other challenges. 

O Body Where Art Thou

In the Daily Californian, 2 years ago


The lack of Body Awareness or inability of the brain to form a Body Schema is a little known phenomenon in autism. I attempt to explain the neuroscience. 

This is the ninth of my series of 10 articles for my weekly opinion column "The Person Inside" for the Daily Californian. 
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Headline: O body, where art thou?


My hands repeatedly go up to my face, down to the arms of the chair and then back to my lap. My leg and my body keep making small movements. The girl sitting next to me in the lecture hall looks askance at me several times because I appear to be constantly fidgeting. 


The lecture begins, and the picture of the somatosensory map in the brain flashes on the screen, followed by other neuroscience concepts such as mirror neurons. My brain, ears and eyes all perk up in interest. 


Even as I am sitting there listening to the lecture, my mind is busily trying to extrapolate the lecture material to what is currently known about the neuroscience of autism and how it plays out in my life every day, since I am an individual with autism.  


I am especially intrigued by the body map that the brain forms of the different parts of the body in space and time. My mind tries to pull in strings of thought and form a web of understanding as I ponder whether this body map underlies many of the challenges we autistics face. By linking  the neuroscience of autism with observations of my functioning, I am better able to understand my everyday challenges.


You see, for a subset of autistics like me, the brain is not able to form a proper map or body schematic. I can at times feel like parts of my body are missing and that I am not grounded. 


My body adapts through movement. For example, the brain asks the hand where it is, and a connection is formed when the hand moves. The brain is now able to map the hand in its body schematic. But these connections are temporary, which means that if I sit absolutely still for too long in the lecture hall, I may just fall asleep. What other students see are the constant impulsive body movements.


I also tend to rely on vision a lot to help me know where my body is. When I see my leg, my brain registers its presence in my body map. I don’t like to close my eyes during the day because I may lose track of my body. 


For my brain, it’s like looking at a fun house mirror that gives a very different image of you every time you look into it. The image in the mirror is what you are and not who you think you are. 


I tend to use the presence of people around me to help keep my body space organized and keep me grounded. I would feel lost and helpless in a large room with no people. Touching someone or someone touching me even very lightly can help my body parts feel connected to each other and makes me feel grounded.


I think about the slide on mirror neurons from lecture. Mirror neurons in the brain activate when you see another person perform an action — it’s almost like you yourself were performing that action. Mirror neurons are thought to be linked to perception, language ability and even empathy. 

Many professionals believe that there is a delay in the formation of mirror neurons in autistics like me. I wonder if that is because of my imperfect body map, since I am not able to repeat the same neural pathways as many times as non-autistics can. 


I try to pull in more strings of neuroscience, such as apraxia, into this body map puzzle that I am pondering. Apraxia is the difficulty with complex purposeful movements needed for everyday life, such as speech. It is possible that my imperfect body schema contributes to the apraxias that I and many other autistics face.

 

I attempt to straighten out a string that’s been hanging loose on my web of understanding. It’s a catch-22 when you factor in sensory input from the environment. I believe that my sensory input from the environment has to be uniform to form a good body schematic. At the same time, I need to have a good body schematic to interact well with the environment. But I don’t have a good body map, so the sensory environment can be overwhelming and intense for me at times. 


I leave my lecture that day feeling very contemplative as I walk down Oppenheimer Way. My web of understanding still feels somewhat incomplete. While I am excited at all the progress that has been made in understanding the neuroscience of autism, I can only hope that solutions will also follow soon — ones that will help us autistics have a better life.  


First Transitions


Exactly 2 years ago

In "First Transitions", I explain the rigidity and difficulty with transitions that can be characteristic of autism
This is the fourth of my series of 10 articles for my weekly opinion column "The Person Inside" for the Daily Californian. 
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Headline: First transitions


The first semester at a vast university such as UC Berkeley is hard for most students. We all fear the unknown, which brings about its own set of anxious thoughts. When you factor in my type of autism challenges, the process is even more nerve-racking.


We autistics fundamentally have difficulty with handling transitions. A transition is like a doorway: The other side is full of potential unknowns, and our unpredictable autism bodies may not cooperate with us even if we have crossed this doorway before. It’s the idea of change itself in addition to the actual change that comprises transition. The doorway latches on to our anxiety. 


As a child, I really did have a problem entering a building or a classroom. Even now, I rush through physical doorways. The metaphorical doorways for me now are the transitions that occur in everyday life, at college, at home and especially during travel. Interactions with people, trying new food, navigating the campus walkways and buildings all involve crossing a doorway.


Last fall, a day before Golden Bear Orientation, or GBO, the Disabled Students’ Program, or DSP, had thoughtfully organized its own all-day event at Zellerbach Auditorium. But within half an hour of the program, I was completely overwhelmed at the thought of all the transitions I would potentially have to face. I rushed out and sat in the lobby for almost two hours before attempting to go back in.


GBO was a hectic eight-day program with events and discussions that often started at 9 a.m. and ended at 11 p.m. I was surprised that I was able to handle most of them as well as I did. I think what helped was that I was able to return to Zellerbach Auditorium that first day, even if I had to miss two hours, rather than give up and go home — that gave me confidence. 


I had to stand in line outside Memorial Stadium for more than three hours on the first day of GBO, but I still went in. The incoming class was breaking the Guinness World Record for the largest human letter C. The systematic immersion at GBO helped prepare me for the semester.


Then came the first day of classes. I was in Psychology C19: “Drugs and the Brain,” which is a popular class — there must have been about 800 students in Wheeler Auditorium that day. I was a nervous lone figure right at the back, very close to the exit, ready to bolt anytime. But at the same time, part of me was absolutely thrilled to be there. 


There is really no other way of handling transitions than systematic desensitization — repeatedly walking through the doorway and thinking through the steps before going in to reduce that unknown factor.

I sat in the same seat at the back of Wheeler Auditorium for nearly half the semester before moving up row by row. I made it all the way to the fourth row by the end of the semester. 


I also realized that a large class offered lots of anonymity, which was a perfect cover for my offbeat autism mannerisms. There was enough ambient sound to cover any noise I was making. I actually ended up really liking Wheeler Auditorium. It is also quite thrilling to be learning in a classroom that held a Nobel Prize Ceremony. 


The first semester of college was tough, with its innumerable transitions, and it took a lot of kickstarts to get me going. I had introduced myself to my professors via email but it took me more than half the semester before I physically made it to their office hours just to say “Hi.” 


Taking anticipatory steps when possible really helped me. For instance, I worried about how a nonverbal individual like me would participate in a debate during one of my discussion sections. But I finally took on the role of delivering the opening statement for my team — that way, I could prepare ahead of time and let the text-speech app on my iPad be my voice. 


My exams are at a different testing site and in a room that was unfamiliar to me. DSP Proctoring took note of my concern and let me preview the exact room at Moffitt Library a few days prior to my first midterm. They also made sure that I was given that same room for all my exams last semester. 

Life is going to be full of transitions for us autistics. The only way to move forward is to proactively seek transitions.


This semester, I have sought new doorways — writing this opinion column for The Daily Californian, for example, also entails attending staff meetings and editing sessions. I hope I can continue to attempt more doorways and become more at ease in stepping outside my comfort zone.





Sensory Walkabout

Two years ago  was the third of my series of 10 articles for my weekly opinion column on Autism ("The Person Inside") for the Daily Californian, 
 

In "Sensory Walkabout" I write about the way many of us autistics experience our environment in quite a different and quite "extra-ordinary" way. 
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Headline: Sensory walkabout 


I have a rather curious relationship with my environment. You see, my particular brand of autism is accompanied by sensory dysregulation, which means that I often experience my environment in a different and quite extraordinary way.  


A walk through Sproul Plaza is a testament to this unusual relationship. For many, Sproul Plaza is usually a fun and lively place to walk about.


Booths line either side of the Sproul walkway, promoting the various clubs and activities on campus. Musical groups on the steps of Sproul Hall, outside The Golden Bear café and under Sather Gate entertain passersby. A food delivery Kiwibot meanders through the crowd on a mission to feed a hungry student. Students protest near Sather Gate to make their voices heard. Vibrant energy rolls off the 200 or so chattering students milling around. 


But my unregulated sensory system has a different take. I can hear conversations and music from near and far, except they are all at the same volume. I try, unsuccessfully, to filter through this deafening noise and focus on the music nearby. It’s like walking into a party and hearing all the conversations at once and being unable to focus on just one. 


My senses cross over where my eyes can smell and feel, not just see. My eyes can feel the texture of the blue canvas that cover the booths. The white text on the blue canvas feels abrasive on the cool blue, and the canvas moves like a sine curve in the wind.


A student walks quickly by me, carrying a small blackboard easel. The words “Know your ...” are chalked on the board. I want to read but the rest is lost as she scurries right past.  


The Kiwibot looks like a little dog — I want to touch it; I feel compelled to pet it. I reach down, but it just continues on. When I go behind it, it stops and simply stands there. I have a fleeting thought — did I just break the bot?


All these observations — and more — have happened in the space of less than a minute. Hundreds of minutiae flash through my senses. 


I actually love the energy of Sproul Plaza. But my body is reeling and overwhelmed from trying to process it all. This kind of sensory bombardment is both exhausting and exciting for individuals like me, whose systems often struggle to cope with it.  


For most people, the reliance on your sensory system for daily functioning is so automatic that you don’t even think about it. But most people have an inbuilt coping mechanism by way of filters. It requires some effort, but most of you are able to filter out noise and distractions so that you can focus on only what you want to see, hear or do.


But for people like me, these filters are less than efficient. Even the autism meltdown can be the result of sensory overload.


A sensorily disorganized body like mine comes up with its own set of coping mechanisms to drown out the sensory overload. These mannerisms are called “stims,” or “self-stimulatory behaviors” in autism. Flicking your fingers helps filter incoming lightwaves. Verbal noises can be an attempt to drown out external sound. 


But stims that start off as a coping mechanism can also become habits that are hard to kick and look potentially inappropriate as we grow older.


What other students see is an individual who is constantly fidgeting, with an awkward gait and a bunch of offbeat mannerisms. I am aware of standing out, which adds to my anxiety and makes me appear to stim more. 


The skin is the largest sensory organ in the body, so there is sensory input coming in literally from head to toe. It is both agony and ecstasy. 


On the flip side, people like me pick up so many more cues compared to our typical peers, which makes our powers of observation that much more astute. The outward body may not exhibit it, but our minds are thinking, observing and inferring constantly. 


Our atypical sensory system actually works to our advantage in the field of academics, especially in critical thinking and analytical skills. We have a lot to contribute to society since  thinking out of the box is really second nature to us.


We notice things at the gross and subtle levels, even changes in energy levels. When we truly love something and are happy, we enjoy it at a different sensory level — to the point of bliss, at times. The rhythm of a waterfall can, for instance, touch the very soul. It is a heady sensation. 


Even as I try to cope with a body that is often at odds with the environment, I also experience my environment in a most amazing and extraordinary way.



O Body, Where Art Thou?



The lack of Body Awareness is a little known phenomenon in autism. I attempt to explain the neuroscience. 

This is the ninth of my series of 10 articles for my weekly opinion column "The Person Inside" for the Daily Californian.