The Effect of Cognition on Physiology

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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
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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 brain
 Experiments 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
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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
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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
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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.
Brain Plasticity
JESSIE HUGHES
SARAH KERMAN
SANA KHATRI
DANIELLE LAFLUER
CJ JASINSKI
BRIANNA JONES
CRISTINA DERESPINES
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.
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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
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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.
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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.
The Effect of Cognition on
Physiology
RACHELLE BLASH, MADISON CARR, ADINA
BESLAGIC, GLORIA MENSAH, EBONY
HARGRO, RASHAAN WILLIAMS
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
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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
The Endocrine System
WYATT ANDRESEN
EUGENE KYERE
ELIJAH DAVILA
TRÉ SAUNDERS
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 given
 Induces bonding between mother and child, as well as
between lovers
 Appears to change the brain signals related to social
recognition via facial expression
 This may be done by changing the firing neurons of the
amygdala
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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 behavior
 Oxytocin given to healthy individual seems to effect
circuits involved in fear regulation
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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 gland
 It is stimulated by darkness and inhibited by light
 Melatonin levels peak near midnight and gradually
decrease towards morning
 As 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 hours
 Taking a melatonin pill in the early evening can help with
sleep
 There 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 carbs
 Reduced levels in autumn and winter are believed to mess
up the Circadian Rhythm in certain people
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