What term describes mental responses that cannot be directly measured?

The term that describes mental responses that cannot be directly measured is "mental responses." This term encompasses the internal processes and activities of the mind, such as thoughts, feelings, and perceptions, which are often inferred from behavior rather than directly observed.

Cognitive psychology focuses on understanding how mental processes influence behavior, but unlike observable physical actions or behaviors, mental responses rely on subjective experiences that are not quantifiable. For example, while one can measure how quickly someone reacts to a stimulus or how accurately they perform a task, the underlying processes of thinking and perception are more abstract and cannot be directly seen or measured.

In the context of the other options, behavioral responses refer to observable actions that can be measured (like responses in a behavior experiment), and physical responses specifically pertain to physiological reactions such as heart rate or muscle tension. The term "cognitive intervals" is not a standard term in cognitive psychology and may be a misunderstanding or misapplication of concepts related to cognitive processes. Thus, "mental responses" is the correct terminology to encapsulate these intangible mental activities.