1 Contextualizing Cognitive Neuroscience

What is Cognitive Neuroscience?

“Nature in her unfathomable designs has mixed us of clay and flame, of brain and mind, that the two things hang indubitably together and determine each other’s being, but how or why, no mortal may ever know.” – W. James (1918)

Contrary to William James’ belief, research in the past 50 years has offered great insight into the relationship between the brain, the mind, and how they are connected and how they are separate. We have been able to identify the regions of the brain that are involved in decision making, what structures are necessary to produce speech, and what networks are responsible for detecting and prioritizing stimuli in our environments. Through the collaboration of various scientific domains, such as cognitive psychology, neuroscience, computer science, and physics, we have begun to understand the complex underlying mechanisms of mental processes.

This interdisciplinary field of study has been appropriately coined Cognitive neuroscience , and is defined as the scientific study of brain-based mechanisms that facilitate mental processes, including memory, perception, and reasoning. The human brain performs all of these functions, and many more, on a daily basis. Gaining insight into the structures responsible for particular cognitive processes can allow us to better understand Cognitive deficits , and the underlying differences that may cause such brain impairment

What Can We Learn From Cognitive Neuroscience?

Before brain imaging tools (see chapter 3),  the bulk of the learning came from studying patients. One of the most famous patients, referenced in nearly all cognitive and neuroscience textbooks, is known as H.M.

H.M. received an experimental surgery involving the bilateral removal of his hippocampus, a procedure called a bilateral medial temporal lobectomy in an effort to reduce his seizures. With the removal of these structures, he experienced extreme Anterograde amnesia , (an inability to form new memories). While most of his memories prior to the surgery remained intact, researchers that worked with him had to reintroduce themselves to him everyday, and he was considered ‘frozen in time’. H.M. was unable to recall things he had read or people he had met after his surgery, but further neuropsychological testing determined that he could still learn unconsciously. While most of H.M’s cognitive abilities were preserved following the surgery, he experienced minor retrograde amnesia and profound anterograde amnesia meaning he completely lost the ability to form new memories.  H.M. showed marked improvement on complex tasks (such as drawing a star while looking into a mirror), despite having no memory of ever completing these tasks! The famous example of H.M. demonstrates that there is much to be learned and revealed by studying cognitive neuroscience.

One researcher who studied H.M. extensively is the prominent British-Canadian Brenda Milner. After studying at Cambridge University, Dr. Milner studied at McGill University under Donald Hebb and worked at the Montreal Neurological Institute-Hospital. She briefly summarized H.M.’s case by saying “To see that H.M. had learned the task perfectly but with absolutely no awareness that he had done it before was an amazing dissociation. If you want to know what was an exciting moment of my life, that was one” (Brenda Milner | The Neuro – McGill University, n.d.). Her work examining epileptic patients, brain lesions, and memory has earned her numerous awards, including membership in the Royal Society of Canada and a Lifetime Achievement Award from the Canadian Association for Neuroscience.

As seen in the example of H.M., much that we have learnt in the field of cognitive neuroscience has come from brain injuries and abnormalities. Examining these differences, can give insight into key functions of the brain. Studying the case of H.M. and his condition revealed the existence of different modes of memory (declarative and nondeclarative), and that the hippocampus is integral for memory storage. While the study of H.M. showed that structures play a key role in cognitive functions, other case studies have highlighted that the tissue connecting different brain structures may be equally important. Take, for example, the study of Split brain patients.

Split brain patients are individuals who have had the connection between their hemispheres severed (either through surgery). Severing the connection of the two hemispheres, a white matter bundle known as the corpus callosum depicted in the following image, prevents the two halves of the brain from communicating. This prevented seizures from traversing brain hemispheres, reducing the likelihood of an individual  losing consciousness when experiencing a seizure. While this surgery typically was successful by that definition, other complications arose. For example, someone with a split brain might be buttoning up a shirt with one hand while their other hand unbuttons it! This is known as Alien hand syndrome, where a hand seems to have a “mind of its own”, this highlights the importance of interhemispheric communication to everyday function. This is another piece of the human puzzle that we have learned from cognitive neuroscience.

Studying cognitive neuroscience also informs our understanding of Functional specialization . One part of the brain can function well and another area can have severe cognitive deficits. Further caveats about the limitations of studying functional specialization will be discussed in later chapters.

Hopefully, this section has highlighted that we can learn numerous things about the brain (e.g., specific structures and the different roles of different matter), and about cognition more broadly (e.g., the different types of memory that exist). However, there are still many more questions that remain to be answered about the mechanisms that underlie cognitive processes.

Critical Thinking About Cognitive Neuroscience 

While cognitive neuroscience has the power to answer many questions, it, like any other field of study, has several key limitations.

On a broader scale, racism is a highly prevalent issue that is seen in neuroscience research. Founded in white supremacy, neuroscience both historically excludes BIPOC (Black, Indigenous, People of Colour) researchers (as seen by their underrepresentation in university faculties), and has also been used to further marginalize members of minorities (e.g., phrenology data being altered to justify slavery). Being cognizant of this history, and vigilant to the lasting impacts, is a foundational piece of conducting ethical neuroscientific research that can benefit all.

Conducting ethical neuroscience research involves including minority groups. While the argument has been made that excluding BIPOC participants from research can reduce their exposure to further harmful research experiences, it restricts them from benefiting from the knowledge that comes from this research. Whenever possible, balance must be applied to both reduce the toll that is placed on minority communities, as well as to maximize their benefit. This philosophy applies to cognitive neuroscience research, as well as all other domains of clinical and biomedical research.

One way to ensure that all groups can benefit research is to improve the diversity of the individuals conducting it. Including racial, cultural, gender, and sexual diversity in research is crucial for numerous reasons, and increases the skills and expertise of a research team. Improved cultural sensitivity and awareness further increases the likelihood of ethical research, and lived experiences may inform both research questions and methodology. Including research practices from minority groups (e.g., Etuaptmumk, also known as two-eyed seeing) is both an investment in more inclusive research, and additionally serves to recognize the value of diverse frameworks.

Summary and Conclusions

In this chapter, we covered some key points, for example that cognitive neuroscience is the study of brain-based mechanisms that facilitate all mental processes, including, but not limited to, memory, perception, and reasoning. We highlighted that cognitive neuroscience research can tell us lots of information about the brain (structural and functional), but that much work remains to elucidate the relationship between the brain and cognitive processes. Several limitations of this research (such as the overrepresentation of incidental findings and racism) were also discussed, and should be considered in further chapters as well as future research.

Key Names/Terms

 Alien hand syndrome

Anterograde amnesia

Cognitive deficits

Cognitive neuroscince

Functional specialization

Split brain