Studying The Brain Flashcards
What is post Mortem examination
-Happens after death
-a long history of use of this in psychology e.g broca and the patient tan
-the modern method is to place the brain in a Belgian block and freeze it (this is what they did to HM brain)
-they then make thin slices to photograph each part and the photographs are used to build a 3D model of the brain
What are the advantages of post mortem ?
-gives very detailed anatomical images of the brain
-can see various NTs and receptor sites
-can see the structural abnormalities associated with the disorder
What are the disadvantages of post mortem
-a large number of individual factors impact brain structure such as ; age,drugs ,smoking and lifestyle
-retrospective -cannot follow up with any links found and look at treatment for the brain as the patient is deceased
Scanning techniques fMRI ( functional magnetic resonance imaging)
-Uses a very strong magnetic field ,3 Teslas which is 50,000 times more than the earth gravitational pull
-this field causes all the water molecules in your body to align
-measures changes in the magnetic field due to blood oxygen level,which indicates brain activity
What are the advantages of fMRI
-fMRI is non invasive unlike PET scans which uses radioactive chemicals
-it is objective and reliable
-very food for temporal and spatial mapping of the brain
What are the disadvantages of fMRI
-not a direct measure as blood flow implies brain activity
-does not tell us how each of theses areas of the brain related to a task communicate together
-cost - this is one of the more expensive methods
NHS £361
$2500 USA
£750 to £1000 private UK
Single areas cost an additional £350
What is EEG (electroencephalogram)
-uses electrodes on the scalp to measure brain activity
-used in sleep research and diagnosis of some disorders e.g epilepsy
What are the 4 basic types of EEG patterns
Alpha -asks
Beta-aroused/alert
Theta-nodding off/light sleep
Delta-deep sleep
What time does EEG record in
real time
What are the advantages of EEG
-Provides real time recording of the activity of the brain
-used in clinical settings
-can be used while the person is asleep unlikes fMRI as fMRI machines are noisy and require you to be still
What are the disadvantages of EEG
-not a direct measure
-cannot be used to locate areas of the brain activity as the electrodes detect activity from several areas
-Cannot tell us anything about the deeper parts of the brain e.g thalamus
What are ERP (event related potential )
-Small voltage changes in the brain is triggered by specific events or stimuli
-using a computer you can turn the EEG output into ERP
-the computer is used to cut out the noise from all, the brain electrical activity , to establish a specific response to a target stimulus and the responses are then averaged together
-can detect very quick. Changes in the nerocortex 1/1000 seconds
What are the 2 categories that ERPs can be divided into
Sensory ERPs
Cognitive ERPs
What are sensory ERPs
Sensory ERPs are the waves occurring within the first 100 milliseconds after the presentation of the stimulus as they reflect an initial response to the physical characteristics of the stimulus
What are cognitive ERPs
Cognitive ERPs are the waves generated after the first 100 milliseconds which reflect the manner in which the subject evaluates the stimulus as they demonstrate information processing
