What parts of our bodies do we rely upon when gathering empirical evidence?

Empirical evidence, also known as sense experience, is the knowledge or source of knowledge acquired by means of the senses, particularly by observation and experimentation.

We rely upon all parts of our bodies when gathering empirical evidence but we mostly rely on our brains to process the information that becomes the empirical evidence. To be more specific, we use our nervous system which is divided into central nervous system (brain, spinal cord) and the peripheral nervous system (mainly consists pf nerves) which are long fibres or axons that connect CNS to all parts of the body.