can exercise change your brain 253 lecture 16

childhood and adolescence

Increasing evidence PA can have a significant impact on congnitve function of children and adolescents Promising relationship between physical fitness and academic acheivement - higher aerobic fitness predicted better performance on achienvement -greater body fat predicted worse performance higher fit children more accurate response rate task perforamce after acute exercise are more accurate indicated greater alocation of attetnional resources measuring weight body mass index 1 rep max kids who are fit higher academic achievemtn issue higher physical activity SES and education congnitive reaction time, different obese kids vs fit kids being overweight brain processing fucntion different , how fast a car coming, hormone in brain

observation cohort studies

Many are prospective cohorts- examined at one point in time then re-examined later Older individuals who engaged in exercise at least 3 times a week at baseline were 34% likely to develop Alzheimer 6 years later Aerobic fitness positively associated with later cognitive function -Aerobic fitness may buffer against development of cognitive impairment Overall Even models levels of PA seem to have positive influence on cognitive function Reduce risk of Alzheimer significantly

Hippocampus

Memory also weakens with ageing - hippocampus is important for memory and atrophies (declines) with age Levels of aerobic fitness associated with hippocampal volume -greater fitness and hippocampal volume associated with better spatial memory performance -one year aerobic exercise intervention increased hippocampal size, essentially reversing atrophy by one to two years -increased hippocampal volum was also accompanied by improvments in memory function Hippocampus related to memory, Erikson level of exercise assoicated with hippocampal volume he looks at longutuide stidues, people over time so control nutrition, stress 1 year of exercise reversed brain in what happen in 2 years

Intervention studies:Effects on cognitive function

Meta-anyalsis for exercise training studies Strongest effects seen for cognitive task involving executive control processes -exerciser had nearly 30% greater effect than control comparison Training programs that included both aerobic, strength and flexibility training superior to aerobic exercise only -effects greatest when exercise exceeded 30 min strongest effects, executive control, memory processing speed clinically significant : people know it makes a different they say they can recognize improvements self efficacy increases exerciser does response: 30 minutes optimal impact exercise, 6 minutes still increase brain function learning

Video

Video: Medical treatment improve memory, at risk for alzhemiers, mild memory complaining old people. Study demostrated, individuals were separeted 142 exercise each week. control group who didnt excercise brain performance decreased alxhemiers assement skills showed improvment when they did excercise. Exercise mostly improved cogniztion in memeory. First study intervention can improve memory by aerobic excercise. Aerobic exercise turns on genes that allows your brain to grow new memory cells. Actual change was small when excercise but whithout execerise big decrease in cognitive ability. Both had same baseline. 18 months people in control said memory worse and people excercise at 18 months said memory got better.

Reveiw children

2016 acadamic achievemnt Spark:Single based activty can give children brief short exercise and will improve cognitive function

Defining cognitive function

Ability to perceive, recognize or understand thoughts and ideas - concentrate or divide ones attention -learn and remember -make and execute plan of action -self regulate activities -recognize objects or things -evaluate -construct thoughts in ones mind -think logically and solve problems In exercise research is how we study in these domains - it complex brain complex organ

Acute exercise studies

Acute exercise has positive, albeit small , effect on cognitive function -exercise more favorable for moderate intesity exercise - May be a debalitating effect of increased exercise intensisty (lactate levels) on congnitive processing single bouts of activity have untility in short term enhancing processing of informaiton when accumualted over weeks and months have profound impact on cognitive processing HITT training can reverse by lactate in brain short term exercise with memeory strip colour word test to look at the effects.

Key growth factos

Brain derived Neurotrophic factor BDNF -Essential for hippocampal function, synaptic plasticity and learning -exercise increases BDNF key finding in many animal studies Insulin like growth factor IGF-1 - Regulated exercise dependent anigensis and neurgonesis in hippocampus -increases oxygen supply and nutrients to nerves in brain limitation: study one rat and not really cant see physical change in brain kinda

Studies on the effect of chronic exercise on cognitive function

Cross section studies -compare exercisers to sedentary, examine fitness across lifespan -cannot tease out other factors (diet, education) groups of people at once, cant get cause and effect, cheap don't take long to do association data, link and relation in data Longitudinal studies -exercise as an intervention give them something and see if changes Alzheimer study exercise example Cohort studies: show strong relationship exercise levels and cognitive ability and Alzheimer; group of individuals measuring them later in life

Intervention studies Effects on brain structure and operation

Decline in cognitive function age related loss of both grey and white matter -anterior brain regions, frontal pre frontal and temporal regions Tissue declines reduced in proportion to individual fitness = sparing effect -follow up study found increase in brain volume after aerobic training -aerobic fitness can preserve brain structure or reverse decline -resistance exercise may have similar benefits Most of this done on rats decline in grey/matter Colcombe:Sparring effect the more you exercise the reduce decline on tissue Resistance exercie work but bulk of study aeroibc reversal effect:change what hapen chronic deseace can reverse some function -

Intervention studies effects on cognitive function

Exercise intervention Physically unfit older adults who participants in programs of regular exercise can improve both fitness and cognitive function -clear significant influence of aerobic fitness training on cognitive functioning look at older population, physical fit Neuroplacticity: change in brain most studies are aerobic fitness training

Mechanisms

Exercise may increase number of synapses in grey matter -important given frontal lobe connection with executive function Exercise may cause increased blood supply to brain regions supporting executive control function - all these changes (neurogenesis, aniogenasis increased blood supply) provide structural and metabolic resources necessary for successful cognitive function growth factors delivered by blood supple

Mecanism to expalin exercise effects

Exercise may induce increases in several kinds of growth factors important for neuronal and brain health Growth factors - neurogenesis new neurones -neurplasticity new connections between neurone -synaptic plasticity connection between neurone to change in strength similar to depression and anxiety brain divide neurotrophic factor and insiline like growth factor

Measures of Executive control

Exercise seems to exert greatest influence on executive control several methods to measure executive control -eriksen flanker test -task switching , reaction time -stroop color and word test These are all behavioural tasks. examine reaction time and accuracy

Executive control

Process controlling cognitive function oriented toward goal directed behaviour or EXECUTIVE CONTROL FUNCTIONS -planning/ scheduling -working memory ability to hold information in mind for short periods of time -inference control ability to deal with distraction -task coordination -multitasking initiation and monitoring actions Pr-frontal cortex, executive control function ,we see changes in that part of the brain when exercise happens HIPPOCAMPUS: impact of exercise reside in prefrontal cortex

Studies of older adults

With advancing age, brain changes in structure and function -gray matter (neurons) and white matter (connections) decrease -brain ventricles increase in size Atrophy associated with decreased cognitive function -decreased performance on neuropsychological test FUNCTION HAS CHANGES BECAUSE STRUCTURE CHANGED

Cognitive function and exercise

determine whether regular PA can prevent decline cognitive function -advancing age determine whether PA can reverse cognitive decline that has already occurred -Alzheimer dementia Examining exercise effect on learning and cognition in children and adolescents prevention:exercise effects on learning/cognitive in children and adults

Cognitive function and exercise

link between exercise and brains ability to process information -connection between mind and body In class sit SPARK PROGRAM: sit up and down boom active kids are likely to improve 20% in learning