Studies on ambiguity suggest that chunking is time-constrained. Neuroscientific work suggests that the brain processes information in discrete time windows provided by electrophysiological cycles. We found cycles in the order of seconds to affect ambiguity resolution, and thus chunking. Cycles, duration-confined by anatomical principles, may be a neural chunking bottleneck.
Psycholinguistic research suggests a time limit on the chunking of words—listeners do not appreciate long chunks. For instance, in the ambiguous sentence “The client sued the murderer with the corrupt lawyer.”, a lengthening of “the murderer” by means of additional words would bias listeners to split off the subsequent prepositional phrase “with the corrupt lawyer” and interpret it as an instrumental argument of the verb “sued”. In recent years, neuroscience has shown that the brain processes information in discrete time windows provided by cyclic alternations of electrophysiological activity. Thereby, every electrophysiological cycle is a processing time window; listeners perceive all information that falls into a single cycle as a single unit. Importantly, the duration of such cycles is confined to specific ranges, governed by anatomical principles. I will present here results from neurolinguistic experiments employing electroencephalography and neurostimulation, focusing on attachment ambiguities and garden-path sentences. We found evidence that electrophysiological cycles in the order of seconds affect syntactic ambiguity resolution, thus constraining the grouping of words into chunks. Specifically, our results support the simplistic claim that listeners terminate a chunk whenever they approach the end of an electrophysiological processing cycle. We thus propose that electrophysiological cycles are a neural bottleneck on online chunking. We currently investigate whether individual differences in cycle duration may explain interindividual variance in chunking preferences. Furthermore, in the future, we will employ computational-linguistic methods to assess whether the anatomically constrained duration of electrophysiological cycles is a neuroscientific explanation for cross-linguistic consistency in chunk duration.
