“Cognitive function” is a frequently encountered term in the realm of health and wellness. We may come across it verbatim, as in the example, “After experiencing a stroke, a person may lose some cognitive function.” But we also often see the related terms “cognitive decline,” as in the example, “My elderly mother is beginning to experience cognitive decline” …and “cognition,” as in, “He survived the head injury with no discernible changes in cognition.”
All of these terms pertain to the functions of the brain. But since the brain is involved in most aspects of our physiology, down to digestion, breathing, and pain, which processes are considered cognitive? Exactly what is cognitive function?
The Thinking Brain
The deeper role of brain activity in the proper functioning of our anatomy is excluded from the concept of cognition. Instead, what we mean by cognitive function is the varied and complex bundle of activities involved in how our brains interact with information about the world.
A StatPearls article from 2023 defines cognitive function as follows: “Cognition is the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses. It encompasses various aspects of high-level intellectual functions and processes such as attention, memory, knowledge, decision-making, planning, reasoning, judgment, perception comprehension, language, and visuospatial function. Cognitive processes use existing knowledge and generate new knowledge.”
Let’s look at each of those processes a bit more carefully:
- Attention is the ability to focus selectively on specific information while ignoring irrelevant, distracting stimuli, filtering and prioritizing certain things going on in the environment to engage with some and shut out others to better learn and process information. Attention may be sustained (specifically directed for a prolonged period) or divided (attending simultaneously to multiple stimuli). The capacity for attention is naturally limited in all humans but may be diminished by cognitive deficits.
- Knowledge is the construction and representation of information in memory, arrived at through such cognitive processes as attention, learning, and reasoning.
- Decision-making is the ability to deploy some set of criteria to select an option or a course of action from among two or more alternatives.
- Planning is the process whereby we achieve our outcomes through goal-setting, strategy, and action. Planning may be long-term or short-term, and while it may seem simple, it relies on several other cognitive functions.
- Reasoning is the ability to go beyond taking information at face value and instead to make inferences from it. When faced with a set of information or circumstances, a person may use their reasoning to generate expectations, assertions, or generalizations, and this may happen almost automatically or through sustained, intense, and conscious effort.
- Judgment is closely related to reasoning, planning, and decision-making. It consists of the ability to make an assessment based on available data. Our judgments are made through a process of weighing available information, considering context, evaluating potential solutions and pitfalls, and assessing probable outcomes.
- Perception comprehension is the process of making sense of the information we take in through our senses. In their raw forms, sensory stimuli have no meaning. For example, taken as purely sensory data, a particular series of sounds are nothing more than vibrations, but through perception comprehension we can understand that what we are hearing is music, and perhaps more specifically the opening notes of Bach’s Cello Suite No.1 in G Major.
- Language is, of course, the primary means through which humans communicate with each other. It is an essential form of cognition which is deeply intertwined with other cognitive processes including memory, reasoning, perception comprehension, and attention. Language is also central both to how we experience the world and how we interpret it. Psychologists are still exploring the nature of language, whether it is a part of the mind, a process of mind, or both.
- Visuospatial function is the ability to navigate the physical world through understanding the environment based on visual observations. Visuospatial function is naturally more developed in some people than others. For example, some people can easily imagine what an object would look like if it were rotated 90 degrees, while others struggle to do so. The vestibular system, located in the inner ear and responsible for balance, appears to play a significant role in visuospatial function.
Cognitive Problems
Any or all of the above aspects of cognitive function can be or can become impaired…from birth, temporarily, progressively, or permanently. As we get older, many of us begin to experience a drop-off in certain aspects of cognition, especially memory and attention. These changes may or may not be reason for concern. Some declines in memory are a normal part of aging. But if your deficits are more severe than should be expected for a person your age, yet do not interfere significantly with daily life, they may be classified as mild cognitive impairment (MCI). MCI sometimes (but certainly not always) progresses to a more severe deficit called dementia. If you’re concerned that your thinking and memory are getting worse, talk to your doctor, who can perform a quick cognitive test and, potentially, refer you to specialists who can perform a more thorough assessment. Even if you do have MCI or even dementia, getting an early diagnosis and starting treatment early can be enormously beneficial and preserve your quality of life for much longer than if you deny or try to hide your cognitive issues.
