Neuro Garden — Drawn by a Plant's Bioelectric Potential

From an unseen flicker, we picture a form

In Neuro Garden (Pachypodium densiflorum ver.), the living bioelectric potential of a Pachypodium densiflorum is read in real time, and its subtle changes are drawn as a line by a plotter. This potential is the plant's own nervous signal, faint and forever trembling. Fed by it, branches reach for points in space and divide — imagining another densiflorum's form, drawn by its potential.

Light, temperature, moisture, the presence of people: a plant responds to countless stimuli every day, expressing its state as faint electrical signals. Each drawing records the time the plant spent in this space — a one-day record whose lines will never appear again.

How it works

Electrodes are attached to a potted Pachypodium densiflorum, and a microcontroller (Arduino) measures its bioelectric potential about once per second
The skeleton of the caudex plant is generated by 3D Space Colonization: branches grow toward "nutrient points" scattered in space, absorbing nearby points as they divide. Branch thickness follows the pipe model (the sum of cross-sections is preserved)
The skeleton is projected in parallel and converted into the caudex outline, growth rings, and wood-grain lines
While drawing, the difference between the latest potential and the baseline (the average at the start) is added as an offset along the normal of each grain line. The trembling of the line is the fluctuation of the plant's potential itself
A pen plotter (AxiDraw) draws on A4 paper over about four hours. During the exhibition, a new drawing was made every day