A scheme for recognizing speech represented by a sequence of frames of acoustic events separated by boundaries, according to which the frames of speech are processed to assign to received frames respective boundary probabilities representative of the degree to which the frames of speech correspond to stored representations of boundaries between acoustic events. The assigned boundary probabilities are used in subsequent processing steps to enhance recognition of speech. The assignment of boundary probabilities and further adjustments of the assigned probabilities are preferably conducted by an artificial neural network (ANN).