Ways of studying the brain

• While many questions about how the brain functions remain a mystery, psychologists have made impressive discoveries about states of sleep, language disorders, and many other psychological phenomena like how perception works
• These discoveries would have been impossible without the tools that are now available to researchers in this element of sight
• Spatial resolution


  How accurate it can be about the exact position of a brain structure or activity
• Temporal resolution


  How accurate in time it can be about when the brain activity took place
• Post-mortem dissection


  1. Brains are usually treated chemically or fixed to give them a thermo texture so they can be caught precisely

  2. Brains of people who may have had or neutral brains such as people with mental illness, trauma to the brain, or have shown unusual behavior in life are chosen for dissection

  3. Their brain will be compared to what's called a neurotypical brain or a healthy brain

  4. Any physical differences could be linked to the behavioral differences
• The most famous psychological discoveries made by post-mortem was by Paul Braga, who studied the brain of a patient called Tan, who in life could only say "tan"
• When Tan's brain was studied post-mortem, there was significant damage in the area of the brain in the frontal lobe just above the temporal lobe, which is now associated with Broca's or expressive aphasia, a disorder affecting speech production and understanding
• Advantages of post-mortem brain research

  • You can study the brain and its structures in microscopic detail, even studying individual nerve cells
  • This is simply not possible with other techniques
• Disadvantages of post-mortem brain research

  • These studies happen after death, so there is no way of seeing the brain in action
  • Damage revealed in post-mortem may not be the true cause of the observed unusual behavior
• fMRI (functional magnetic resonance imaging)


  Uses large magnets to detect the blood flow in the brain, with the more active parts needing more oxygen and having increased blood supply
• Advantages of fMRI


  • Creates a very detailed spatial image of the brain with a resolution of up to one millimeter
  • Can precisely identify regions of the brain that are highly active
  • The "functional" aspect means you can see how the brain is working and changing over time
• Disadvantages of fMRI


  • While precise in spatial location of activity, it's less good at identifying the exact time of the activity due to a delay between neuron activation and blood flow
  • The machine is very expensive to build and operate, making experiments expensive
  • Participants must be perfectly still, limiting what can be studied
• EEG (electroencephalogram)


  Uses electrodes placed on the scalp to measure the electrical activity of the brain, producing patterns of activation called brainwaves
• Advantages of EEG


  • Non-invasive, non-surgical way to investigate the living brain
  • Used medically for diagnosis of disorders like epilepsy and experimentally to demonstrate the stages of sleep
  • Significantly cheaper than other brain scanning techniques
  • Portable, allowing use outside the lab
  • Fantastic temporal accuracy, measuring electrical activity in milliseconds
• Disadvantages of EEG


  • Lacks spatial accuracy, only able to assume activity from a general region under each sensor
  • Can only detect activity on the cortex, not deep within the brain
  • Takes a long time to carefully place the electrodes and conductive gel
• ERP (event-related potentials)


  Uses similar equipment to EEG, but looks for the brain's response to a particular stimulus by presenting it many times and averaging the data to isolate the response
• Advantages of ERP over EEG

  • Allows researchers to isolate and study individual neurocognitive processes in the brain, rather than just general brain activity
• ERP is commonly used by cognitive neuroscience to study how sensory and cognitive information processing is linked to the physiological activity of the brain, bridging the gap between biological psychologists and cognitive psychologists
• Researchers are using both EEG and fMRI on the same participants to get a deeper understanding of the brain's activity to a stimulus, as the techniques have contrasting strengths and weaknesses
• In 2018, neuroscientists at the University of Washington demonstrated using EEG and transcranial magnetic stimulation to connect the brains of three individuals together via a computer, allowing them to play a game similar to Tetris by sharing information between their brains