BA- brain and behavior Flashcards
theory of localization of function
-specific parts of the brain are responsible for specific behaviors or cognitive processes
-if there is damage to a specific brain area there will be corresponding damage deficit in the cognitive or behavioral processes that that part of the brain is responsible for
-one area that is localized is the hippocampus which is located in the mid-temporal area of both hemispheres and is responsible for the transfer of short-term memory into long-term memories and the overall creation of new memories
-other parts that are localized is amygdala, basal ganglia, hypothalamus and each four lobes
description of case study of HM
longitudinal case study of individual who has sever brain damage
-HM hit by cyclist at 7 years old. Sustained serious head injury. Epileptic attacks began at 10 and at 27 had life threatening seizures.
-Neurosurgeon performed experimental surgery and removed tissue from mid temporal area including the hippocampus from both sides of brain
-RESULTS:
-Forgot daily events
-Could recall little of 12 yrs before surgery
-Could not acquire episodic or semantic knowledge
-Remembered childhood
-No change in personality
-Still able to form cognitive map
-Could still acquire procedural knowledge
Suffered primarily from antro-grade amnesia
-His retrograde amnesia reduced
CONCLUDES
Hippocampus is localized
evaluation of case study of HM
STRENGTHS:
-longitudinal study 50 yrs
-method triangulation used
-high ecological validity
-HM was in his natural environment
-ethical considerations met
WEAKNESSES:
-cannot easily be replicated
-do not a have a lot of data on HMs abilities before accident
-meds used to treat accident may have resulted in damage
retrograde amnesia-
anterograde amnesia-
Retrograde amnesia is when you can’t recall memories from your past. Anterograde amnesia is when you can’t form new memories
function of hippocampus
transfer of short term into long term
-creation of new memories
Link of HM to localization of function
-hippocampus plays critical role in converting memories from short to long term
-short term memory not found in hippocampus as HM was able to retain information if he rehearsed it.
-He was able to remember memories long before surgery, indicates mid-temporal area not site of permanent storage
-each type of memory is related to different areas in the brain
description of Maguire et al study
AIM:
-to see whether the brain of London taxi drivers would be different due to their exceptional knowledge of navigating
PROCEDURE:
-quasi experiment, ingle blind study
METHOD:
-16 right handed male London taxi drivers compared to 50 right handed non taxi driving males
-taxi drivers had to complete knowledge test and have licence for 1.5 yrs.
-sample included a range of ages
-data measured from MRI using:
1. VBM= used to measure density of grey matter
2. pixel counting=counting pixel number to calculate area of hippocampus
RESULTS:
-Posterior hippocampus of taxi drivers were larger than control participants
-anterior hippocampus larger in control participants than taxi drivers
-significant redistribution of grey matter from anterior to posterior hippocampus of taxi drivers in response to environmental demands
CONCLUSION:
-plasticity of hippocampus changes in response to environmental demands
evaluation of Maguire et al
STRENGTHS
1. MRIs provide vast amounts of quantitative data, allowing correlation
2. Researcher did not know which brain scan belonged to which participants = avoiding researcher bias
3. Had many controls
4. Scanning does not pose any health issues
WEAKNESSES
1. Quasi experiment is difficult to draw conclusions- may not occur because of the IV
2. All male participants
3. MRI is not natural
Maguire link to localization of function
- Redistribution of grey matter in hippocampus maybe due to different functions in 2 regions
- Posterior=involved in previously learnt spatial memory due to taxi drivers vast navigation experience
- Anterior=responsible for learning new spatial memory
Maguire link to neuroplasticity
-volume of posterior hippocampus expanded because of dependance on spatial memory
-posterior hippocampus stores spatial representation of environment
Localization of function critical thinking
limited research, only people with brain damage
-very few behaviours appear to be strictly localised, supports idea of interaction
-reductionist approach; human behaviour to specific area of brain
-MRI used may not be completely accurate as other areas of the brain may play a role but not show on the scans
what is neuroplasticity?
-the brains ability to rearrange the connections between its neurons
-the changes that occur in structure of the brain as a result of learning or experience
-high levels of stimulation and learning, lead to an increase in density of neural connections
-everytime we learn something new neurons create a new trace in the brain called dendric branching
-connections with other neurons lead to the formation of neuronal networks
-strengthening synapses through repeated use is called long term potentiation
-neuronal pruning is the erasing of number of synapses that are no longer needed making function of neuronal networks more efficient and for the energy needed to maintain them used elsewhere in the brain
description of study of draganski
evaluation of study of draganski
Draganski link to neuroplasticity
