physarum IB-physarum-tube-memory

Physarum polycephalum encodes the location of a past nutrient stimulus in its tube-diameter hierarchy: tubes toward the food dilate and the diameter pattern persists after the stimulus itself is gone.

Observed quantities

imprint outlasts the consumed stimulus; carried by a softening agent (chemically unidentified; ATP candidate) advected on the Ca2+-driven shuttle-streaming flow

Primary source

Kramar & Alim 2021, PNAS

Boundary of this block

The softening/signaling agent is chemically UNIDENTIFIED and the memory READOUT is modeled, not directly measured; a published rebuttal disputes only the WORD 'memory', not the measured diameter imprint.

Connections

Outgoing

relates to A single ~5-minute trapping event teaches wild American crows a specific threatening human face: mask-specific scolding persists at least 2.7 years and SPREADS, rising from ~26% to ~66% of crows, while a neutral-mask control stays flat. controller-less memory that outlasts the stimulus that created it (Physarum tubes ~ crow faces)
relates to Physarum uses an EXTERNALIZED spatial memory — avoidance of its own extracellular slime trail — to escape a U-shaped trap: 96% of trials escaped (n=24) versus 33% when the whole arena was pre-coated with slime so the cue was uninformative. internal store (tube diameters) alongside an external store (slime trail) in the same organism

Incoming

relates from A single ~5-minute trapping event teaches wild American crows a specific threatening human face: mask-specific scolding persists at least 2.7 years and SPREADS, rising from ~26% to ~66% of crows, while a neutral-mask control stays flat. controller-less durable memory outlasting its stimulus by orders of magnitude
relates from Physarum uses an EXTERNALIZED spatial memory — avoidance of its own extracellular slime trail — to escape a U-shaped trap: 96% of trials escaped (n=24) versus 33% when the whole arena was pre-coated with slime so the cue was uninformative. external slime store operating alongside the internal tube-diameter store