Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
STUDYING THE BRAIN
Transcript of STUDYING THE BRAIN
Dissect (separate into parts for examination) a brain after a person has died.
Electroencephalograms (EEGs) measuring these frequencies and intensities may be recorded over relatively long periods to study brain-wave activity indicative of changing mental states such as a deep sleep or dreaming.
Pros: non-invasive, practical, & inexpensive
Cons: crude measure – doesn’t indicate precise function of neurons involved
Static Imaging Techniques
Techniques to obtain still images revealing the structures of the brain.
Computerized axial tomography (CT or CAT SCAN)
During a tomography (CT or CAT) scan,
a thin X-ray beam rotates around an area of the body, generating a 3-D image of the internal structures.
During magnetic resonance imaging (MRI), a narrow tube moves the patient through a tunnel-like structure. Inside the structure, radio waves pass through a magnetic field around the patient, creating a 3-D image of the internal structures.
Rely on changes that take place within the brain as a result of increased consumption of glucose or oxygen in active areas of the brain.
Methods for studying the brain
Positron emission tomography (PET) scans rely on increased glucose consumption in active brain areas during particular kinds of information processing
Functional magnetic resonance imaging (fMRI), builds on MRI but uses increases in oxygen consumption to construct images of brain activity
Pros: detailed knowledge
Cons: Expensive & Difficult to interpret because of sensibility to disruption.
In order to study the living brain. Micro-electrodes are inserted into the brain of an animal (usually monkey or cat) to obtain single-cell recordings of the activity of a single neuron in the brain.
Compare alteration in Psychological functioning with location of damage by stroke, tumor, head trauma or virus. (13:42, 11:45, 7:38)
Ablation/lesion: investigate function by removing areas of brain or destroying links between areas (aggression, memory, consciousness, psychopathology
Experimental Exposure: influence brain by using environmental distortion or deprivation (perception).
Using correlational research to establish a genetic argument for the origin of human behavior.
A correlation of:
+1.0 means as x increases, y increases.
-1.0 means that x increases, y decreases.
In twin research, we expect to find a higher correlational than when comparing a child to someone outside of the family.
Comparing Monozygotic twins (MZ) with Dizygotic twins (DZ). Since MZ twins have identical DNA, there should be a higher concordance rate
Comparing MZ twins reared together vs. MZ twins reared apart.
Twin studies have produced a great deal of data in support of biological roots of disorders; this has helped psychologists to stress prevention for those who are vulnerable to such disorders. There is a high cross-cultural reliability of concordance levels.
MZ twins are rarely separated at birth and raised in a totally different environment, yet this is really necessary to substantiate claims. MZ twins reared together share many of the same experiences. DZ twins reared together may not share the same experiences due to levels of attractiveness or temperament.
Adoption studies tend to compare the adopted child with the biological mother and the adoptive mother to determine which has the higher concordance rate for a given behavior.
Adoption studies allow researchers to isolate variables. If a biological mother has no contact since birth and still matches for a specific trait - for example, the adopted child’s IQ is better than the adoptive mother and in concordance with the birth mother - this is strong evidence that genes play a significant role in the development of this trait.
Selective placement is a problem. Babies tend to placed with families similar in background to the natural parents.
Adopted children – as well as twins - are not representative of all children.
The act of being given up for adoption may affect the child’s behavior.
Prospective studies identify traits that are considered to be inherited. Those who are considered “genetically vulnerable” are then followed over many years to see if they actually manifest the behavior.
There is an ethical concern in such research that it may cause undue stress and lead to
effects in those who are labeled as vulnerable.
of or relating to illness caused by medical examination or treatment.
Researchers look carefully at the behavior of people who show signs of brain damage while they are alive, they document the behavior as thoroughly as possible, and after the patient dies, they examine the brain for lesions.
Draganski et al (2004)
used MRI to determine changes in brain structure in response to learning a simple juggling routine for three months.
Draganski et al (2006)
used MRI to see if brain structure changed as a result of revising for an examination in medicine.
Maguire et al (2000)
compared MRI scans between London taxi drivers and controls to see if hippocampus played a role in spatial memory.
Freed et al (2001)
used PET scans to study dopamine-producing cells in the brains of Parkinson's disease patients.
Fischer, Aron and Brown (2005)
used fMRI to study brain processes in response to looking at the picture of a loved one.