Outline and evaluate one or more ways of studying the brain (8 marks)
An event-related potential (ERP) is a non-invasive way of studying the brain. This method of study
involves attaching electrodes to the scalp of the participant and presenting them with a stimulus.
The electrodes measure voltage changes in the brain, allowing them to record the activation of
different areas of the brain in response to a stimulus. Whilst being really similar to EEG, ERP differs in
the fact that it is able to identify exactly which parts of the brain are activated. For this to work, the
stimulus is shown the same stimulus hundreds of times, and an average is taken of all the scans to
determine the actual part of the brain that is used, eliminating any external stimuli that their brain
may respond to. ERPs use latency to detect which mental processes are occurring as well as where
they may be occurring. Latency is the time between the presentation of the stimulus and the
recorded reaction. There are two types of latency that allow the researchers to determine the type
of brain activity. These are waves that occur before and waves that occur after 100 milliseconds
when the stimulus was presented. Waves under 100 milliseconds are referred to as sensory ERPs, as
they suggest that the response was sensory. Waves after 100 milliseconds are known as cognitive
ERPs as the delay suggests that there was some cognitive activity before the response to the
stimulus.
A strength of ERP is that it is relatively non-invasive, albeit uncomfortable. The procedure involves
no internal activity such as instruments being inserted into the body, and no radiation is involved so
the patient doesn’t become vulnerable to radiation poisoning. This is a strength because this method
of studying the brain does not cause any harm to the patient, short term or long term. This gives
researchers an ideal way to study the brain, whilst keeping to ethical guidelines by not harming their
patient either mentally or physically.
A weakness of ERP is that it is incredibly difficult to standardise each condition. There are many
extraneous variables that can affect the activity shown in the scans, and as the brain subconsciously
picks up on every stimulus around it, it is impossible to completely eliminate every other variable.
The lack of standardisation makes it difficult to produce reliable research findings.
An event-related potential (ERP) is a non-invasive way of studying the brain. This method of study
involves attaching electrodes to the scalp of the participant and presenting them with a stimulus.
The electrodes measure voltage changes in the brain, allowing them to record the activation of
different areas of the brain in response to a stimulus. Whilst being really similar to EEG, ERP differs in
the fact that it is able to identify exactly which parts of the brain are activated. For this to work, the
stimulus is shown the same stimulus hundreds of times, and an average is taken of all the scans to
determine the actual part of the brain that is used, eliminating any external stimuli that their brain
may respond to. ERPs use latency to detect which mental processes are occurring as well as where
they may be occurring. Latency is the time between the presentation of the stimulus and the
recorded reaction. There are two types of latency that allow the researchers to determine the type
of brain activity. These are waves that occur before and waves that occur after 100 milliseconds
when the stimulus was presented. Waves under 100 milliseconds are referred to as sensory ERPs, as
they suggest that the response was sensory. Waves after 100 milliseconds are known as cognitive
ERPs as the delay suggests that there was some cognitive activity before the response to the
stimulus.
A strength of ERP is that it is relatively non-invasive, albeit uncomfortable. The procedure involves
no internal activity such as instruments being inserted into the body, and no radiation is involved so
the patient doesn’t become vulnerable to radiation poisoning. This is a strength because this method
of studying the brain does not cause any harm to the patient, short term or long term. This gives
researchers an ideal way to study the brain, whilst keeping to ethical guidelines by not harming their
patient either mentally or physically.
A weakness of ERP is that it is incredibly difficult to standardise each condition. There are many
extraneous variables that can affect the activity shown in the scans, and as the brain subconsciously
picks up on every stimulus around it, it is impossible to completely eliminate every other variable.
The lack of standardisation makes it difficult to produce reliable research findings.
