Chapter 1

Embracing Brain Health Fundamentals

IN THIS CHAPTER

Knowing what a healthy brain means

Finding out about brain health models

Understanding how healthy brains perform best

Introducing brain health disorders

Having a healthy brain is about more than avoiding mental health problems, diseases, or dementia; it's about thriving, feeling good, and performing at your best.

Some people think being healthy means not being sick, but the World Health Organization sees it differently. They say health is all about "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity." This definition also means that health isn't just about eating veggies or keeping cholesterol in check. It's a more holistic view, nicely aligned with what we often call well-being.

Let's be real: Some brain health conditions are out of our control, due to genetics or plain bad luck. But don't worry! You can do plenty to lower your risk or improve symptoms for many diagnoses, diseases, and quirks. Remember, being healthy isn't just about dodging illness; it's about making the most of your brain health, no matter your diagnosis.

Coming to Grips with the Biopsychosocial Model of Health

To truly understand brain health, you need to consider the biopsychosocial model, which looks at the interplay between biological, psychological, and social factors.

Taking a biopsychosocial approach acknowledges that your health is influenced not only by your biology (such as genes, hormones, muscle strength, or gut health) but also by your psychological state (such as your stress levels and mental health) and your social environment (including relationships and community).

We like to put the brain in the middle of the biopsychosocial model, calling it the bottom-up, outside-in, top-down model of the brain:

• Bottom-up elements are the biological or physiological determinants of brain health, development, and aging. The elements include genes, hormones, the immune system, nutrition, exercise, sleep, and the constant streams of data about what's happening inside your body, some of which you're conscious of (such as a full bladder, sore back, or kicking baby) and other factors you're unaware of (such as hormone levels or gut pH).
• Outside-in elements are outside but make their way in by way of our senses (what you see, hear, smell, touch, and taste). Outside includes your social circle, the culture you grew up in, the built and natural environment, current circumstances, and external stressors.
• Top-down elements include what you think of as your mind - your conscious thoughts, emotions, personality, language, expectations, and belief systems.

Our version of the biopsychosocial model may help you understand the complex and dynamic nature of brain health.

Understanding How a Healthy Brain Works

To maintain a healthy brain, it's helpful to understand its main duties. Your brain is responsible for perceiving the world, interpreting biological signals, guiding behavior, feeling emotions, thinking and reasoning, socializing, controlling movement, storing and retrieving memories, and maintaining homeostasis (a stable internal state). Here are a few ways a healthy brain performs when it's in peak condition:

• Perceiving your world: Your brain constantly processes sensory information from your environment, including everything you see, hear, taste, touch, and smell. The brain's ability to perceive and interpret sensory data enables you to navigate and understand the world. This sensory processing is vital for learning, memory, and everyday functioning.
• Interpreting biological signals: Your brain receives and interprets signals within your body, such as hunger, thirst, and pain. These internal signals are crucial for maintaining homeostasis and responding to your body's needs. Understanding these signals helps you manage your health and well-being more effectively.
• Guiding your behavior: Your brain is the command center that guides your actions and decisions. It integrates information and plans, and executes behaviors to help you achieve your goals. Whether you're performing daily tasks, solving problems, or pursuing long-term objectives, your brain's executive functions are at work.
• Feeling emotional: Emotions are an integral part of your brain's function. They influence your thoughts, behaviors, and interactions with others. Emotional health is about recognizing, understanding, and managing your feelings. A well-regulated emotional brain contributes to resilience, mental health, and overall well-being.
• Thinking and reasoning: Cognitive functions such as thinking, reasoning, and problem-solving are essential for navigating life's challenges. Your brain's ability to process information, make decisions, and learn new skills is fundamental to personal and professional growth. Cognitive health ensures that you can think clearly, remember information, and stay mentally agile.
• Socializing and interacting: Humans are inherently social beings; our brains are wired for social interaction. Effective communication, empathy, and relationship-building are all functions of a healthy brain. Social connections provide emotional support, reduce stress, and enhance cognitive function. Maintaining a social network (not online!) is crucial for brain health.

Uncovering Common Brain Disorders

The Diagnostic and Statistical Manual of Mental Disorders (DSM) is the standard mental disorder classification worldwide. The current fifth edition (DSM-5) categorizes brain health symptoms, disorders, and diseases by number. Specialists make a diagnosis by carefully using a combination of observations and assessments to identify these conditions.

The language you might hear used to discuss these neurodevelopmental disorders has shifted in the past few decades. They are no longer solely defined as disabilities or diseases. Instead, there's a growing acknowledgment of neurodivergence - a term that appreciates these conditions as variations in how brains work.

Understanding neurodevelopmental disorders

Neurodevelopmental disorders are conditions in which the typical wiring of the brain and nervous system is altered during brain development, either while growing in the womb or during the first two years of life. They affect how the brain develops in childhood and adulthood.

Attention deficit hyperactivity disorder (ADHD)

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental condition often identified in childhood and frequently carried into adulthood. Boys are three times more likely than girls to be told they have ADHD. This doesn't mean girls are less prone to the illness. It may just be that ADHD symptoms in girls differ.

Attention is a complex cognitive process that allows you to tune into specific information in your environment while tuning out other stimuli. At the core of attentional processes is the prefrontal cortex (PFC), which acts as the conductor, directing your focus. Also involved are neurotransmitters such as dopamine and noradrenaline, which signal to the PFC to dial up or dial down its neural activity. The right balance of loud versus quiet neural activity enables you to organize your thoughts, prioritize tasks, and keep track of time.

In ADHD, this attention system operates differently. The PFC is less efficient due to variations in neurotransmitter activity. It's like having a less responsive conductor or instruments in an orchestra that ignore the conductor and continue playing too loudly.

Autism spectrum disorder

Autism spectrum disorder (ASD) is a developmental condition that affects communication, behavior, and social interaction. Rates vary globally, which most likely reflects differences in diagnoses and reporting, but it's estimated that 1 in 100 people are on the autism spectrum. About three to four times as many males than females have a diagnosis. This ratio is a result of both biological differences and gender-based diagnostic criteria that may overlook autism in girls.

The neurobiology of ASD involves complex interactions between genes, brain structure, and function. There is no way to scan someone's brain and diagnose them with autism based on obvious differences. Instead, ASD is characterized by subtle differences in network connectivity and processing, especially in regions that process information about social cues.

Both environmental factors and dozens of different genes contribute to ASD risk. Some research suggests alterations in neurotransmitters and synaptic pathways emerge very early in brain development, when the baby is still in utero. Early neurogenesis (neuron cell birth) and neuron migration can have major effects on a wide range of symptoms.

Dyslexia

Dyslexia is a specific learning disorder with a neurological basis. It's best characterized as a persistent difficulty with reading and spelling. Whereas one in five children struggle with literacy at school, about one in ten people meet the criteria of dyslexia. In a school setting, it seems to be more visible in boys, which results in earlier and...