Modern researchers have critiqued Piaget's theory of cognitive development on several fronts. One major critique is the underestimation of children's cognitive abilities in the early stages. Research has shown that infants and young children possess more advanced cognitive skills than Piaget recognized, particularly in terms of their understanding of object permanence and their ability to engage in complex reasoning. Additionally, critics argue that Piaget's theory overemphasizes the role of age and stages, suggesting that cognitive development is more fluid and continuous than his stage-based model implies. There is also criticism regarding the lack of emphasis on the social and cultural context of development. Piaget's theory primarily focuses on individual cognitive growth, while subsequent theories, such as Vygotsky's, highlight the importance of social interaction and cultural tools in cognitive development. Furthermore, some researchers point to Piaget's research methods, which relied heavily on observational studies of his own children, as lacking generalizability to a broader population. Despite these critiques, Piaget's theory remains foundational, with modern research building upon and refining his insights into cognitive development.

The information processing theory explains cognitive development through the lens of how children encode, store, and retrieve information, offering a more detailed look at the cognitive processes involved in learning and memory than Piaget's theory. While Piaget's theory outlines stages of cognitive development, with each stage representing a qualitative change in thinking and understanding, the information processing theory views cognitive development as a series of gradual, quantitative improvements in the efficiency and capacity of memory systems, attention, and problem-solving skills. This theory likens the mind to a computer, focusing on the mechanics of how information is processed, rather than the stages through which an individual progresses. It suggests that improvements in cognitive development can be attributed to increases in processing speed, working memory capacity, and the use of more sophisticated strategies for learning and remembering information. For instance, as children grow, they become better at using mnemonic devices, chunking information, and employing metacognitive strategies to enhance their learning and recall. In contrast to Piaget's stage-based approach, the information processing theory provides a framework for understanding the continuous and incremental improvements in cognitive functions that underpin learning and memory throughout childhood and beyond.

In Piaget's theory, language development is seen as both a reflection and a tool of cognitive development. Piaget believed that cognitive development precedes language development, with advances in thinking enabling the progression of language skills. He viewed language as a manifestation of cognitive ability that evolves as a child moves through the stages of cognitive development, particularly becoming crucial in the preoperational stage where symbolic thought emerges. Language, in Piaget's view, is vital for the development of logical thinking and reasoning, especially in the concrete operational and formal operational stages.

Conversely, the information processing theory posits that language development is crucial for cognitive development because it enhances the child's ability to process, store, and retrieve information. From this perspective, language is a critical tool that supports and facilitates memory, attention, and problem-solving processes. It helps in the organization of thoughts, the encoding of information into memory, and the development of metacognitive strategies. Language allows for the internal dialogue that is essential for thinking through problems, planning, and self-regulation. Thus, while Piaget's theory emphasizes the role of cognitive development in driving language skills, the information processing theory highlights the integral role of language in enhancing and supporting cognitive processes, making it a central component in the development of learning and memory capabilities.

Schemas are fundamental building blocks of cognitive development according to Jean Piaget. They are cognitive structures or frameworks that help individuals organize and interpret information from the world around them. In children, schemas evolve through two key processes: assimilation and accommodation. Assimilation occurs when new information is incorporated into existing schemas, while accommodation involves modifying existing schemas or creating new ones in response to new information that does not fit into previously held schemas. This dynamic process allows children to adapt to their environment intellectually. For example, a child might have a schema for dogs based on their pet. When they encounter a cat for the first time, they might initially assimilate this new animal into their existing dog schema. Upon realizing the differences, they accommodate their understanding by adjusting the schema to include new categories for both dogs and cats. This process of building and adjusting schemas is crucial for cognitive development, as it enables children to construct a more complex and nuanced understanding of the world.

The development of theory of mind is an important aspect of cognitive development that intersects with Piaget's stages, particularly during the preoperational and concrete operational stages. Theory of mind refers to the ability to understand that other people have their own thoughts, beliefs, desires, and perspectives that are different from one's own. This capability starts to emerge towards the end of the preoperational stage and becomes more refined during the concrete operational stage. In Piagetian terms, the development of theory of mind is a clear indication of moving away from egocentric thinking (characteristic of the preoperational stage) towards a more objective understanding of the world, where children recognize that their thoughts and feelings are not necessarily shared by others. This cognitive leap is crucial for social interaction and communication, as it underpins the ability to empathize with others, predict their behavior, and engage in complex social relationships. The maturation of this skill reflects the broader cognitive advancements that occur as children transition through Piaget's stages, showcasing the integration of social cognition into the framework of cognitive development.