Recent research indicates that the number of words a person can list in a specific category within just fifteen seconds may serve as a strong indicator of their broader cognitive health. The study suggests that the initial burst of word retrieval during a verbal fluency task is a more effective predictor of cognitive status than the performance over a full minute. These findings were published in Experimental Aging Research.
The prevalence of dementia is a growing global health concern. Current estimates suggest that roughly 50 million people live with dementia today, and this number is projected to triple by the year 2050. The condition is characterized by a progressive decline in cognitive abilities that often begins years before a clinical diagnosis is made.
Subclinical changes in brain health can commence more than two decades prior to the manifestation of obvious symptoms. Medical professionals prioritize the early detection of these subtle changes to manage neurodegenerative diseases effectively. Since age is the primary risk factor for cognitive decline, evaluating middle-aged adults is vital for understanding how these conditions progress.
Cognitive performance is often assessed independently of mental health, but evidence suggests a connection between the two. Issues with emotional regulation can impair executive functions, which are the mental skills that include working memory and flexible thinking. Conditions such as depression and anxiety have been linked to deficits in these cognitive areas.
The authors of the new study aimed to integrate these often-separated fields of inquiry. They sought to analyze the relationship between the timing of word retrieval, demographic factors, and the presence of mental disorders. The goal was to determine how these variables interact to influence cognitive performance in Spanish-speaking adults.
“Neurodegenerative diseases affect numerous individuals worldwide, and the early detection of their signs facilitates prompt and effective treatment, thereby enhancing the quality of life for those affected by these conditions,” said study author Susana A. Castro-Chavira, a lecturer at Anahuac University Campus Queretaro and associate researcher at National Autonomous University of Mexico.
“A comprehensive understanding of the dynamics and characteristics of cognitive change is essential for accurately identifying markers that indicate the need for intervention to delay or slow the progression of cognitive decline. Our study seeks to examine the associations between cognitive status and neuropsychiatric morbidity, while also exploring how these associations influence performance on a semantic verbal fluency task.”
The research team recruited 74 participants through social media platforms. The sample included men and women over the age of 40, with a median age of 56. All participants were native Spanish speakers of Latin-American ethnicity.
Data collection took place between April 2021 and March 2022. Due to restrictions imposed by the COVID-19 pandemic, the researchers adapted all assessments for online administration. Participants completed questionnaires and interviews via Google Forms and Zoom.
The researchers gathered detailed demographic data, including age, sex, and years of education. The sample was relatively highly educated, with a median of 18.7 years of schooling. This is notably higher than the average for the general Mexican population.
Participants completed the Short Form-36 Health Survey to assess their perception of their own health. This survey covers eight dimensions, including physical functioning, vitality, and general mental health. It provides a snapshot of how individuals view their quality of life.
The research team screened for mental disorders using the Mini International Psychiatric Interview. This structured interview evaluates the presence of various psychiatric conditions. They also used the Hamilton Anxiety Scale and the Beck Depression Scale to measure the severity of anxiety and depression symptoms.
To measure cognitive status, the researchers administered the Mini-Mental State Examination and the Montreal Cognitive Assessment. These tests are standard tools used to screen for mild cognitive impairment and dementia. They assess skills such as memory, attention, language, and orientation.
The core of the experiment was the Semantic Verbal Fluency task. The researchers asked participants to list as many words as possible belonging to specific categories within one minute. The categories included Animals, Fruit, Professions, Food dishes, and Furniture.
The researchers recorded the responses and analyzed them in four separate fifteen-second intervals. They counted the number of correct words produced in the first, second, third, and fourth quarters of the minute. This allowed them to observe the “temporal course” of word retrieval.
They also tracked errors, such as repeating a word or listing a word that did not belong to the category. This granular analysis provided data on how word production changes as the task progresses. The team then used statistical methods to identify which time intervals were most mathematically significant.
The statistical analysis revealed that the first fifteen-second period contained the most significant data. A principal component analysis showed that the number of words produced in this first quarter explained the largest portion of the variance in test scores. This initial burst appears to represent the most efficient phase of information search and retrieval.
When the researchers ran regression models, they found that this first fifteen-second interval was the best predictor of cognitive status. Along with age, the performance in this initial timeframe strongly predicted scores on both the Mini-Mental State Examination and the Montreal Cognitive Assessment.
The researchers also examined the relationship between mental disorders and task performance. The results showed that participants with mental health conditions generally performed worse on the verbal fluency task. Negative correlations appeared between mental disorder incidence and the number of words generated.
Specific patterns emerged regarding depression and anxiety. Participants with depressive symptoms, such as dysthymia, tended to produce fewer words in the first fifteen seconds of certain categories. This aligns with previous research suggesting that depression can slow speech and cause longer pauses.
Anxiety also appeared to interfere with performance. The data indicated a negative association between anxiety levels and word production in the later stages of the task. High anxiety may impair processing efficiency, making it harder for individuals to sustain their focus and search strategies over time.
“Mental health care plays a crucial role in ensuring a high quality of life throughout adulthood and in reducing the risk of cognitive decline, to which individuals become increasingly vulnerable as they age,” Castro-Chavira told PsyPost.
Despite these associations, the regression models indicated that age remained the strongest predictor for the incidence of mental disorders. This suggests that as individuals get older, their general susceptibility to psychopathology may increase. The verbal fluency task was less effective at predicting mental disorders than it was at predicting cognitive decline.
“There are risk factors for cognitive decline that cannot be controlled or avoided, such as aging or genetic susceptibility, but also there are protective measures to decrease such risk,” Castro-Chavira noted. “Good sleep, good nutrition, continuous physical and cognitive activity, and good mental health care makes the individual better prepared for the increased vulnerability for cognitive decline that comes with age.”
The researchers noted a discrepancy between the two cognitive screening tools used. The Mini-Mental State Examination categorized most participants as having normal cognitive function. In contrast, the Montreal Cognitive Assessment suggested that a majority had mild cognitive impairment.
This difference may stem from the difficulty level of the Montreal Cognitive Assessment or issues with its translation. The authors suggest that the specific version used might have included confusing items. This highlights the importance of calibrating cognitive tests for specific cultural and linguistic populations.
The study has some limitations. The sample size was relatively small, consisting of only 74 individuals. This limits the ability to generalize the findings to the broader population.
The online nature of the study also presented challenges. Conducting assessments via video calls prevents the full control of the environment that is possible in a laboratory setting. External distractions or technical issues could have influenced the results.
Additionally, the high educational level of the participants may have skewed the data. Education is known to be a protective factor against cognitive decline. A sample with a more diverse educational background might have yielded different results.
Future research should aim to replicate these findings with larger and more diverse groups. Comparisons between online and in-person evaluations would help validate the reliability of remote testing. The authors also express an interest in incorporating biological markers to better understand the mechanisms behind their findings.
The integration of mental health assessments with cognitive testing remains a priority. Mental disorders are often chronic and comorbid. Understanding how they interact with cognitive aging could lead to better prevention strategies.
Overall, the study provides evidence that the semantic verbal fluency task is a quick and effective tool. Specifically, the first fifteen seconds of the task appear to hold the most diagnostic value. This brief window into memory retrieval could help clinicians detect early signs of cognitive decline.
The study, “Cognitive Status and Mental Disorder Morbidity are Differentially Associated with Semantic Verbal Fluency in Middle-Aged and Older Adults,” was authored by Gabriela Maldonado-Vargas, Hebert Luis Hernández-Montiel, Sofía Díaz-Cintra, Julián Valeriano Reyes-López, and Susana A. Castro-Chavira.
