Basal Cognition

In plain language

Basal cognition asks what remains of cognition when we set brains and nervous systems aside. A cell can detect differences, compare present conditions with recent history, change its internal state, and select among costly actions. The term gives us a way to study those capacities without assuming either human-like thought or machine-like passivity.

Why it matters

Calling a response “cognitive” is useful only when it generates sharper experiments. It encourages questions about information, memory, alternatives, and error: What did the organism have access to? Which past events changed its response? What other action could it have taken? Under what environmental structure does its strategy improve fitness?

In my work

I use controlled environments and quantitative models to test these questions in unicellular systems, especially Capsaspora owczarzaki. The aim is not to decide whether a cell “thinks,” but to identify the smallest experimentally defensible components of sensing, learning, and decision-making.

Key examples

• Chemotaxis, where a cell compares conditions across time rather than reading a single concentration.
• Stress preparation, where one cue changes a later response to another condition.
• State-dependent decisions, where identical environments produce different actions because cells carry different histories.

Further reading

• Knafo, Casacuberta & Ruiz-Trillo (2026), Beyond Diffusion: Bayesian Learning Strategies in Single-Cell Life.