Influence of Age on Language Abilities

Influence of Age on Language Abilities

After the drastic growth spurts of infancy, childhood, and adolescent years, the brain reaches the peak of its performance at 25 years. At this time, the brain is the heaviest (1.3 kg) and strongest it will ever be at recalling, cross-referencing, and storing information (Gauvrit et al., 2017). These abilities, research shows, begin to deteriorate in the 30s through to the senior years (above 65). If this argument is anything to go by, then it means the brain's ability to comprehend, internalize, and produce language should also fade. Assuming that 25 – 35 years is the peak performance period, it would imply that the years before 25 (developmental years) have stronger language abilities while the years beyond 35 should demonstrate a reduction in language development ability.

In other words, children and adolescents have a stronger hand while senior citizens have a lower hand, based on the progressive deterioration of brain activities across the human development cycle. However, mixed research outcomes suggest that, when it comes to language abilities, this is not necessarily the case; those adults are equally capable of language abilities. These outcomes suggest that there is no definitive answer to whether language abilities improve or decline with age. Therefore, the purpose of the current paper is to review current primary research literature to argue that language ability declines, and does not improve, with age.

Methodology

            The current study aims to internalize primary research outcomes that have attempted to answer the current research question or have findings that may influence internal discussions. These articles were obtained from online databases, including PsychINFO, PubMed, Psychology database, linguistic database, and Linguistic and Language Behavior Abstracts (LLBA). These databases were preferred because they collected on human development, psychology, brain development, and linguistics, among others, key domains that inform the current paper. Using keywords like age, language, language ability, brain development, and language behavior, 68 articles were obtained. Thirty-eight articles were ignored because they did not have primary research findings. A further 20 did not meet the age criteria, which required articles published within the past five years. Such articles are vital because they provide the newest or improved information. Thus, the current paper relied on these ten articles to support the thesis, as discussed in the literature review section that follows.

Literature Review

Language Development in Children: Acquisition of Foreign Language

            In recent years, age has become a critical factor in determining a language learner's success and acquisition of a foreign language. This assumption correlates with the Critical Period Hypothesis, which posits that early childhood years are crucial times in which an individual can seamlessly acquire a first language if an adequate stimulus is presented consistent with dramatic neuroplasticity (Singleton & Le'sniewska, 2021). However, infancy and childhood are not definitive but classified on a scale based on age. Several research studies have attempted to show that children at different ages show different language abilities in childhood. For instance, Hartshorne, Tenenbaum, and Pinker (2018) premised that people who learn a second language in childhood speak the same as native speakers while those who learn in later stages of development are often saddled with conspicuous grammatical errors and accents. The authors asserted that children learn language more easily than adults based on this assertion.

            In their study, Hartshorne, Tenenbaum, and Pinker (2018), 669,800 participants were involved who were demographically diverse. Thirty-eight languages were represented by at least 1000 native speakers, excluding individuals with multiple native languages. A shotgun approach was utilized to assess syntax using miscellaneous items fitted into a short quiz. The approach addressed phenomena like clefting, passivization, relative clause, use of prepositions, subcategorization of verb syntax, and sequence of tenses, among others. Findings from the study suggest that the Critical period theory holds: that the youthful stages of human development provide the ideal conditions for maximum language abilities compared to adulthood and senior citizen stages. Thus, childhood is a critical period in which a second language can easily be acquired efficiently.

            In a different study with similar outcomes, albeit with a different research approach, Wang et al. (2022) concluded that language ability improves with increased age among children. The study involved the examination of a longitudinal neuroimaging dataset in language processing among children aged between 5 and 9 years. Structural magnetic resonance imaging (MRI), task-based functional MRI (fMRI), parental questionnaires, and a battery of psycho-educational assessments were utilized to collect data from and follow up on 322 children. Areas of investigation included phonological, semantic, and syntactic processing. A key outcome was that the older the child, the better their abilities. A critical difference between this study and work by Hartshorne, Tenenbaum, and Pinker (2018), aside from the methodology utilized, is that while the latter focuses on the entire development cycle, the former is confined to children between 5 and 9 years. However, the similarity in findings is that the authors concur with the Critical period hypothesis. Nevertheless, even within this critical period hypothesis, given that childhood can be presented as a spectrum, Wang et al. (2022) conclude that age increases language ability. As posed by Hartshorne, Tenenbaum, and Pinker (2018), this ability reaches its peak at the age of 25 years, after which it begins to taper off.  

            Other researchers have also established progressive development in language abilities within childhood cohorts, as concluded by Wang et al. (2022). For instance, Gilligan-Lee et al. (2021) concluded that spatial language skills show progression between 6 and 10 years, indicating that an increase in age within the confines of the childhood stage of human development results in an increase in language ability. The cross-sectional study by Gilligan-Lee and colleagues involved 155 children. They utilized regression analysis to establish relations between spatial language and performance on spatial tasks and the relation between different mathematics skills and spatial language. In both cases, there was a significantly positive correlation showing that an increase enhances language ability.

            The three articles discussed so far elicit two critical points. Firstly, they show the Critical period theory, and secondly, they show that language ability increases with age in youthful years. These findings are consistent with neuroplasticity, where this development period experiences dramatic brain growth and development. This means that the areas of the brain that support language abilities also develop progressively in this period. Some studies have taken this view and aimed to establish how different areas of brain development, visa-a-vis language ability, can explain why children have better language ability. In this regard, Olulade et al. (2020) argued that two types of evidence suggest contradictory pictures of how language is represented in the brain during development. In the first instance, anatomical, physiological, and fMRI activation studies show that, at birth, language is lateralized to the left hemisphere (LH). In contrast, damage to both or either the LH or RH can equally impair language development (Olulade et al., 2020), suggesting that language is bilaterally represented in the brain. Thus, the researchers aimed to solve this contradiction by examining fMRI language activation in different approaches. A key finding, notwithstanding outcomes on the actual representation of language on the brain, was that children systematically show RH language activation that declines with age.

            The problem with this outcome is that there is no explanation for whether the systematic decline of RH language activation implies the LH takes over the language tasks or whether the decline amounts to the reduction of language ability. Further, this outcome appears to contradict findings by Wang et al. (2022), Hartshorne, Tenenbaum, and Pinker (2018), and Gilligan-Lee et al. (2021), where it was established that language ability depends on the Critical period hypothesis and increases with age in the youthful developmental stages. Here, Olulade, Seydell-Greenwald, and Chambers (2020) suggest that the youngest children have better brain function for language ability and that this function declines with age. This study was an iteration of earlier and similar research.

In the earlier research, Olulade et al. (2020) compared children (4 – 13 years) and adults (18 -29). Outcomes from this study indicated that both the LH and RH form part of the language network in the brain. However, the RH activation appears to fade with age, leading to adults who rely primarily on the LH. In this case, the authors attempted to explain that children show an inclination to both LH ...