Defining levels of joint attention is important in determining if children are engaging in age-appropriate joint attention. There are three levels of joint attention: triadic, dyadic, and shared gaze.
Triadic joint attention is the highest level of joint attention and involves two individuals looking at an object.[2] Each individual must understand that the other individual is looking at the same object and realize that there is an element of shared attention.[3] For an instance of social engagement to count as triadic joint attention it requires at least two individuals attending to an object or focusing their attention on each other.[4] Additionally, the individual must display awareness that focus is shared between himself or herself and another individual.[4] Triadic attention is marked by the individual looking back to the other individual after looking at the object.
Dyadic joint attention is a conversation-like behavior that individuals engage in. This is especially true for human adults and infants, who engage in this behavior starting at two months of age.[2] Adults and infants take turns exchanging facial expressions, noises, and in the case of the adult, speech. Sensitivity to dyadic orientation plays a major role in the development of dyadic attention.[5] Infants must be able to correctly orient towards in response to the attention seeking interaction.
Shared gaze occurs when two individuals are simply looking at an object.[6] Shared gaze is the lowest level of joint attention. Evidence has demonstrated the adaptive value of shared gaze; it allows quicker completion of various group effort related tasks[7] It is likely an important evolved trait allowing for individuals to communicate in simple and directed manner. It has been argued that shared gaze is one of the main precursors to theory of mind.[8]
Individuals who engage in triadic joint attention must understand both gaze and intention to establish common reference. Gaze refers to a child's understanding of the link between mental activity and the physical act of seeing. Intention refers to the child's ability to understand the goal of another person's mental processes.
