Ways of Studying the Brain
Advances in science and technology have produced ever more sophisticated and precise methods
of studying the brain. Some modern scanning techniques are able to record global neural activity
through the assessment of brainwave patterns. Other techniques, meanwhile, are able to home
in on activity in specific parts of the brain as the brain performs certain tasks and processes. The
three scanning techniques stated in the specification are:
- Functional magnetic resonance imaging (fMRI)
- Electroencephalogram (EEGs)
- Event-related potentials (ERPs)
Another more traditional way of investigating the brain – the post-mortem examination – is also
considered.
Functional Magnetic Resonance Imaging (fMRI)
- Functional magnetic resonance imaging (fMRI) is a technique for indirectly measuring the
electrical activity of neurons by recording changes in brain blood flow while a person
performs a task
- fMRI works by using magnetic field and radio waves to detect changes in both blood
oxygenation and flow that occur as a result of neural (brain) activity in specific parts of the
brain. It gives a moving picture of the brain.
- When a brain area is more active, it consumes more oxygen and to meet this increased
demand, blood flow is directed to the active area, delivering oxygen in the red blood cells
(known as the haemondynamic response).
- fMRI produces three-dimensional images (activation maps) showing which parts of the
brain are involved in a particular mental activity and this has important implications for
our understanding of localisation of function
Electroencephalogram (EEGs)
- Electroencephalogram (EEG) directly measures electrical (neuronal) activity within the
brain via electrodes that are fixed to an individual’s scalp using a skull cap.
- The scan recording represents the brainwave patterns that are generated from the action
of thousands of neurons, providing an overall account of brain activity.
- EEG is a recording of general brain activity, usually linked to states such as sleep and
arousal
- EEG is often used by clinicians as a diagnostic tool as unusual arrhythmic patterns of
activity (i.e. no particular rhythm) may indicate neurological abnormalities such as
epilepsy, tumours or some sleep disorders.
Event-related Potentials (ERPs)
, - ERPs use similar equipment to EEGs. ERPs use electrodes that are fixed to an individual’s
scalp to detect electrical (neuronal) activity in response to a specific stimulus (a
picture/sound/specific task) introduced by the researcher.
- To establish a specific response to a target stimulus requires many presentations of
the stimulus and these responses are then averaged together. Any extraneous neural
activity that is not related to the specific stimulus will not occur consistently, whereas
activity linked to the stimulus will.
Post-mortem Examinations
- This is a technique involving the analysis of a person’s brain following their death to try and
correlate structural abnormalities/damage to behavioural changes.
- In psychological research, individuals whose brains are subject to a post-mortem
examination are likely to have been those who have a rare disorder and have experienced
unusual deficits in cognitive processes or behaviour during their lifetime.
- Areas of damage within the brain are examined after death as a means of establishing
the likely cause of the affliction the person experienced.
- This may also involve comparison with a neurotypical brain in order to ascertain the
extent of the difference.
A03
Key ways to evaluate/compare the different methods of studying the brain:
- Invasive/non-invasive technique (does it involve the insertion of instruments into the
body, or does it expose the brain to potentially harmful radiation?)
- Spatial resolution (refers to the smallest feature, or measurement, that a scanner can
detect/accuracy of the image – how clear it is)
- Temporal resolution (how quickly the scanner can detect changes in brain activity)
- Whether it directly measures brain (electrical/neural) activity
- Whether it measures superficial/outer regions or deeper/inner regions of the brain
- Expense
FMRIs
Point Evidence Conclusion
One key strength of fMRI is, fMRI does not rely on the This is a strength as it
unlike other scanning use of harmful radiation or means that fMRI can safely
techniques such as PET, it involve the insertion of provide a clear picture of
is non-invasive. instruments into the brain activity.
brain/body. If administered
correctly, it is virtually risk-
free and straightforward to
use.
Advances in science and technology have produced ever more sophisticated and precise methods
of studying the brain. Some modern scanning techniques are able to record global neural activity
through the assessment of brainwave patterns. Other techniques, meanwhile, are able to home
in on activity in specific parts of the brain as the brain performs certain tasks and processes. The
three scanning techniques stated in the specification are:
- Functional magnetic resonance imaging (fMRI)
- Electroencephalogram (EEGs)
- Event-related potentials (ERPs)
Another more traditional way of investigating the brain – the post-mortem examination – is also
considered.
Functional Magnetic Resonance Imaging (fMRI)
- Functional magnetic resonance imaging (fMRI) is a technique for indirectly measuring the
electrical activity of neurons by recording changes in brain blood flow while a person
performs a task
- fMRI works by using magnetic field and radio waves to detect changes in both blood
oxygenation and flow that occur as a result of neural (brain) activity in specific parts of the
brain. It gives a moving picture of the brain.
- When a brain area is more active, it consumes more oxygen and to meet this increased
demand, blood flow is directed to the active area, delivering oxygen in the red blood cells
(known as the haemondynamic response).
- fMRI produces three-dimensional images (activation maps) showing which parts of the
brain are involved in a particular mental activity and this has important implications for
our understanding of localisation of function
Electroencephalogram (EEGs)
- Electroencephalogram (EEG) directly measures electrical (neuronal) activity within the
brain via electrodes that are fixed to an individual’s scalp using a skull cap.
- The scan recording represents the brainwave patterns that are generated from the action
of thousands of neurons, providing an overall account of brain activity.
- EEG is a recording of general brain activity, usually linked to states such as sleep and
arousal
- EEG is often used by clinicians as a diagnostic tool as unusual arrhythmic patterns of
activity (i.e. no particular rhythm) may indicate neurological abnormalities such as
epilepsy, tumours or some sleep disorders.
Event-related Potentials (ERPs)
, - ERPs use similar equipment to EEGs. ERPs use electrodes that are fixed to an individual’s
scalp to detect electrical (neuronal) activity in response to a specific stimulus (a
picture/sound/specific task) introduced by the researcher.
- To establish a specific response to a target stimulus requires many presentations of
the stimulus and these responses are then averaged together. Any extraneous neural
activity that is not related to the specific stimulus will not occur consistently, whereas
activity linked to the stimulus will.
Post-mortem Examinations
- This is a technique involving the analysis of a person’s brain following their death to try and
correlate structural abnormalities/damage to behavioural changes.
- In psychological research, individuals whose brains are subject to a post-mortem
examination are likely to have been those who have a rare disorder and have experienced
unusual deficits in cognitive processes or behaviour during their lifetime.
- Areas of damage within the brain are examined after death as a means of establishing
the likely cause of the affliction the person experienced.
- This may also involve comparison with a neurotypical brain in order to ascertain the
extent of the difference.
A03
Key ways to evaluate/compare the different methods of studying the brain:
- Invasive/non-invasive technique (does it involve the insertion of instruments into the
body, or does it expose the brain to potentially harmful radiation?)
- Spatial resolution (refers to the smallest feature, or measurement, that a scanner can
detect/accuracy of the image – how clear it is)
- Temporal resolution (how quickly the scanner can detect changes in brain activity)
- Whether it directly measures brain (electrical/neural) activity
- Whether it measures superficial/outer regions or deeper/inner regions of the brain
- Expense
FMRIs
Point Evidence Conclusion
One key strength of fMRI is, fMRI does not rely on the This is a strength as it
unlike other scanning use of harmful radiation or means that fMRI can safely
techniques such as PET, it involve the insertion of provide a clear picture of
is non-invasive. instruments into the brain activity.
brain/body. If administered
correctly, it is virtually risk-
free and straightforward to
use.
