Localization of function

Localization of function

The theory that certain areas of the brain are responsible for certain psychological functions.

Strict localization

The idea that there is a clear correspondence between psychological functions and brain areas, and that all functions can be clearly mapped onto the brain.

Weak localization

The idea that one brain area may be responsible for a function, but not exclusively, and other areas may also take over the function.

Widely distributed functions

Functions that cannot be localized anywhere in the brain.

Frontal lobe

Responsible for reasoning, planning, thinking, decision making, and voluntary actions.

Parietal lobe

Involved in movement, perception, and recognition.

Temporal lobe

Processes auditory information, memory, and speech.

Occipital lobe

Responsible for visual processing.

Broca's Aphasia- case study

• Patient: Louis Leborgne ("Tan")

• Lost ability to speak & write at age 30

• Could understand speech but could only say "tan"

• Retained intelligence & speech comprehension

• After death, autopsy showed lesion in left hemisphere (posterior inferior frontal gyrus)

London Taxi Drivers Study (Maguire et al., 2000)- Aim

To investigate differences in brain structure, specifically the hippocampus, in London taxi drivers compared to non-taxi drivers.

London Taxi Drivers Study - Participants

• 16 right-handed male taxi drivers (avg. 14.3 years experience)

• Control group: 50 healthy right-handed non-taxi driver males

London Taxi Drivers Study - Method

• Quasi-experimental design

• Compared 2 pre-existing groups (taxi vs non-taxi)

• Correlational (grey matter volume & experience)

• MRI to measure brain structure

London Taxi Drivers Study - Procedure

• Compared MRI scans of taxi drivers vs controls

• Correlated taxi driving experience years with MRI results

• Measured grey matter volume in hippocampus

London Taxi Drivers Study - Results

• Taxi drivers had increased grey matter in posterior hippocampus

• Controls had more grey matter in anterior hippocampus

• Positive correlation between experience & posterior hippocampus size

• Grey matter redistributed from anterior to posterior in taxi drivers

London Taxi Drivers Study - Conclusion

Grey matter redistributes in the hippocampus after intensive navigation experience. Posterior hippocampus role is recalling learned spatial info, anterior is learning new spatial info.

Posterior

Recall (learned spatial info.

Anterior

Learning new spatial info.