NOTES. Brain and Neural Anatomy and Physiology Review. Developed by Fabio Comana, MA., MS., All rights Reserved Page 1

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1 Brain Fitness - Discovering the Missing Link between the Mind and Body Fabio Comana, MA., MS., NASM CPT, CES & PES; ACE CPT & LWMC; ACSM HFS, NSCA CSCS; CISSN National Academy of Sports Medicine fabio.comana@nasm.org 3 4 lbs. (cupped hands), yet consumes 20% of resting metabolism of the body ( kcal per day) Composed of: o 78 % water, 10 % fat, 8 % protein and 4 % various compounds and elements Contains 100 billion neurons or nerve cells Brain Evolution: Endurance Running and the Evolution of Homo Lieberman, D & Bramble, D. Survival muscle fiber differential = bipedal species: o Longer limbs, shorter toes, less hair, thermoregulation, inner-ear balance (movement shaped body). o Brain size increase 3x larger relative to body size v. other mammals. Need for social interaction planning/thinking complicated patterns group hunt Increased capacity for activity stimulated brain growth. Animal studies endurance training = BDNF. Aging and Brain Decline: Decreases mental efficiency and memory decline = #1 cognitive complaint in older adults: o After age 20 = 1% loss of hippocampus mass/year (memory and learning). o 10 % of adults > age 65 have some form of cognitive impairment. o 50 % of adults > age 80 have some form of cognitive impairment. Generally attributed to: Physiological losses within cells, tissues, organs and systems. Disease (Alzheimer s, cardiovascular disease). Lack of use (repetition or practice), lack of physical activity. Depression and medications. Research: 37 cognitively healthy, sedentary adults (57 75 years old). 60-min aerobic exercise; 3x/week 12 weeks. Measurements: Cognition, resting cerebral blood flow (CBF), aerobic fitness. Results: Increased regional CBF anterior cingulate and hippocampus (cognition and memory). Other Research: Mental training exercises = increased whole brain blood flow. Conclusion: Combo physical & mental exercise = best cognitive solution Brain and Neural Anatomy and Physiology Review Developed by Fabio Comana, MA., MS., All rights Reserved Page 1

2 Regions: Cerebrum and Cerebellum Frontal lobe: Cognition. Controlled processing and responses (cognitive and emotional), conscious thinking and decision-making, concentration, planning, judgment, analysis and inhibition (paralysis by analysis). Motor cortex (middle-top section) coordinates voluntary movements (arms, legs, facial expressions) Parietal lobe: Integrates feelings and sensations (kinesthetic, pain, taste) Temporal lobe: Language (speech) and hearing, information retrieval. Right side = visual cues and left side = verbal cues Occipital lobe: Visual image perception and recognition (shapes and colors) Cerebellum: Motor patterns, balance and equilibrium, coordination, posture, contains 50 % of brain s neurons Delivery Ability to Recall After 3 hours After 3 days Spoken Explanation 25 % % Written Instructions 72 % 10 % Demonstration (verbal and visual) 80 % 65 % Personal Experience / Practical Activity 90 % 70 % Learning Mode Recollection Read 10 % Hear 20 % See (still pictures) 30 % (recall improves with video sequences) Hear and See 50 % (watching a demonstration) Say or Discuss with Others 70 % Personally Experience (i.e., do) 80 % Teach % Regions: Limbic System Human emotion (sex, rage, fear, emotions) Cingulate Worry center of the brain Gyrus: Hippocampus: Learning first stored here (converts short-term to long-term memory), most affected by exercise and brain exercises Amygdala: Emotional reactions - can cut off signals to frontal cortex (i.e., rational processing) always try decrease emotional responses. Very involved with learning (converting short-term to long-term memory) can improve learning when there is an emotional connection. Assigns intensity of worry (stress perception) activates the adrenal gland (discussed later) Nucleus accumbens: Motivation, pleasure (addiction) - brain's pleasure center, as this cluster of neurons modulates effects of dopamine. Developed by Fabio Comana, MA., MS., All rights Reserved Page 2

3 Corpus Collusum: Connects left hemisphere (language) with right (visual, spatial) hemisphere Brain Stem: Also known as mid- or hindbrain and comprised of : Thalamus - processing incoming information and then controlling emotional responses Hypothalamus body s thermostat (autonomic nervous system), eating, drinking, core temperature. Pons breathing (respiratory center) and sleeping Medulla oblongata - controls and regulates involuntary movements (heartbeat, breathing, blood pressure, digestion, regurgitation - vomiting, swallowing, urination, defecation and any lifesaving reflexes). Basal Ganglia: Sub-cortical gray matter nuclei acting as processing link between thalamus and motor cortex for initiation/direction of voluntary movement, balance (inhibitory), postural reflexes, regulation of automatic movement. Nerves (Neurons) Facts of Interest: Myelin Sheath: Develops within first few years of life (crawling to walking) accelerates nerve impulse speed (6 33 feet / sec v. 330 feet /sec). Nerve junction (nerve-to-nerve) = Synapse which occurs within 1/1,000 th of a second Neurotransmitters (NT) bridge synapse connecting neurons: o 80 % of brain signalling carried out by 2 NT (workhorses): 1. Glutamate stimulates activity 2. GABA (gamma-aminobutyric acid) inhibits activity o Regulator: Serotonin affects moods (relaxation), anger, impulsivity and aggressiveness. Serotonin re-uptake inhibitors (Prozac) help reduce anxiety o Regulator: Norepinephrine (NE) affects attention, motivation and arousal o Regulator: Dopamine affects rewards (satisfaction), pleasure and focus (e.g., Ritalin) Post-synaptic receptors can up-and down-regulate in sensitivity and in number. o Example: increased number develop with addictions; suffer withdrawals when not satisifed. o Treatment involves helping reduce receptor number Brain Fitness Brain Plasticity (research from past years): Capacity of the brain to modify its structure and function due to an altered interaction within the environment. Requires principle of overload to trigger adaptation Developed by Fabio Comana, MA., MS., All rights Reserved Page 3

4 Three key traits to healthy brain function: 1. Education (learning) remodels brain (plasticity) 2. Exercise (physiological changes) 3. Self-efficacy (affects cerebrum and limbic systems) Exercise Changes and Benefits: Exercise increases Brain-derived Neurotropic Factor (BDNF) o BDNF strengthens and cleans synapses. o BDNF increases synaptic efficiency, increases synaptic connectivity (mapping), increases the number of new circuits to offset lost circuits. o BDNF grows neurons and dendrites. Exercise increases Vascular Endothelial Growth Factor (VEGF) that builds capillaries within the brain. Exercise increases Fibroblast Growth Factor-2 (FGF-2) that stimulates tissue growth via longterm potentiation (LTP). o LTP = increased synapse efficiency and affinity between neurons to facilitate learning and retention. Exercise helps push Insulin-like Growth Factor-1 (IGF-1), manufactured within muscles into brain one role is to increase glucose uptake into cells (fuel). o IGF-1 complements actions of BDNF Exercise strengthens the Corpus Collusum connects two hemispheres Exercise balances/increases levels of NT o Increases in glutamate, serotonin, and even dopamine - also balances NT levels in brain Exercise strengthens the Corpus Collusum connects two hemispheres Blood Brain Barrier (BBB), a web of capillaries tightly packed to filter compounds improves efficiency of passage into brain. Exercise induces stress: o Amygdala perceives stress and activates adrenal glands Exercises (mental and physical) Goal: Maintain ability to transition working memory into long-term memory (IQ) Backward Digit Span: o Counting numbers backwards in intervals (e.g., 7 s from 100) Word Spell: o Spell words backwards, progressively increasing length of the word o Example: World Hospital Responsibility Sequenced Information Games: o Choose sequence of names. Fred, Stacy, Richard, Stanley, Ida, Edward. o Read, then recite forward o Recite backwards o Arrange alphabetically o Arrange by word length N-back Test: o Deck of cards select trigger card (e.g., Queens), flip through to trigger, then remember card before it, 2 before, etc. Physical: Cardio and Resistance Training 8 12 minutes per day of exercise evoking sweat and labored-breathing (> 60% of MHR) 30 min cardio, 2 3x/week, for 12 weeks = increases BDNF, but faster with cross-lateral patterns (XLP). o XLP also strenghtens the Corpus Collusum effectively o XLP also increases the number of post-secondary dendrites Low-to-moderate cardio exercise: Developed by Fabio Comana, MA., MS., All rights Reserved Page 4

5 Physical: Cardio and Resistance Training 8 12 minutes per day of exercise evoking sweat and labored-breathing (> 60% of MHR) 30 min cardio, 2 3x/week, for 12 weeks = increases BDNF, but faster with cross-lateral patterns (XLP). o XLP also strenghtens the Corpus Collusum effectively o XLP also increases the number of post-secondary dendrites Low-to-moderate cardio exercise: o Increases BDNF, little increase in IGF-1 Moderate-to-vigorous exercises (> 65 % of VO 2 max): o Increases BDNF, VEGF, FGF-2, IGF-1, and HGH Resistance training (2x/week) increases VEGF, FGF-2, IGF-1 and HGH (with more vigorous training). BDNF: o Daily exercise is better than on alternate days (150 % increase v. 124 % increase), but about equal after 4 weeks. o After 2 weeks of detraining BDNF returns to baseline, but re-starting exercise equals 137 % increase with daily v. 129 % with alternating days after 2 training sessions. Stress: Cortisol Impairs cells in the hippocampus involved with short-term memory, learning and memory. Can ultimately = hippocampus damage becomes smaller due to free radical attacks (reduces long-term memory), destroys and shortens dendrites, decreases levels of BDNF, reduces neurogenesis, and increases neural atrophy Amygdala (emotions) will control hippocampus = increased emotional stress vicious cycle. Cortisol also impedes transition to stage 4 sleep (delta or deep sleep) where short-term memory is converted to long-term memory. Dietary Ideas: Anti-oxidants (fight free radicals) may prove effective (e.g., berries, pomegranate, spinach, green tea, etc.). Fish oils (Framingham Heart Study) 3 fish meals per week. o Used 1,200 mg (EPA (eicosapentaenoic acid) and 200 mg of DHA (docosahexaenoic acid). o Slows yearly rate of cognitive decline by 10 %. o Associated with a 50 % decline in risk of developing dementia. Folate (800 mg) improves memory and processing speed (e.g., beans, spinach, cabbage, broccoli, asparagus) Healthy sources of glucose fuel. o BUT. glucose = insulin = uptake of all nutrients (amino acids) into cells o Muscles don t care for tryptophan increased levels = serotonin. o BCAAs in blood may help reduce fatigue-inducing effect of tryptophan Pycho-emotional Impact: Popular programs experience self-efficacy? Willpower: Research: Landmark Willpower study (Baumeister, et al, 1996). 67 college students; Stimulus: Chocolates + confections sight/smell. Indulge v. eating radishes only, followed by tackling puzzles (20-min v. 8-min effort). Discoveries: Body uses same energy for self-control as for decision-making. o Acts of self-control reduce blood glucose levels o Low glucose levels = poor performance on self-control tasks/tests. o After decision-making self-control lowers o After self-control, brain favors simpler and easier decisions or no choices. Developed by Fabio Comana, MA., MS., All rights Reserved Page 5

6 Step One: Self-control Exercises Human spends 3 4 hours resisting desires willpower depletes throughout day (easier to gain victories in am). o Aim for early victories in morning (e.g., breakfast snack) spillover effect. Self-control training (few weeks): o Practice overriding habitual ways of doing things exerting deliberate control over actions: o Generic left hand v. right hand tasks o Specific manage money to save. Step Two: A Systematic Approach: Developed by Fabio Comana, MA., MS., All rights Reserved Page 6