Question

Infants younger than six months who have normal hearing can readily distinguish between acoustically similar sounds that are used as part of any language not only those used in the language spoken by the people who raise them. Young adults can readily distinguish between such sounds only in languages that they regularly use. It is known that the physiological capacity to hear begins to deteriorate after infancy. So the observed difference in the abilities of infants and young adults to distinguish between acoustically similar speech sounds must be the result of the physiological deterioration of hearing. The reasoning in the argument is flawed because the argument (A) sets an arbitrary cutoff point of six months for the age below which infants are able to distinguish acoustically similar speech sounds (B) does not explain the procedures used to measure the abilities of two very different populations (C) ignores the fact that certain types of speech sounds occur in almost all languages (D) assumes that what is true of a group of people taken collectively is also true of any individual within that group (E) takes a factor that might contribute to an explanation of the observed difference as a sufficient explanation for that difference

Short answer

(E) takes a factor that might contribute to an explanation of the observed difference as a sufficient explanation for that difference

Step-by-step solution

Understand the Argument

The argument claims that infants can distinguish between acoustically similar sounds from any language, while adults can do so only for regularly used languages. It attributes this difference to the deterioration of hearing abilities after infancy.

Identify the Conclusion

The conclusion drawn in the argument is that the difference in ability between infants and adults is due to physiological hearing deterioration.

Examine the Flaw

The flaw here involves the assumption that hearing deterioration is the sole explanation for the observed difference in sound discrimination abilities between infants and adults.

Analyze the Options

Evaluate each option to determine which one identifies the flaw. Options (A) and (B) are about arbitrary cutoffs and methodology, which aren't relevant to the main logical issue. Option (C) is incorrect because commonality of some sounds does not address the flawed causal claim. Option (D) concerns generalization on an individual basis, unrelated to the argument's main logical error. Option (E) correctly identifies the flaw: mistaking a potential contributing factor (hearing deterioration) for a complete explanation.

Key concepts

Sound Discrimination

Sound discrimination refers to the ability to distinguish between different sounds, even if they are very similar. This skill is essential for language development, as it helps in understanding and producing sounds correctly.
Infants have a remarkable ability to recognize subtle differences in sound. This is not confined to a single language but extends to all human languages.
Their ability to perceive these nuances is at its peak at this young age, which is crucial for language acquisition as they grow. Sound discrimination in infants is exceptionally high because they can discern between phonetic differences that they might never encounter in the language spoken around them. As they grow older, especially if exposed to only one or a few languages, they lose some of this ability, focusing more on the sounds relevant to their language environment.
Hence, infants are like linguistic sponges, ready to absorb a wide range of phonetic sounds from around the world.

Infant Learning

Infant learning is a critical phase where humans are exceptionally receptive to new information. During this period, infants learn primarily through observation and experimentation, often without explicit instruction.
They are adept at picking up patterns from their environment, and this includes the sounds they hear.
Their brains are wired to capture phonetic variations, which helps them in distinguishing similar sounds. The first year of life is when significant cognitive growth occurs. Babies learn not only the sounds of their native language but also recognize differences in other languages. This wide-ranging ability provides the foundation for future language skills.
As they interact with caregivers and their environment, infants continuously refine their sound discrimination abilities, setting the stage for language development and cognition.

Hearing Deterioration

Hearing deterioration typically begins subtly after infancy. This natural process involves a gradual decrease in auditory capacity, impacting the ability to distinguish between sounds over time. Although it starts early, noticeable effects on sound discrimination may become evident later in life.
This decline is a normal part of aging, affecting everyone to some degree. In the argument, hearing deterioration is presented as the main reason for the difference in sound discrimination abilities between infants and adults. However, this overlooks other factors, such as the focus adults place on the languages they regularly use, which plays a significant role.
While it's true that physiological changes contribute to decreased auditory capacity, it's important to consider how language exposure and usage can shape listening capabilities.

Argument Analysis

Argument analysis involves examining the structure of a logical statement to assess its validity. In this context, analyzing the argument helps understand the reasoning behind the claim that hearing deterioration is the sole factor in sound discrimination ability differences. The flaw in the argument lies in attributing the entirety of sound discrimination differences to hearing deterioration.
While this is part of the explanation, it is not sufficient alone. Factors such as language exposure and the brain's adaptation to commonly used sounds play significant roles. Identifying that the reasoning overlooks these factors, and instead makes a hasty generalization, is crucial.
Successful argument analysis identifies weak points, like the mistaken belief that hearing deterioration is the only cause, enabling more informed interpretations of complex issues.