Introduction:
Cognition is the act of processing knowledge, understanding through the mind, experiencing through senses, gaining knowledge, paying attention and memory, and coordinating the responses with the brain and the organs. Cognitive impairment can occur due to neurological disorders and other illnesses.
A cognitive screening test is done to assess cognitive functions like knowledge, memory, thought process, and judgment. The cognitive screening evaluates and characterizes episodes of confusion, sleep disorders, and loss of consciousness. Cognitive disorders like impairment of language, mentation (mental activity), and memory occur primarily due to disorders of the cerebral cortex (outer layer of the cerebrum).
What Does Cognitive Screening Comprise?
A thorough patient history and a proper clinical examination are made to perform a cognitive assessment. Through the history that comes in the patient's own words, the physician could assess the severity of the impairment. The following cognitive skills are tested during the cognitive screening:
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Language: Controlled oral word association and Boston naming tests are a few tests to assess language. The physician also evaluates language by asking the patients to name the objects and repeat or read words. Through language, disorders like aphasia can be diagnosed. Aphasia is characterized by the inability to communicate and often occurs after head injuries.
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Abstract Reasoning: It involves the ability to relate things and solve problems on a theoretical level. This will be done by the physician by asking them to explain similes and proverbs and by asking them to match objects that are similar. Verbal concept attainment tests and conceptual level analogy tests are a few tests to assess abstract reasoning.
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Executive Functions: This includes organizational skills to plan, execute and make a list of tasks. Mental flexibility is tested by asking the patients to name as many flowers as they know. It can also be done by asking the patient to follow a certain recipe for food.
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Concentration: Attention and concentration is tested by the physician throughout the interview. Sometimes the patients are asked to spell out words to assess concentration.
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Memory: Memory is assessed based on the patient's recalling capabilities. Memories can be short-term or long-term, and they are a bit complex, but they can be easily pinpointed from the patient’s history.
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Visuospatial Skills: This refers to the ability of the patient to study two and three-dimensional objects. It is tested by asking the patient to copy a diagram or block designs.
What Are Cognitive Screening Tests?
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Mini-Mental State Exam: It is an easy-to-use tool and can be finished in ten minutes. It is now less frequently used due to extra costs.
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General Practitioner Assessment of Cognition (GPCOG): It will help assess the cognitive functions by comparing answers given by the patient and answers of the family. This test will help identify dementia (a group of disorders affecting memory, and cognitive impairments, interfering with daily activities of living).
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Mini-Cog: It is a quick assessment and consists of two parts. A clock drawing test and a three-item recall test are conducted. This assesses the skills like language and visuospatial skills (one of the cognitive functions that will help distinguish between spatial and visual relationships among different objects, language, and executive function (cognitive function to execute a task in a planned manner by remembering the instructions and following a plan).
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Saint Louis University Mental Status Exam: This assessment is done to evaluate the patient's cognitive skills like memory, attention, executive function, and orientation of self with the environment. This test is specially designed for veterans.
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Montreal Cognitive Assessment (MoCA): This is a popular test that can be done in ten minutes. Skills like attention, visuospatial skills, language, delayed recall, abstract reasoning, orientation, and executive function are assessed in this test.
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Memory Impairment Screen: It is a fast tool to assess memory. It is used as a preliminary assessment tool for patients who have problems with recalling things. It can be used as an adjunct with the other screening tests.
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Functional Activities Questionnaire: This test comprises the time and the extent of efforts taken by the patient to perform daily activities such as taking a shower, brushing, cleaning, and dressing up. This will help assess the patient’s cognitive skills like executive function, memory, attention, abstract reasoning, and concentration.
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Abbreviated Mental Test: It is a quick screening tool used in the geriatric population.
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Six-Item Screener: The patient is asked to recall the year, month, and days of the week. This three-word recall is used as a screening tool.
What Are the Tests Carried Out to Assess Cognitive Impairment?
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EEG (Electroencephalogram): It is used in defining the nature of the cognitive impairment and is very critical of consciousness. It also helps distinguish between various seizure disorders from metabolic disturbances. It also helps to identify focal lesions, sleep disorders, and hysteria (unmanageable excess emotional feelings). Only clinical testing of thinking and memory can provide more information than EEG (electroencephalogram). EEG is considered the most precise laboratory investigation that helps to assess cortical function. Characteristic abnormalities in the EEG will help physicians define the nature of the disorders that are causing impaired mentation. They help in diagnosing conditions with altered mentation that include chronic infection, Alzheimer’s disease (a degenerative condition of the brain that impairs memory and other mental functions), subdural hematoma (bleeding inside the brain), ischemic vascular disease (damage to the blood vessels of the heart due to plaque build-up), and frontal lobe mass lesions.
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Polysomnography: This is another study that provides a precise assessment and helps to characterize different types of sleep disorders. They also help find the specific nature and help physicians plan treatment accordingly.
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SEPs (Somatosensory Evoked Potentials) And Brain Stem Auditory Evoked Potentials (BAEPs): These are tests that can help determine if central sensory pathways are functioning normally and intact. Patients in a coma can be assessed by this test. SEPs help finds the severity of impairments post-head trauma. Therefore prompt diagnosis and appropriate treatment plan have been made possible.
Conclusion:
Cognitive screening tools are designed especially for people with cognitive impairments, and they are easy to use and time-saving. These screening tests, however, do not apply to people without cognitive disabilities. Certain tests like Mini-cog are still under development and cannot be fully relied upon. Standardizing the tests to assess neurocognitive functions can help in appropriate diagnosis.