Final answer:
Samuel Carver is not an early contributor to behavioral neuroscience, unlike Wilhelm Wundt, William James, and Rene Descartes, who have made significant contributions to the field's early development.
Step-by-step explanation:
To answer which one among Wilhelm Wundt, Samuel Carver, William James, and Rene Descartes is not an early contributor to behavioral neuroscience, we need to look at their contributions to psychology and related sciences. Wilhelm Wundt, known as one of the founders of psychology, created the first laboratory dedicated to psychological research, employing introspection to understand conscious experiences. William James, often referred to as the father of psychology in the United States, was a proponent of functionalism, incorporating both introspection and objective measures in his studies. Rene Descartes, the 17th-century philosopher, made significant contributions to the understanding of the mind-body relationship that impacted later psychological theories. In contrast, Samuel Carver does not appear in historical records as an early contributor to the field of behavioral neuroscience or psychology. Therefore, Samuel Carver is the correct answer as the one who is not an early contributor to behavioral neuroscience.