To study the brain in psychology, we need tools that accurately represent the complex organ and provide data scientists and medical personnel can analyse. These data must reflect the brain activity and functions and show precisely where the activity occurs in the brain.
Explore our app and discover over 50 million learning materials for free.
Lerne mit deinen Freunden und bleibe auf dem richtigen Kurs mit deinen persönlichen Lernstatistiken
Jetzt kostenlos anmeldenTo study the brain in psychology, we need tools that accurately represent the complex organ and provide data scientists and medical personnel can analyse. These data must reflect the brain activity and functions and show precisely where the activity occurs in the brain.
Modern technology has made significant advances in studying the brain in relation to behaviour, allowing more profound, less invasive insights into how the mind works. However, the history of how the brain was studied before this time is still critical and was essential to the discovery of language centres before these new experimental techniques became available. So we will cover both the older ways of studying the brain in psychology and the modern methods of studying the brain.
Fig. 1: There are multiple ways of studying the brain.
There are a variety of methods available for studying the brain in psychology. Before delving into these methods, however, here are some important terms to remember:
Spatial resolution is the degree of accuracy that a technique achieves when examining brain activity. It is the accuracy with which the exact areas of brain structures and activity are identified.
Temporal resolution is the degree of accuracy in determining brain activity over time that the technique provides. It relates to when the activity virtually occurred and how accurately the technique can record this information.
The main ways of studying the brain consist of:
That's not to say these are the only methods of studying the brain. Other techniques exist, such as computerised tomography scans (CT scans) and positron emission tomography scans (PET scans), however, our focus will be on the aforementioned three methods for this explanation.
As we mentioned briefly above, the three main techniques of studying the brain we are going to focus on are post-mortem examinations, functional magnetic resonance imaging (fMRI), electroencephalograms (EEGs) and event-related Potentials (ERPs). Each has its own preferred method of analysing the brain and its components. Let's explore them further.
Post-mortems were the first official technique for examining the brain. It is now usually performed by pathologists who examine the body and brain after death.In a post-mortem, the brain is treated with a chemical fixative to make it resistant to handling and cutting. This way we can analyse the different sections. Usually, autopsies are good for finding damaged areas of the brain and assigning the injured area to a function, depending on how the patient behaved or suffered while alive.
Broca's area, located in the left hemisphere, is a good example of where a post-mortem examination could identify a functional area in the brain after a patient had suffered from speech problems while alive.
Fig. 2: Post-mortem examinations look at the brain after death.
Functional Magnetic Resonance Imaging (fMRI) detects the change of blood flow in the brain using a magnetic field and is one of the modern ways of studying the brain. This technique can also be used on the brain in relation to behaviour. It does this by detecting the change and flow of oxygenated and deoxygenated haemoglobin during neural activity.
Active brain areas consume more blood (they need more oxygen and glucose to perform activities) and fMRI machines can measure this (the BOLD signal, Blood-Oxygenation-Level-Dependent). fMRI scans provide 3D images of the brain, producing a neuroimage of the brain with areas of activity highlighted. It is a great diagnostic tool as a result.
Abnormalities can be detected using fMRI scans, such as showing a damaged area in the brain.
Fig. 3: An fMRI scan shows areas of activity during tasks, such as a memory task.
Electroencephalograms (EEGs) are a type of brain-studying technique where electrodes (up to 34) are placed on the head/scalp with conductive gel. These electrodes detect patterns of activation and electrical activity in the whole brain, made by the many neurones within your brain firing together. These patterns are represented as brain waves:
Alpha.
Beta.
Theta.
Delta.
The amplitude is the brain wave's size and intensity, and the frequency is the distance between each wave, showing the speed of activation. We can infer consciousness and brain activity by analysing brain waves.
EEGs are often used in sleep studies, as they can detect the changes in brain waves that indicate different stages of sleep.
If a person is suffering from a sleep disorder, an EEG can help identify where problems are occurring, detecting abnormal brain waves.
They can also be used in other disorders, highlighting their diagnostic properties.
Fig. 4: Brainwave EEG data over the course of ten seconds.
Event-related potentials (ERPs) are very similar to EEGs because they also use electrodes and record the tiny electrical changes in the neurons of the brain. The difference is that researchers present participants with a stimulus many times, and each wave response is added to a pool of data. This creates a smooth activation curve of the collected data, called statistical averaging.
Statistical averaging allows ERPs to remove background noise that has nothing to do with the stimulus, so researchers can say with greater certainty that activation is due to the stimulus and not just background noise. The waves have peaks and troughs that represent cognitive processes in the brain and are called event-related potentials.
ERPs are great for use in memory studies.
Fig. 5: An EEG measures brain activity using electrodes.
All of the techniques we have discussed thus far are techniques we can use to study the brain in relation to behaviour. We can infer function, and therefore behaviour, through analysing the brain structures, activity, and any abnormalities associated with a decline in function with these techniques.
For instance, Broca's and Wernicke's areas associated with language function in the brain were initially identified through post-mortems, as dysfunction in language abilities whilst the patients were alive were associated with lesions in these areas found when they had died.
fMRI scans show us functional areas without being invasive.
We can see how if someone were to flex their fingers, an fMRI will show areas of activity in the brain associated with this movement.
EEGs and ERPs can indicate behavioural responses to exposure to a stimulus, and also indicate how behavioural changes can be detected in those with certain disorders.
EEGs can be used to detect abnormal brain waves in patients with schizophrenia. Arora et al. (2021) investigated auditory hallucinations and changes in frequency bands of resting EEG data in hallucinating patients, non-hallucinating patients, and controls.
To give a few examples of how EEGs revealed information on schizophrenia, they found that:
Amongst other EEG data results.
Each method has its own strengths and weaknesses. To give a brief summary of each concerning their resolution:
Method | Technique description | Advantages | Disadvantages |
Post-mortem examinations | Fixation and examination of dead brain tissues. | High spatial resolution | Cannot prove the functions of brain regions (inference only) |
fMRI | Detection of the change in blood flow in the brain using a magnetic field. | High spatial resolutionNon-invasive | Poor temporal resolutionExpensive |
EEG | Detection of electric activity in the brain using electrodes placed on the scalp. | Good temporal resolution | Poor spatial resolution |
ERP | Detection of electric activity in the brain using electrodes placed on the scalp on repeated occasions to average the findings. | High temporal resolution | Poor spatial resolution |
There are many different methods to studying the brain. Some common examples are post mortem examinations (an older technique), fMRI scans, EEGs and ERPs, and computerised tomography scans (CT scans) and positron emission tomography scans (PET scans).
We typically study the brain by asking participants to perform a task and then measuring brain activity whilst they complete the task. Alternatively, we may give them a stimulus and measure brain activity during the stimulus. Post-mortems study the brain after death, usually done so if the patient has died due to trauma or damage to the brain.
There are many ways in which scientists study the brain. Post-mortems, fMRI, EEG/ERPs, and computerised tomography scans (CT scans) are a few examples.
These include post-mortem instruments used to extract and examine the brain, functional magnetic resonance imaging machines measure blood flow, and EEGs and ERPs, which use electrodes to measure brain activity.
What area of the brain was discovered using post mortems?
Broca’s area and the language centres.
What is spatial resolution?
Spatial resolution is the degree of accuracy that a technique achieves when examining brain activity.
What is temporal resolution?
Temporal resolution is the degree of accuracy in determining brain activity over time that the technique provides.
What is a post-mortem?
It is the examination of the body and brain after death.
Who typically carries out a post-mortem?
A pathologist.
Why is a chemical fixative used in post-mortems on the brain?
The brain is treated using a chemical fixative to make it firm so it can be handled and cut.
Already have an account? Log in
Open in AppThe first learning app that truly has everything you need to ace your exams in one place
Sign up to highlight and take notes. It’s 100% free.
Save explanations to your personalised space and access them anytime, anywhere!
Sign up with Email Sign up with AppleBy signing up, you agree to the Terms and Conditions and the Privacy Policy of StudySmarter.
Already have an account? Log in
Already have an account? Log in
The first learning app that truly has everything you need to ace your exams in one place
Already have an account? Log in