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The Use of Technology in Brain Research
RIANE B, DAISHA L , PETA G, ASIA G, XENA N, BRITTNY T
Technology and Neuropsychology
Modern technology is now extensively used in neuropsychology Provides an opportunity to study the active brain Allows researchers to see where specific brain
processes take place Enables the study of localization of functions in the
brainExperiments with animals is still widely used
Allows the study of specific biology that correlates to behavior using invasive techniques: removing(ablation) or scarring(lesioning) brain tissue in order to study behavioral changes
Rats and Psychology
Hetherington and Ranson (1942) lesioned the ventromedial hypothalamus in rats Rats increased their food intake dramatically, almost
doubling their weight. Led researchers to believe the hypothalamus acted as
a brake on eating The full purpose of the hypothalamus is still not yet
understood.Is it ethical?
Ethical concerns arise with using animals with cases that involve lesioning and ablation, potential irreversible harm
Brain Scanners
EEG(electroencephalogram) When neurons transport information an electrical change occurs
EEG picks up voltage change but cannot reveal what is going on the deeper regions
Provide a better understanding of behaviors of the brain: sleep, emotions, epilepsy
PET(positron emission topography Scan monitors glucose metabolism in the brain Patient injected with radioactive glucose and the radioactive particles
emitted are detected by the PET scanner Scans produce colored maps of brain activity Has been used to diagnose abnormalities, to compare brain differences
between normal people and ones with psychological disorders and to compare sex differentiation
Greatest advantage: It can record ongoing activity in the brain
Brain Scanners: Continued
fMRI Provides 3D pictures of the brain structure using
magnetic fields and radio waves. Shows actual brain activity Higher resolution than PET scans and is easier to
carry out. Most frequently used in research today
Evaluating Brain Scanning Techniques
Although you can learn a lot through brain scanning there are limitations The MRI scanner is not good for cognition(There’s a
question of ecological validity) The colors of the different activities of the brain could
be exaggerated Areas of the brain activate for many reasons (just
because it does not light up does not mean its not working)
TOK Ethics
PET-fMRI scans help psychologists to identify brain patters for dysfunctional behaviors. Similar to fingerprints(scanning images)
Specific patters exists for individuals with schizophrenia, alcoholism, depression and other disorders
Even if a person does not show symptoms of disorder, patterns are still present.
J ESSIE HUGHESSA RA H K ERM A N
SA N A K HAT RIDA NIELLE LA F LUER
C J J A S INSK I BRIA NNA J ONES
CRIST INA DERESPINES
Brain Plasticity
Brain Plasticity
Prior to 1960, it was thought that the brain could only be influenced by genetics.
In 1965, researchers Hubel and Wiesel introduced that the environment also influences the brain.
A higher cognitive functioning area of the brain, the cerebral cortex, could be influenced or modified by the environment.
Rats were used as lab experiments.
Dendritic branching is when we learn something new
Brain Plasticity
The changes that occur in the structure of the brain as a result of learning or experience are called brain plasticity.
Plasticity can change functional qualities of various brain structures.
High levels of stimulation lead to an increase in density of neural connections
The brain of a musician should have a thicker area of the cortex related to mastery of music.
Studies of brain plasticity were conducted by Rosenweig and Bennet in 1972.
Placed rats into on of two environments with the goal of measuring the impact of enrichment or deprivation on development of neurons in the cerebral cortex. Enriched environment involved stimulation play toys Deprived environment involved no toys.
Post-mortem studies showed those rats in the stimulation environment had increased thickness in the cortex.
The rates also have a heavier frontal lobe which is linked to greater decision making, thinking and planning.
Interaction with other rats further increased the cortex thickness.
Mozart Effect
One of the most well-known claims of brain plasticity is the Mozart Effect.
Listening to the music of Mozart with temporarily increase spatial reasoning ability.
Exposure to musical compositions that are structurally complex excites the brain the same as when physically completing tasks.
The brain develops a more sophisticated ability to solve spatial problems.
Experiments on brain plasticity cannot be done in humans due to our genetic makeup and environmental inputs differ.
Learning results in an increased of dendrite branching.
RACHELLE BLASH, MADISON CARR, ADINA BESLAGIC, GLORIA MENSAH, EBONY
HARGRO, RASHAAN WILLIAMS
The Effect of Cognition on Physiology
The Experiment
Conducted in 2004 by Richard Davidson
Involved 8 Buddhist monks who were highly experienced in meditation and 10 volunteers who had been trained in meditation for a week
Both groups were told to focus on love and compassion while meditating
Experimenting
Using a PET scan, it was concluded that two of the volunteers and all of the monks had an increase in the number of gamma waves in their brain during meditation Gamma waves are linked to higher reasoning faculties
When volunteers stopped meditating their number of gamma waves returned to normal
The monks’ number of gamma waves did not decrease; they remained at a high level
Monks train for more than 10,000 hours to become adept at meditation
Findings
The area in the brain creating gamma waves was found to be bigger in the monks rather than the volunteers
Davidson concluded that meditation could have significant long term effects on the brain and how it processes emotions
Indicates that the brain adapts to stimulation from either the environment or our own thinking
Mirror Neurons“Mirror neurons on the wall, reflect behavior of them all.”
BAILEY, ALEX, CHASE, TREA, JUSTIN
What are mirror neurons?
Fires when an animal/ person performs an action or when the animal observes somebody else perform an action.
“Mirrors” the behaviors of others.
How was it discovered?
Discovered by accident in 1996, at the university Parma in Italy, as they carried out an experiment with motor neurons.
They found that neural messages send electrical signals in nature. The scientists were able to hear the crackle of the electrical signals when a motor neuron was activated.
The Monkey and Peanut
Whenever a monkey reached for the peanut, the crackling noise was heard.
When the scientists tried to reach for the peanut, they heard the noise of the electrical signal from the electrodes in the monkey’s brain.
Humans
In 2004, Marco Lacoboni asked participants to look at faces while undergoing an FMRI. The same signals which were activated in the monkeys were activated in the humans.
The limbic system was stimulated.A happy face= pleasure!
Understanding Mirror Neurons
Mirror neurons help us understand why we immediately/ instinctively understand people’s thoughts, feelings, and intentions (empathy)
This plays a role in how people react to sports, theatre, and video games.
Example
http://www.youtube.com/watch?v=1tBkPxrQ9dQ
WYATT ANDRESENEUGENE KYEREELIJAH DAVILATRÉ SAUNDERS
The Endocrine System
Hormone Chart
Hormone Gland Function
Adrenaline Adrenals Fight or Flight, Arousal
Cortisol Adrenals Arousal, Stress hormone, Memory
Melatonin Pineal Regulation of Sleep
Oxytocin Pituitary and Hypothalamus
Mother-Child Attraction
Testosterone and Estrogen
Gonads Development, Emotion
Hormones
Enter directly into the bloodstream Take longer to produce changes than
neurotransmitters Chemicals serve as hormones and neurochemicals
Oxytocin
Plays a role in inducing labor contractions and lactation
Released when hugs are givenInduces bonding between mother and child, as
well as between loversAppears to change the brain signals related to
social recognition via facial expression This may be done by changing the firing
neurons of the amygdala The amygdala has an important role in processing
emotional stimuli
Oxytocin Continued
It is known as the ‘love hormone’It is an effective mediator of human social
behaviorOxytocin given to healthy individual seems to
effect circuits involved in fear regulation Trust increases in general
Research is being done to see if Oxytocin helps people suffering from social anxiety
Melatonin
It is produced by the Pineal glandIt is stimulated by darkness and inhibited by
lightMelatonin levels peak near midnight and
gradually decrease towards morningAs days get shorter during winter there is
more darkness, meaning that you are more tired
Artificial lighting has certainly affect ‘awake time’ dramatically
Melatonin Continued
Melatonin correlates with the Circadian Rhythm Circadian Rhythm – any biological process that
oscillates over about twenty four hoursTaking a melatonin pill in the early evening can
help with sleepThere is evidence that higher levels of melatonin
contribute to Seasonal Affective Disorder (SAD) SAD is a subcategory of depression characterized
by sleepiness, lethargy, and a graving for carbsReduced levels in autumn and winter are believed
to mess up the Circadian Rhythm in certain people