A receptive field refers to the specific area of sensory space in which a stimulus will trigger the firing of a neuron. In the context of the visual system, for example, a receptive field can be the portion of the visual field that influences the activity of a particular retinal ganglion cell. Each neuron has a unique receptive field, which helps the brain process and interpret sensory information. Receptive fields are crucial in various sensory systems, including auditory and somatosensory pathways. They help determine how sensory information is organized and perceived, allowing organisms to respond effectively to their environment. Understanding receptive fields is essential in fields like neuroscience and psychology, as they provide insights into how the brain processes complex stimuli.