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HOOKED. THE BRAIN What Neuroscience Can Teach Us. For the American Association of Christian Counselors. Joe McIlhaney, MD Founder / CEO Medical Institute for Sexual Health. Mission of Medical Institute for Sexual Health. Advancing wholeness by empowering optimal sexual health.
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HOOKED THE BRAIN What Neuroscience Can Teach Us For the American Association of Christian Counselors Joe McIlhaney, MD Founder / CEO Medical Institute for Sexual Health
Mission of Medical Institute forSexual Health Advancing wholeness by empowering optimal sexual health Medically Accurate Research Influencer-Focused Leadership --------------- Whole-Health Education ----------------------------------
Learning Objectives • 1. Describe adolescent brain development and maturation. Discuss the role of the prefrontal cortex in decision-making and the time course of frontal lobe development • 2. Explain how experience affects the brain’s developing physical structure. • 3. Explain how neurohormones affect our emotions and our actions. • 4. List the patterns of healthy and unhealthy brain molding.
Learning Objectives (Contd) • 5. Define sex and the “hook up culture” and how it affects relationships and emotions • 6. Discuss the implications of this information for caring adults, counselors and therapists.
The Brain • Three pounds • 10 billion neurons • 100 billion support cells • 100 trillion connections (more than all of the internet connections in the world)
Temporal Lobe Side View of Brain Parietal Lobe Frontal Lobe Occipital Lobe Cerebellum Brain Stem
Brain’s Regional Functions • Cerebellum – Coordination of muscle activity • Occipital lobes – Visual cortex • Parietal lobes – Integration of sensory functions (touch, pain, visual, etc) • Temporal lobes – regulation of emotions and sexuality • Frontal lobes – executive function, judgement, insight, impulse control (40% of brain’s total volume)
The Amazing BrainCreation of God • One neuron can have up to 10,000 synapses. • One neuron can send a thousand electrical impulses every second. • In a fraction of a second, one neuron can simultaneously send a signal to hundreds of thousands of other neurons.
How Neuroscience Has “Opened” the Brain for Study MRI (Magnetic Resonance Imaging) Utilizes magnets instead of x-ray Can therefore be done repetitively on an individual without brain damage fMRI (Functional MRI) Functioning brain tissue utilizes oxygen. Increased blood flow to an area of the brain that has become active can be detected by fMRI. PET (Positron Emission Tomography) . For brain function study FDG (fluorodeoxyglucose), a modified glucose molecule is often used. PET detects active areas of the brain by identifying concentration of isotope in those areas.
Findings from MRI Studies • MRI longitudinal brain studies of proliferation of synapses • the first period of dynamic brain development is in fetal and early childhood life • A second period of dynamic brain development begins just before puberty • This second period of development ends with full maturation of brain development • One of the last portions of the brain to mature is the prefrontal cortex of the frontal lobes • occurs in the mid-twenties
3 months Birth 2 years BIRTH 3 MONTHS OLD 2 YEARS Proliferation of Neurons & Synapses
What happens to all those connections? • A lifelong process called “pruning” which helps the brain to be more efficient. • Neural pruning: Is the process whereby the most frequently used neuronal connections are strengthened and the less frequently used, become degenerate.
Throughout Life Therefore:Use It or Lose It Pruning SOURCES: Dr. Jay Giedd, Chief of Brain Imaging, Child Psychiatric Branch—NIMH; Paul Thompson; Andrew Lee; Kiralee Hayashi; Arthur Toga—UCLA Lab of Neuro Imaging and Nitin Gogtay; Judy Rapoport—NIMH Child Psychiatry Branch. TIME Diagram by J oe Lertola. TIME.com graphic by Garrett Rosso. The Image Bank—Getty Images from the May 10, 2003 issue of TIME MAGAZINE
Adolescent Brain Plasticity MRI studies clearly show that during adolescence, the brain is in a dynamic state and that it exits this period in a different state from which it enters. During this period brain functions are sculpted to allow increasing maturity in thought and action.
The Brain is Involved in all Growth and Development • physical • mental • cognitive
Physical Maturity • Usually complete during teen years • At age 18 LeBron James could play basketball Better than most other basketball players in The world.
Mental Maturity • Complete during teen years • Many adolescents are quite intelligent; some are extremelyintelligent • Mozart wrote his first symphony at age 8
Cognitive Maturity • Centered in the frontal lobes of the brain • Activity of frontal lobes is often referred to as “Executive Function” • Scientists have discovered that cognitive maturity isn’t complete until about age 25 • Just because cognitive maturity isn’t complete until about age 25, doesn’t mean that young people can’t make some good decisions. • This information is an explanation…never an excuse!
Cognitive Maturity If I only had a frontal lobe… • Seeing how “What I do today affects my future.” • Associating cause & effect • Rational behavior & decision making • Emotional stability & self-esteem • Social & communication skills
Cognitive Maturity (continued) • Judgment • Moral intelligence • Abstract thinking • Seeing what is not obvious • Planning for the future • Understanding rules of social conduct • Impulse control .
Myelination • Fatty covering of axons– glial cells myelinate neurons • Improves signal transmission efficiency 100 x • not completed in pre-frontal lobes mid-20s • Grey matter myelination into white matter; continues into 40s
Myelination (continued) • Grey matter of immature brains allows only slower transmission and recovery times • Myelination occurs from the back of the brain to the front over time • Scientists estimate myelination increase in transmission time and decreased recovery time is equivalent to a 3,000 fold increase in bandwidth.
Brain Development – Age 5 Images courtesy of Jay Giedd, MD, National Inst of Mental Health
Brain Development – Age 8 Images courtesy of Jay Giedd, MD, National Inst of Mental Health
Brain Development – Age 12 Images courtesy of Jay Giedd, MD, National Inst of Mental Health
Brain Development – Age 16 Images courtesy of Jay Giedd, MD, National Inst of Mental Health
Brain Development – Age 20 Images courtesy of Jay Giedd, MD, National Inst of Mental Health
Adolescents May Make Bad Decisions, Even to Age 25 • Really? Did you? • Young drivers wreck too many cars • Because of this, car most rental companies won’t rent to persons under the age of 21 and for drivers ages 21 to 25 they charge and extra $25 - $30 per day!
High School Students & Risky Behaviors • 39.2% texted or emailed while driving a car in the past month (of the 64.2% who drive) • 29.8% drank alcohol in the past month and 13.5% had at least 5 drinks in a row. • 35.6% have tried marijuana at least once • 19.5% smoked cigarettes or cigars or used smokeless tobacco or an electronic vapor product in the last month. CDC. 2017. YRBS.
Excitation – Vital Function of Brains • The transmission through the neuron and across the synapse is an “excitatory” process. • All learning is dependent on “excitation” • Excitatory axons and neurotransmitters (like glutamate) dominate in adolescents. This helps explain why young people learn so easily. • The hippocampus contains the highest density of excitatory synapses in the brain and is the brain’s center of memory processing and learning.
Excitatory vs Inhibitory Synapses & Neurotransmitters • There are also inhibitory axons and neurotransmitters such as GABA (gamma amino butyric acid) • Excitatory function dominates in adolescence, which is one reason they can be: • Risk takers • Emotional • Stressed • But also why they learn so easily • As the frontal lobes mature, they gradually bring balance to one’s brain
The Amygdala • The amygdala processes emotional information, especially danger and threat, fear and stress. • This can result in a young person overreacting to fear or stress. • As frontal lobes mature, they balance the amygdala, enabling a more rational and reasonable response to threat or what may be perceived as threat and/or stress, etc.
Teen Stress & Other Neurohormones • THP • Tetrahydropregnanolone • Calms adults but stirs up anxiety in teens • Adrenalin • With stress the amygdala signals the pituitary to have the adrenals release adrenalin – increasing stress • Cortisol • Higher levels in adolescents, increasing stress, worry, anxiety, anger
Danger for the Amygdala – Hippocampus Complex • Hippocampus – Memory • Amygdala – Mediates stress • Excessive stress in teens (or alcohol and cannabis use) • Amygdala appears to grow in size • Hippocampus appears to get smaller (not good for memory and learning) Teens simply do not have the same tolerance for stress as adults
Bright Side of Adolescent Brain Function • Their risk taking has a very beneficial aspect. They are willing to take chances and “explore” the world. • Try out for sports • Take harder classes • Apply for a job • Leave home
Brain Hormones • Constantly bathe our brain tissue • Powerfully impact all aspects of brain function
Neurohormones There are over 100 neurochemicals/ neuropeptides synthesized or stored in the human brain, which includes these neurohormones: • Oxytocin • Vasopressin • Dopamine • Serotonin • Pheromones • Many others
Dopamine • Dopamine is secreted into the brain in response to: • Excitement • Pleasure • New things • Adventure • Risk taking • Addictive drugs • Sex
Dopamine • Dopamine causes a person to feel good by producing intense energy, exhilaration, and focused attention. • Dopamine is involved in the feeling of need or desire to repeat pleasurable acts. Therefore, dopamine presence is termed a “reward signal.” • We are biologically designed to enjoy new things. That is how we find new sources of food and new partners and find out where dangers are
Dopamine – A Necessity for Normal Adolescent Development Dopamine is important for “lighting the fire” in adolescent brains to: • desire to win awards • enjoy learning • be successful in sports • drive a car • etc.
Dopamine and Adolescent Development Dopamine motivates the adolescent to take the risks necessary for the pursuit of independence: • to take the risk of separating from parents into maturity • to take the risk of finding out who one is and where one fits in, including finding an occupation • getting married • the release of and response to dopamine is exaggerated in the teen brain
Dopamine and “Addiction” • Then there’s the addictive quality. For men and women alike, dopamine – the chemical that injects intense pleasure in activities as diverse as gambling and drug addictions rockets during sexual encounters. • Addiction is defined by Dorland as “ the state of being given up to some habit, especially strong dependence on a drug”
“Good old dopamine, the chemical mover that gets us to chase after whatever it is we want, whatever spells relief. For starving animals, dopamine makes the brain a vehicle for seeking food; for addicts, it send the brain hunting for drugs. In fact, dopamine-powered desperation can change the brain forever, because its message of intense wanting narrows the field of synaptic change, focusing it like a powerful microscope on one particular reward. Whether in the service of food or heroin, love or gambling, dopamine forms a rut, a line of footprints in the neural flesh. And those footprints harden and become indelible, beating an intractable path to a highly specialized – and limited – pot of gold.” Marc Lewis, Memoirs of an Addicted Brain; A Neuroscientist Examines His Former Life on Drugs. Public Affairs, New York. 2011 pg 156.
The “Dopamine High” • We as a society are doing a remarkably poor job at addressing our adolescents partly hardwired needs for risk, novelty, excitement and peer affiliation • We adults can help provide that as we encourage achievement in academics, sports, spiritual growth, adventures and relationship building • We can encourage the older young person to experience the thrill of gradually becoming independent and self – sufficient.
Dopamine – The Good and the Bad Dopamine can be a reward signal for the excitement of learning, maturing, new relationships, and the possibility of a bright future. or Dopamine can be a reward signal for the excitement of drugs, sex, violence, and other risky behaviors that threaten the adolescent’s future, including the adult structure of their brains.
Oxytocin and Vasopressin • Vasopressin differs from Oxytocin by two amino acids –still very similar actions • Oxytocin is predominantly involved in maternal behaviors • Vasopressin is more important for defensive and paternal behaviors • Oxytocin has been much more widely studied than vasopressin
Oxytocin • Produced by the paraventricular and supraoptic nuclei of the hypothalamus. • The body uses it both as a hormone circulating in the blood and also as a neurotransmitter in the brain • Peripheral actions • Induces labor • Promotes milk letdown • Released during orgasm in women and in sexual arousal and orgasm in men