How the human brain works

1. How the human brain works Steve Wengel, M.D. UNMC Department of Psychiatry August 18, 2014

2. Goals for this hour • After this presentation, you will be able to: • Understand how we learn about how the human brain works • List major brain areas and their functions • Describe how normal aging affects brain functions • Discuss the beneficial effects of meditation on the human brain

3. Quiz Are there pain receptors in the brain? How many neurons are there in the human brain? How many synapses does a typical neuron have? Do we make new neurons as adults?

4. Basic brain facts • Messages to and from one side of the body are usually handled by the opposite side of the brain.•  The folded, crumpled structure of the cerebrum contains an enormous amount of small and large grooves and bulges, which greatly increases its overall surface area.  Because of its design, the surface area of the cerebral cortex is tripled and if laid flat, would cover an area of about three square feet. •  There are no pain receptors in the brain, so it can feel no pain.

5. Basic brain facts • There are • 100,000 miles of blood vessels in the brain. • 100 BILLION neurons (nerve cells) • Each neuron has between 1000 and 10,000 synapses (connections with other neurons) • As we age, neurons die • For most areas of the brain, we do not seem to make new neurons after birth – but in some areas, we are able to make new neurons

6. Basic brain facts • The human brain is the fattest organ in the body, consisting of at least 60% fat.•  While awake, your brain generates between 10 and 23 watts of power–or enough energy to power a light bulb.•  Humans experience about 70,000 thoughts each day.•  Children who learn two languages before the age of five alter their brain structure to have much denser gray matter as adults.•  As we age, our brains lose mass.

7. How do we learn how the human brain works? Wait for something bad to happen to a normal person, and see what the result of this is Do experiments on other species Do experiments on humans Find a safe technology to study the brain

8. Executive Functioning • Term used to describe complex brain functions like: • Planning ahead • Anticipating consequences • Supplying motivation and drive • Suppressing inappropriate behaviors

9. Normal development of executive function Gradual process Starts around pre-teen years Fully develops only in the 20s (or never!)

10. Meditation, Mindfulness, Relaxation

11. The “Amygdala Hijack” Term used to describe sudden, intense, unconscious emotional response which “takes over” higher brain centers

12. Physiology of stress • Activation of fight or flight mechanism • Overactivity of sympathetic nervous system • Catecholamine release • Dopamine • Epinephrine • Norepinephrine • Cortisol release • Neuropeptide S

13. Consequences of stress • Cortisol release: • Impaired concentration, short-term memory • Hippocampal atrophy • Neuropeptide S • Insomnia • Sense of urgency

14. Beneficial effects ofmeditation Decreased anxiety Better sleep Better problem-solving Increased empathy Better patient care

15. Effects of meditation on the human brain • Increased cortical thickness in • Prefrontal cortex • Increased attention • Enhancement of complex cognitive behaviors • Right anterior insula • Integration of body sensation, emotions • S. Lazar, Ph.D., Massachusetts General Hospital 2006

16. The “Relaxation Response” • Term coined by Herbert Benson, M.D. • Cardiologist at Harvard • Lifelong research on role of stress on health, and positive effects of eliciting relaxation • Basic tenet: stress response and relaxation response are both hard wired, and mutually exclusive

17. Eliciting the Relaxation Response • The following is the generic technique taught at the Benson-Henry Institute: • Pick a focus word, short phrase, or prayer that is firmly rooted in your belief system, such as "one," "peace," "The Lord is my shepherd," "Hail Mary full of grace," or "shalom." • Sit quietly in a comfortable position. • Close your eyes. • Breathe slowly and naturally, and as you do, say your focus word, sound, phrase, or prayer silently to yourself as you exhale.

18. Assume a passive attitude. Don't worry about how well you're doing. When other thoughts come to mind, simply say to yourself, "Oh well," and gently return to your repetition. • Continue for 10 to 20 minutes. • Do not stand immediately. Continue sitting quietly for a minute or so, allowing other thoughts to return. Then open your eyes and sit for another minute before rising. • Practice the technique once or twice daily. Good times to do so are before breakfast and before dinner. • Don’t do the technique within 2 hours after a heavy meal.

19. More information? www. relaxationresponse.org

20. Practical Mindfulness • When you wash the dishes, wash the dishes • “Stop” for 1-3 minutes every hour during the workday to focus on your breathing, bodily sensations, and thoughts and feelings • Once a week, eat a meal in silence, paying attention to all elements of the experience – the taste, texture and temperature of the food; the muscles you use to cut the food and bring it to your mouth; etc.

21. Practical Mindfulness When getting dressed, start with the opposite arm or leg than you usually use Try brushing your teeth with the opposite hand, or at least start on the opposite side of your mouth