Cognitive sequence processing and syntactic comprehension in schizophrenia

Abstract

It has been repeatedly demonstrated that schizophrenic patients are impaired in the comprehension of sentences with complex syntax. We investigated the hypothesis that this syntactic comprehension impairment in schizophrenia is not a purely linguistic dysfunction, but rather the reflection of a cognitive sequence processing impairment that is revealed as task complexity increases. We tested 10 schizophrenic patients using a standard measure of syntactic comprehension, and a non-linguistic sequence processing task, both of which required simple and complex transformation processing. Patients' performance impairment on the two tasks was highly correlated (r2 = 0.84), and there was a significant effect for complexity, independent of the task. These results are quite similar to those of aphasic patients with left hemisphere lesions. This suggests that syntactic comprehension deficits in schizophrenia reveal the dysfunction of cognitive sequence processing mechanisms that can be expressed both in linguistic and non-linguistic sequence tasks.

A Neurolinguistic Model of Grammatical Construction Processing

“…The first test of this prediction was thus to compare performance in aphasic patients on these two types of behavior. We observed a highly significant correlation between performance on syntactic comprehension and abstract structure processing in aphasic patients, as well as in schizophrenic patients Lelekov et al, 2000). We reasoned that if this correlation was due to a shared brain mechanism, then training in one of the tasks should transfer to improvement on the other.…”

Sentence Comprehension and Its Association with Executive Functions in Patients with Parkinson's Disease

“…Finally, cognitive sequencing was evaluated with a protocol based on Lelekov et al [47] (see also [48] for a detailed description of the test adapted for Dutch). The aim of the task was to assess the ability to learn letter-sequences with a complex abstract structure (e.g., A-B-C-B-A-C) in order to judge whether a given letter sequence followed the pattern or not.…”

Emergence of grammatical constructions: evidence from simulation and grounded agent experiments

“…The transformation processing will continue to be associated with activation of pars opercularis Ba44, but not with activation of pars triangularis Ba45. demonstrated correlated impairments in their ability to process the abstract structure of nonlinguistic sequences (Lelekov et al 2000. According to this model, the correlation derives from the common functional system that performs both tasks (Dominey 2002).…”

“…Neural activity in large populations of neurons that are aligned in the cortical surface generates electrical dipoles that can be measured with surface electrodes placed in contact with the scalp. Using this technique for measuring brain activity, we first demonstrated that the processing of simple serial structure versus abstract rule structure relied on dissociable neural processes, with abstract structure violations resulting in a P600 response similar to that seen in syntactic structure violations, which was absent in the case of simple serial order violations (Lelekov et al 2000). Subsequently, a task was devised in which the choice of the abstract structure to apply was guided by the presence of a special 'function' symbol, analogous to function words in language.…”