Is matching innate?
Matching can show up on day one with no teaching—species and procedure decide if it is innate or learned.
01Research in Context
What this study did
Watson et al. (2007) watched mice choose between two levers that gave food at different rates.
The animals had never been trained before.
The team simply counted how long the mice stayed on each lever as the payoff rates changed.
What they found
The mice split their time on the levers in the same ratio as the food they got.
No teaching, shaping, or reinforcement history was needed.
Sudden jumps in payoff caused quick, matching shifts in where they stayed.
How this fits with other research
Burack et al. (2004) saw the opposite with pigeons.
Those birds only started to match after they learned to hop between keys.
The clash is simple: mice match without practice, pigeons need it.
Species and task differences likely explain the split.
Sanders et al. (1989) also failed to find abstract matching in monkeys, again showing that matching rules do not hold across every setup or animal.
Why it matters
If matching can appear without training, you cannot assume every client who shows it was taught that pattern.
When you see a child split time across two tasks in perfect proportion to rewards, ask: is this learned or built-in?
Use baseline probes before you teach switching skills; the tendency may already be there and you can build on it instead of starting from zero.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Run a five-minute free-choice probe between two reinforcers and see if the split already mirrors the payoff rate before you train any switching.
02At a glance
03Original abstract
Experimentally naive mice matched the proportions of their temporal investments (visit durations) in two feeding hoppers to the proportions of the food income (pellets per unit session time) derived from them in three experiments that varied the coupling between the behavioral investment and food income, from no coupling to strict coupling. Matching was observed from the outset; it did not improve with training. When the numbers of pellets received were proportional to time invested, investment was unstable, swinging abruptly from sustained, almost complete investment in one hopper, to sustained, almost complete investment in the other-in the absence of appropriate local fluctuations in returns (pellets obtained per time invested). The abruptness of the swings strongly constrains possible models. We suggest that matching reflects an innate (unconditioned) program that matches the ratio of expected visit durations to the ratio between the current estimates of expected incomes. A model that processes the income stream looking for changes in the income and generates discontinuous income estimates when a change is detected is shown to account for salient features of the data.
Journal of the experimental analysis of behavior, 2007 · doi:10.1901/jeab.2007.92-05