Cognitive Neuroscience

Cognitive Neuroscience in Psychology

Cognitive neuroscience works by analysing the brain with neural imaging techniques and comparing findings of neural imaging to behavioural data.

The combination of 'hard' scientific elements (direct measurement and observation) with the 'soft' scientific aspects of psychology, such as talk therapy, has further legitimised psychology and its place as a science in the academic and scientific communities. Let's look at some of these neural imaging techniques and explore how they work.

An MRI machine allows glimpses into the inner workings of the body | Wikimedia Commons

Positron Emission Tomography (PET) scans

PET scans work by identifying the presence of radioactive tracers. Patients undergoing a PET scan have the tracer injected into their blood. When a quantity of blood collects in a particular area due to increased blood flow, the PET scan can detect where the blood is going.

If they had trouble recalling such memories and their doctor performed a PET scan, they may find a dysfunctional amount of activity in that brain area.

The PET scan is beneficial to cognitive neuroscience as it allows instant, real-time imaging of the brain and its functions, which can be used to gain a deeper understanding of a patient's condition and the brain.

Computerised Tomography (CT) scans

CT scans work by using X-Rays to create an accurate 3D model of someone's brain. This is done by emitting X-Rays onto the brain. Unlike a PET scan, which produces a real-time brain activity image, CT scans produce a detailed snapshot of the brain's structure.

The CT scan is helpful in cognitive neuroscience because it allows doctors and researchers to observe the brain's physical condition directly. This can be useful for treating a patient with specific brain trauma or understanding and comparing different brains. CT scans are not typically performed on children and pregnant people, as they require X-rays, which are high-energy waves of radiation that come with risk.

Magnetic Resonance Imaging (MRI) and Functional Magnetic Resonance Imaging (fMRI) scans

MRI scans show a real-time brain image by using a combination of radio waves and magnetic fields that affect hydrogen nuclei in the body (protons).

fMRI is a similar scan, but instead of simply creating an image, it allows the brain's activity to be observed by scanning metabolic function. During fMRI scans, patients are often given prompts ranging from questions and orders to visual stimuli. The activity in the brain is then observed, as different activities and prompts will elicit activity in the various parts of the brain.

• Much like the PET scan, the fMRI scan allows real-time brain activity observation, but unlike the PET scan, no exposure to radiation is required. This is a significant advantage for the fMRI, as it is healthier for the patient and allows numerous brain scans instead of just one.
• In practice, even though the PET scan produces clearer images than fMRI, the ability for fMRI to be repeated results in clearer images of the brain.

Cognitive Neuroscience Psychology Example

As an elementary explanation, cognitive neuroscience means that the brain's underlying structures and processes determine how we act and think. Let's look at some real-world examples of cognitive neuroscience, starting with the case of Phineas Gage.

Cognitive Neuroscience Experiments: Phineas Gage

Phineas Gage was a man who worked on railroad construction in the 19th century in America. As part of his job, Gage had to create holes in the ground using dynamite to build a foundation for new train tracks. Part of this process was packing the explosives with a metal rod. Still, unfortunately for Phineas, the explosives were triggered by this action, and the metal rod was sent through his skull at high speed, completely entering and exiting the left side of his brain.

Miraculously, Phineas survived this event, despite serious injuries, bleeding and damage to his brain. However, he was soon considered well enough to start working again.

Despite his physical condition improving, Gage was profoundly psychologically changed by the incident. Gage changed from a man observed to be polite and hardworking to an indecisive, aggressive and rude man. This change was so marked that Harlow, the doctor working with him then, noted that friends and family considered him 'No longer Gage'.

A metal rod was sent through Phineas Gage's frontal lobe І Wikimedia commons

The physical damage he suffered to his brain transformed his personality entirely:

• Harlow explicitly suggested that the injury was the underlying cause of his radical personality shift.

While in Gage's day, the methods by which the brain could be understood and observed were very limited, we've gained a more scientific understanding of what happened through modern imaging techniques.

Sadly, while Gage did die twelve years after the incident, Harlow was able to provide his skull to researchers, allowing Gage's misfortune to assist psychologists.

Tulving's gold memory study

Another example of cognitive neuroscience research is Tulving's 'gold' memory study. This case study aimed to find a link between different types of memories and respective activity in the brain.

Method

Six participants were instructed to sit or lie on a sofa, close their eyes and imagine a memory on any topic they wish. After a minute of this, Tulving had the participants injected with a tracer - a radioactive gold isotope that would be highlighted by a PET scan, which intended to show Tulving which areas of the brain were most active during the imagining of different memories.

Participants did this eight times.

Findings

While three participants were not included due to their inconsistent results, the other three demonstrated a marked difference in blood flow, which would demonstrate differing brain activity.

The study showed that when semantic memories were thought of (i.e, memories concerned with meaning) the cerebral cortex's parietal and occipital lobes were highlighted, but when episodic memories were thought of (i.e, memories concerned with events) the temporal and frontal lobes were highlighted.

Conclusion

Tulving concluded that based on his findings and observations, different types of memories prompted more activity in differing brain areas.

Practical Application of Cognitive Neuroscience: Neurological Damage

Neurological damage and the diagnosis and treatment of said damage are examples of the practical applications of cognitive neuroscience.

Examples of neurological damage include:

• Strokes affecting particular areas of the brain, disrupting the function
• Visual agnosia, where a patient is unable to make sense of visual information they are perceiving
• Prosopagnosia, where a patient is unable to recognise faces despite being able to perceive them visually
• Prefrontal cortex damage, associated with impulse control and personality expression

Cognitive neuroscience, through the methods detailed above, can identify areas of possible neurological damage and assess the best way to treat the areas of damage, all whilst monitoring the progression of the injury and disease and the effects of the treatment plans.