Is there a difference between physiological stimulations and psychological stimulations?

Question

From what I understand, physiological stimulation (or stimulus or sensation) "refers to sensory excitation, the action of various agents or forms of energy (stimuli) on receptors that generate impulses that travel through nerves to the brain (afferents)", while psychological stimulation (or conceptualized stimulation) involves cognitive process like perception, reasoning, emotion, experience. However, reading the Wikipedia page of stimulation, I feel like the two concepts are the same.

Are they the same or different? I guess we can say that psychological stimulation is physiological stimulation because it can explain (or be explained by) these phenomenons:

• Brainwaves are combinations of harmonic oscillators range from 0.5 to 700 Hz
• Synesthesia, when some people can literally see an orange triangle in space when they hear a trumpet

If so, how does this energy change in the brain related with perception, reasoning, emotion, experience? Is there any experiment that support or against this?

_{FYI: Physically, when the oscillators aren't aligned, the wave will not jump:}

_{But if they are aligned, the wave will jump:}

^{Related:
• Does neurodynamics have any relation to psychodynamics?
• Why do brains oscillate within specific frequency ranges?
• Is there a relation between large-scale oscillations and small-scale oscillations? in Physics}

Answer 1

Psychology and physiology are at different levels of explanation or levels of analysis. The answer depends entirely on how you view the relationship between such levels and in particular (mental) causality within and between levels. As this is still heavily debated, this metaphysical consideration is a precursor for giving a more specific answer to your question. Some options:

The physicalist and reductionist answer is probably the simplest: they are the same thing, only physical stimulation is the only real one! According to this view, Psychology is an (epiphenomenal) abstraction which is entirely realized by lower levels. Therefore, there can only be psychological stimulation in the presence of physical stimulation, but the latter may occur without the former being intrinsic to that. As an example, you present a snake to the subject to elicit psychological fear, but the physical stimulation (photons tranduced by the retina and the pressure transduced by the cutaneous receptors in the skin) is a necessity for this to happen. If you count neuronal activity as physical self-stimulation, then fearful memories could be cast in the same language.

Others try to keep the relationship between levels less well defined. For example, if you align more with emergentism, poetic naturalism, or the like, you acknowledge the underlying physical reality, but you want to keep the causal language such as "the snake made him fearful" within a given level of analysis rather than crossing levels. So the answer to your question is that there IS no difference, but you better act as if there is because you'll miss something or get confused if you don't.

A dualist, of course, would hold that physical stimulation and psychological stimulation can (at list in principle) occur in its own right. Usually, they have great difficulties answering the very question you pose, and even though most people in their day-to-day lives tend to think dualistically (as intuitive psychologists), very few defend dualism in academia nowadays.

There are other positions as well, and each of the above has many branches. But the above should give some search terms to get acquainted with the heavy players in the field.