Lets break down the components.
physiology, metabolism, emotions and spatial versus logical part of the brain hemispheres.

Physiology, we need to introduce some physics with collagen protiens interactions with water in our connective tissue. Collagen is piezoelectric liquid crystal. Technically it is piezo-protonic. (read articles in my writings (citations to peer reviewed journals) Collagen confluences and planes match with acupuncture meridians. Needle grasp of acupuncture needles function from mechanical activation of confluence of collagen fibers and due to strong electron bonds between the protien and hydrogen atoms of the water molecule, the hydrogen nucleus ( a proton) moves up the chain to the next water molecule. This moves mass and charge. The charge is enough to encourage ionic exchanges of calcium, sodium and chlorine channels in cells and affect metabolisms. This metabolic change encourages kinesthetic senses, feelings that is translated into symbolic language in the left brain where symbolic labels are assigned. The right brain is more spatial and does pattern matching. Feelings launch pattern enervation of the brain, encourage specific analytical processes of those regions that have been previous programmed and elicit from that emotional pattern memories. Imagine a solid state referencing engine taking snapshots of data in flow between OS implementations in hibernation to the next OS implementation out of hibernation with a program. Most people actually think from a personality or a flow of emotional conceptual paradigms linking sections of thought. People feel comfortable if the emotional changes matches tempo, rhythm and expected pre-programmed responses.

Non-magical people expect their paradigms to function in given patterns with given metabolisms and emotions where they feel comfortable.
The fuzzy thinking of these people's magical thinking versus that of actuall magicians. Normal people if they have a successful acquisition of things, by playing along this stream of emotional paradigms illiciting thoughts in a pattern that they feel comfortable, the actual thinking of patterns and cause and effect is not used. It is a response pattern that they are comfortable with.

Mystics take a look at the inner landscape, with a much wider sets of patterns of emotions, events stimuli and world view stimuli and label experiences to manage them. Here the socio-psycological inculturation of traditions, and rituals make sense to the practitioners who have common frames of references and experiences to share with others who have been initiated in like and similar experiences using their common language.

Lets get back to the physiology. People can ennervate their body charging their body by emotions, which stimulate metabolism changes and thereby changing the charges along the collagen piezo-protonic pathways. This charge can create EMF at low frequencies, oriented along the fibers. Posture, movement, chanting and rythmic movements, co-identified with magickal practices can stimulate these proton changes through the physical compression of the collagen fibers. So there is sound, movement and ritual that can create EMF changes in a pattern. The body can pickup on the EMF from the environment and creates kinesthetic and other physical sensations, along with co-relevant metabolism changes that the mind interprets and if practices gives it symbolic referencing. Notices this is not a direct, nerve stimuli experience. These are interpreted responses from the body.

Direct nerve sensing can come from pressure changes in muscles (specific nerve endings) can detect pressure changes. The muscles in their long cells through contraction can stack water in laminar stacking. This can make specific EMF absorption, emissions detectable in very specific orientations.

Isaac Bonewitz's book, made references to Reich's ( i believe) work that showed higher percentages of ESP perceptions at initially upto 15 M and a second level results to 1500M. He defined these alpha and beta levels of psychic activity. Physicists have described electro-weak phenomena to have a similar set of limits. This is another correspondence that deserves close analysis. This also makes sense between the energy exchanges that would be centered around and closer to either end of the spectrums of EMF and Weak Nuclear forces. The orientation of materials is the only thing that has not been described due to being a physical limitation in material sciences that would smooth out the spectrum of experiences and observed interactions for these forces. The observed forces tend to be more erratic and lack enough coherent observations to illicit a useful exploration and illiciting of research moneys.

The funny thing of moving protons versus electrons, you can't measure it with standard electrical devices that are designed to measure flow of electrons. The other odd thing is the whole spectrum of electro-weak phenomena the energies between Electro-magnetic and Weak Nuclear forces. Londons and Vanderwalls forces, along with Lambs and Kasimir effects are noted phenomena in these spectrums of nuclear forces.

The body and the collagen fibers can generate patterns of these types of energy. And at some level we can receive and interpret this energy reflecting or coming off from the world around us. These frequencies are anywhere from 3 to several thousand HZ. Odd enough that these are if turned into sound would be audible. Second source of EMF from the body is micro tubules in the brain giving off signals in the megahertz ranges. ( a side note, I haven't linked that with specific phenomena and the study of Taoist chi gong in the terms of chi and yi, may be a set of overtone relationships.)

The symbolic relationship of

magick circles
Given a pattern of containment, standing waves, and development of the immediate environment with a pattern of energy.
Okay My further conjecture is that if studied well enough of the electro-weak phenomena and charge and parity paring, that the Heisenberg principle is an observed effect of hadrons and leptons (protons/neutrons and electrons) phasing out of time (observable world due to the speed of light) and causing a flux in these energy that acts as a particle, where one day the discovery of the conservation of time will be needed to understand the relationship dynamics and geometry picking up with particles that match the midpoint of the time phase.)
This makes sense in Swedenborg/spiritualist sense of protoplasm and the Chinese understanding of Yin Chi or Shen that coherence can be messed up with external EMF sources such as light. (conjecture)

complicated rituals
Given the physical behavior and the linked Emotional-mental-conceptual-constructs and the pattern of energies, behaviors, from overlaid emotions and metabolistic patterns, it is a learned and taught methodology from these complicated imperical experiences.

the use of herbs, stones, wands, cloaks, and other items
to complicated. Stones, wood, objects all depend on the patterns of energy that they absorb, emit or can extend as a tool of the operator.
Cloaks, candles, or other tools, can be either energetic or mnemonic queue to set up the mind, that sets the metabolism and complex patterns in the brain and in the body.
Individual items hold a mental queue of patterns, creating micro-disassociative states in the mind to overlay complex patterns over and over again.
Psychic healers, have been observed to have (if I remember correctly) their delta brain waves go from 10 HZ to 40 HZ when manipulating energy. This would create a higher resonance of patterns from a persons body.

magick symbols/sigils
Again symbolic reference to queue the mind .... These have very deep metamagical thematic references very heavy laden with multiple layers of meaning. Not unlike the hebrew language in its esoteric studies in Kabbalah.
Some sigils methodologies infer type of energies and a pattern of energy where the operant duplicates.

shrines and alters
Altars A standard operating tool. A complex sets of mnemonics and imbued energetic patterns that is reinforced by the operant over time. complex patterns like relationships become a working dynamic. Statues etc,. pattern matching and queue illiciting to match with psychic patterns, forms and relationships, (gods or other entities)

stances and gestures
Queues and by the above exposition of imperical methods to generate energy.

use of the moon
The moon, like other YIN energy descriptions are when gravity, more likely pattern of masses of like material encourages a Higher flux of electro-weak activity. This flux of activity presents the operant a flux of energy, call it spirit, yin chi, prana etc, that less connected to the actual physical demesne of a set of materials. A demesne of physical materials are likely to keep the electro weak flux within it.
This makes it less necessary for the operant to disturb materials with their own energy to garner loose flux energies that are produced by nature.
Moon, Sun, trees, marshes (tri-phosphate breakdowns similar to ATP breakdown in the body), thermal inversions (water or air), fire, lighting, thunderstorms

Are some of these simply symbolic, a placebo effect to fool the mind to think something extraordinary is going to happen to access a spiritual connectivity with the universe?
Symbolic thinking is the gateway to interact with these forces, due to the lack of direct stimuli to the sense organs (except the eye- witch is linked to the brain and sense areas of the brain in a very symetric pattern, along with the eye is a sphere of (yes you guessed collagen fibers. Given and EMF relationship with the body, direct symmetric relationship as the optic nerve into the brain, and there are traditions of breathing energy through the eyes.
Meditation and breathing are tools to be aware of the energy and as it is in other yogas, are literal pumps of these piezo-protonic pathways to encourage a flow of energy, as charge or some quazi charge-mass that would definately interact in a electro-weak phenomena range.
Placebo effect, for many many practitioners who do not practice the actual energetic discipines of the various spiritual practices, it is a matter of belief. In the complex social psycology that creates a working dynamic in and social culture, behavior and conformity help create an imperical process where social and personal interchanges can be managed by gross cathartic measures to change interpersonal dynamics. I.e Gestalt and EST type of therepeutical practices. This requires the full commitment of the practitioner or patient.
There is quite a lot of anthropological studies given the actual operation of magic and the inherent and accepted social folkways to create scenarios that can precipitate these Gestalt experiences and accepted normative transitions to create the expected outcome, it should be obvious at least on the surface a work psycho-therapeutic practice. The emotional enhancements and shift in emotional patterns are need to transfer useful programming or behaviors in the the personality dynamic leaving the old in the unused modality. This is not unlike the underlying reality of 12 step practices, and weakly other cognitive therapy practices. Placebo effect is a deep psychological way to encourage the patient to enervate themselves in a mutually desired direction. It is not miraculous but psychological that has deep profound Gestalt interactions in a persons psyche that affects emotions, personality, and metabolism. The methods of tuning the mind and body in the psycho-therapy are just as anthropologically significant the life and times of the ages as each techniques has grown out of the social psychology of the era it was produced. The variant methodologies that exist today due to the imperical efficacy given a significant population. It being a soft science it too is an art of the psychologist to find a method and medium or one better suited for a different methodology to help their client.

Most of the magical practices are designed more to help individuals through their psychological changes in balance with society. The more esoteric practices of practioners deal with realm of all those things that can be experienced external to us. I.e. all this rich world of electro-weak phenomena and the beings, forms and denizen therein exist.

Forgive my wording, I am attempting to distill my years of research succinctly. This requires a full volume in the book I'm writing. And cross referencing it into actual magickal practices. I don't expect that any of this is sufficiently described. i am hoping that this is at a low enough level, where and if thoroughly groked, most of the spiritual practices will make more sense.