Neural receptive fields map the spatial or temporal distribution of the data to
ID: 32427 • Letter: N
Question
Neural receptive fields map the spatial or temporal distribution of the data to individual neuron excitation, if I understand correctly, but I do not understand if receptive fields (especially in the higher cognitive areas such as the various layers of the visual cortex, etc.) are:
Actual structural distributions of neurons that help map specific spatial or temporal properties of stimuli (such as concentric arrangement for contrast detection, rectangular arrangement for orientation detection, or movement detection, etc.), or,
Merely a mapping of the structure of the stimuli that can excite specific neurons.
If it's the latter, isn't it basically as simple as a pattern/feature/vector that individual neurons are sensitive to?
Explanation / Answer
No, it is not 1. the structural distribution of the neurons themselves. If by mapping you mean a kind of function that maps real space to cognitive space (or such) then it is not that either (at least, not explicitly/directly).
The receptive field is the region of 3D space in which sensory neurons can make their relevant detection. It's not a pattern/feature/vector, just the coordinates defining some spatial region itself.
For example, take the neurons making up your audio sensory system. If an object is making noise and you can hear it, then that object is within the receptive field of the hair cells responsible for the audible frequencies. That is, the object's physical location is within the spatial coordinates that define your audio system's perceptive field.
Fun fact: for two sounds of the same amplitude, lower frequency detecting hair cells tend to have a larger receptive field since lower frequency signals travel farther. In other words, the receptive field is somewhat dependent on the quality of the source of perception, not just the sensory neurons.
It's strange terminology coming from physics, because we generally define "fields" by sources, not by receivers. An audio source has an unambiguous "field" of acoustic radiation. A receiver does not generate a field but is sensitive to a certain threshold of field quantity. So to define the field as something coming from the receivers (the sensory neurons) is an unintuitive idea.