Sequence representation as an early step in the evolution of language
Fig 5
Performance of Flexible Sequence, Depth-4 and Trace representations, in environments with varying proportions of sequentially structured information.
For the Flexible Sequence and Depth-4 representations ℓ = 4. For the trace representation θ = 1/2. The probability of encountering information in sequences is determined by p in each environment. Sequential information is contained in the two sequences (A, B) and (B, A) that are equally distributed over the three time steps where they fit. All other information is in single stimuli and is equally distributed over the four time steps. The x-axis represents the time-steps or learning opportunities and the y-axis represents the performance measured after a given number of time-steps, as described in the methods section. a: Learning in an environment where information is encountered in sequences with p = 0 and all information thus is in single stimuli. b: Learning in an environment where information is encountered in sequences with p = 0.25. c: Learning in an environment where information is encountered in sequences with p = 0.5. d: Learning in an environment where information is encountered in sequences with p = 0.75. e: Learning in an environment where all information is encountered in sequences.