The core of this system is precise control of tonal frequencies linked to four independent color vision interfaces and an algorithm to generate a stepwise sequence that guarantees unpredictability.

The program assigns a unique frequency to each of the four buttons, which activate a sine wave oscillator at 415 hertz for green, 310 hertz for red, 252 hertz for yellow, and 209 hertz for blue.

This frequency setting has been carefully calculated to maximize the discriminability of musical scales in the human sense of hearing and to provide strong stimulation to the auditory cortex at the same time as visual lighting.

The random number generator determines the next sequence element according to a uniform distribution, and by adding new elements to the end of the existing array, it builds a list in which the amount of information to be memorized increases strictly by one at each turn.

This cumulative data structure serves to progressively push the boundaries of information held in working memory, causing a steady increase in cognitive load in proportion to the number of plays.

At the start of each turn, a process is run to play this array sequentially from the beginning, and by outputting visual and auditory stimuli with synchronized accuracy of milliseconds, a multisensory memory trace is etched into the player's brain.

As the player successfully reproduces the sequence and increases in level, the system intervenes with a dynamic difficulty adjustment mechanism that intentionally shortens the display interval.

The lighting and sounding time, which was secured at 1,000 milliseconds per element at the initial level, decreases according to a gradually decreasing function as it progresses, and eventually converges to the limit value of 300 milliseconds.

This tightening of time constraints gives rise to the phenomenon of rehearsal time deprivation in cognitive psychology, and is designed to make information retention in the phonological loop difficult.

Although the presentation time of 300 milliseconds is sufficient for encoding into visual short-term memory, it reduces the margin for conversion into verbal recitation, forcing the player to rely on pure sensory memory and intuitive spatial comprehension.

As the density of information presentation per hour increases, memory compression processing through chunking is inhibited, and the process in which the load index relative to working memory capacity rises in a sharp arc becomes observable as a mathematical transition model.

During the phase where the system waits for a response input from the user, the system monitors each physical or touch press of the button via an input event listener, and immediately compares the input information with the system's internal ground truth sequence with a pointer.

At this time, the moment the player presses the button, the exact same visual light oscillations and tonal output of a specific frequency as the system plays are synchronously fed back.

This allows players to perceive that their actions have been correctly recognized by the system, and at the same time experience integrated processing of motor output and sensory input.

The internal logic uses the array index to track the player's current position, and each time a button is pressed, it is rigorously matched against the value at that index in the correct answer array.

If a perfect match is confirmed, it advances the index by one and waits for the next input, but in the unlikely event that a mismatch is detected, the error handling process immediately fires, outputting an unpleasant low-frequency error sound and transitioning to a game over sequence.

This millisecond verification loop completes completely in the background without disrupting the tempo of the player's continuous input.

In order to completely eliminate communication delays with the server, this system completes all state management such as game progress, score calculation, and evaluation of user input history within the client-side memory of the browser.

By eliminating dependence on external databases, we have eliminated the possibility of fatal synchronization errors caused by network latency, even at high-level display speeds where display speeds are extremely short.

The maximum level reached, i.e. the longest number of elements in a memorized sequence, is immediately persisted via the local storage API upon completion of play.

This high score recording process is implemented with simple and robust logic that compares the previous best score with the current result and only overwrites the data block in storage if it is better.

At the start of the next session, this value is loaded as part of the startup sequence and presented on the interface as a past personal limit, creating a feedback loop that motivates players to continue challenging themselves.

The basic structure of Simon Says has the same memory capacity measurement function as the Digit Span Test, which is widely used in clinical psychology.

The level that the player finally reaches serves as a quantitative indicator of the short-term memory span at that point. For example, if a user fails at Level 9, it is interpreted that the user's visuospatial working memory has the capacity to hold eight independent pieces of information in sequence at the same time.

This system includes a framework that extracts the number of consecutive successes not simply as a game score, but as numerical data that indicates the width of the human information processing bottleneck.

The task of serializing and memorizing the multidimensional information of four color and sound combinations along the time axis and outputting them in exactly the same order rather than in reverse or random order is an extremely sophisticated cognitive task that requires the allocation of attention by the central executive system and the simultaneous operation of the phonological loop and visual-spatial sketchpad, and the degree to which this is achieved is a barometer for measuring the health of the brain's executive functions.

This system designed in this way goes beyond everyday entertainment and has practical value as a training tool for the prevention and rehabilitation of cognitive decline.

Using this tool regularly to challenge your memory limits stimulates synaptic plasticity and repeatedly strengthens your information encoding and retrieval networks.

In particular, the process of integrating visual flashes of light with graded acoustic stimulation ranging from 415 to 209 hertz stimulates the synchronized firing of neural networks across multiple areas of the brain, helping to form stronger memory traces.

A specification in which the presentation speed is shortened is an extremely effective source of stress for improving processing speed and training the ability to maintain attention, and brings out compensatory mechanisms in the brain that try to adapt to this.

As a result, the system is more than just a memory test device, but serves as a practical training platform that actively expands the user's short-term memory capacity through repeated use and maintains cognitive flexibility in daily life.