F. Zwarts - Academia.edu (original) (raw)
Papers by F. Zwarts
Psychophysiology, 1999
Using positron emission tomography, visual presentation of sentences was shown to cause increased... more Using positron emission tomography, visual presentation of sentences was shown to cause increased regional cerebral blood flow relative to word lists in the left lateral anterior superior and middle temporal gyri, attributable to cognitive processes that occur during sentence comprehension in addition to those carried out during word comprehension. Additional comparisons showed that repeating words~in a different context, when subjects did not attempt to learn the initial lists! led to significant patterns of both increased blood flow~left putamen and right caudate! and decreased blood flow~left posterior temporal lobe!. Increases are argued to reflect retrieval of memory traces, whereas decreases reflect diminished necessity for processing of input. A decrease in the left inferior parietal lobe was attributable to other factors.
Brain and Language, 2004
In this paper we report the results of an experiment in which subjects read syntactically unambig... more In this paper we report the results of an experiment in which subjects read syntactically unambiguous and ambiguous sentences which were disambiguated after several words to the less likely possibility. Understanding such sentences involves building an initial structure, inhibiting the non-preferred structure, detecting that later input is incompatible with the initial structure, and reactivating the alternative structure. The ambiguous sentences activated four areas more than the unambiguous sentences. These areas are the left inferior frontal gyrus (IFG), the right basal ganglia (BG), the right posterior dorsal cerebellum (CB) and the left median superior frontal gyrus (SFG). The left IFG is normally activated when syntactic processing complexity is increased and probably supports that function in the current study as well. We discuss four hypotheses concerning how these areas may support comprehension of syntactically ambiguous sentences. (1) The left IFG, right CB and BG could support articulatory rehearsal used to support the processing of ambiguous sentences. This seems unlikely since the activation pattern associated with articulatory rehearsal in other studies is not similar to that seen here. (2) The CB acts as an error detector in motor processing. Error detection is important for recognizing that the wrong sentence structure has been chosen initially. (3) The BG acts to select and sequence movements in the motor domain and in cognitive domains may serve to inhibit competing and completed plans which is not unlike inhibiting the initially non-preferred structure or ''unchoosing'' the initial choice when incompatible syntactic input is received. (4) The left median SFG is relevant for the evaluation of plausibility. Evaluating the plausibility of the two possibilities provides an important basis for choosing between them. The notion of the use of domain general cognitive processes to support a linguistic process is in line with recent suggestions that the a given area may subserve a specific cognitive task because it carries out an appropriate sort of computation rather than because it supports a specific cognitive domain.
Current Opinion in Gastroenterology, 1999
Natural Language Semantics, 1993
Physics Letters B, 1981
ABSTRACT
Physics Letters B, 1980
Elastic and inelastic proton scattering from 191Ir, 193Ir and 194Pt have been studied at Ep = 50 ... more Elastic and inelastic proton scattering from 191Ir, 193Ir and 194Pt have been studied at Ep = 50 MeV. The E2 reduced transition rates obtained for the low-lying states in these nuclei agree qualitatively with the predictions of the supersymmetry scheme recently proposed for these nuclei.
Physical Review C, 1982
ABSTRACT
Lingua, 2005
Functional neuroimaging, within 10 years, has produced evidence which leads us to question a numb... more Functional neuroimaging, within 10 years, has produced evidence which leads us to question a number of the standard assumptions about the areas which are necessary and sufficient for language processing. Although neuroimaging evidence has corroborated much neuropsychological data, it forces a revision of a number of the standard interpretations of those data and some traditionally accepted notions must be totally discarded. We will provide an overview of some issues which have arisen in these years, giving examples from a number of laboratories and illustrating with experiments of our own. The circumstances under which the left posterior temporal lobe (Wernicke's area) and the left inferior frontal gyrus (Broca's area) are activated are reviewed, and several views of how they contribute to language processing are considered in the light of this evidence. Further evidence for the contribution of a number of other areas to language comprehension are reviewed, including the anterior temporal lobe, the cerebellum, the left superior median frontal lobe, the anterior insula and the left inferior temporal occipital junction. Further we discuss some of the conditions under which the right hemisphere contributes to language processing. We will conclude by discussing the implications of this research for the concept of modularity in the sense of Fodor [Modularity of Mind, MIT Press, Cambridge, 1983].
Brain Research, Mar 27, 2008
To determine the auditory event-related potential (AERP) correlates of phoneme perception in 17-m... more To determine the auditory event-related potential (AERP) correlates of phoneme perception in 17-month-old children at risk of dyslexia and controls, AERPs were elicited by standard (/bAk/) and deviant (/dAk/) word stimuli presented in an oddball paradigm. The at-risk children tended to show delayed P1 and P2 peaks for standard stimuli. Hemispheric group differences were observed for N2 amplitude and P1 latency, suggesting atypical processing of spoken words in at-risk children. Larger P2 and to a lesser extent P1 amplitudes following deviant words occurred in the control but not in the at-risk group, this may signal poorer phoneme discrimination in at-risk children. The present AERP results offer clues to where to look for a marker to identify children at high risk of reading and writing problems at an early age to facilitate early intervention.
Psychophysiology, 1999
Using positron emission tomography, visual presentation of sentences was shown to cause increased... more Using positron emission tomography, visual presentation of sentences was shown to cause increased regional cerebral blood flow relative to word lists in the left lateral anterior superior and middle temporal gyri, attributable to cognitive processes that occur during sentence comprehension in addition to those carried out during word comprehension. Additional comparisons showed that repeating words~in a different context, when subjects did not attempt to learn the initial lists! led to significant patterns of both increased blood flow~left putamen and right caudate! and decreased blood flow~left posterior temporal lobe!. Increases are argued to reflect retrieval of memory traces, whereas decreases reflect diminished necessity for processing of input. A decrease in the left inferior parietal lobe was attributable to other factors.
Brain and Language, 2004
In this paper we report the results of an experiment in which subjects read syntactically unambig... more In this paper we report the results of an experiment in which subjects read syntactically unambiguous and ambiguous sentences which were disambiguated after several words to the less likely possibility. Understanding such sentences involves building an initial structure, inhibiting the non-preferred structure, detecting that later input is incompatible with the initial structure, and reactivating the alternative structure. The ambiguous sentences activated four areas more than the unambiguous sentences. These areas are the left inferior frontal gyrus (IFG), the right basal ganglia (BG), the right posterior dorsal cerebellum (CB) and the left median superior frontal gyrus (SFG). The left IFG is normally activated when syntactic processing complexity is increased and probably supports that function in the current study as well. We discuss four hypotheses concerning how these areas may support comprehension of syntactically ambiguous sentences. (1) The left IFG, right CB and BG could support articulatory rehearsal used to support the processing of ambiguous sentences. This seems unlikely since the activation pattern associated with articulatory rehearsal in other studies is not similar to that seen here. (2) The CB acts as an error detector in motor processing. Error detection is important for recognizing that the wrong sentence structure has been chosen initially. (3) The BG acts to select and sequence movements in the motor domain and in cognitive domains may serve to inhibit competing and completed plans which is not unlike inhibiting the initially non-preferred structure or ''unchoosing'' the initial choice when incompatible syntactic input is received. (4) The left median SFG is relevant for the evaluation of plausibility. Evaluating the plausibility of the two possibilities provides an important basis for choosing between them. The notion of the use of domain general cognitive processes to support a linguistic process is in line with recent suggestions that the a given area may subserve a specific cognitive task because it carries out an appropriate sort of computation rather than because it supports a specific cognitive domain.
Current Opinion in Gastroenterology, 1999
Natural Language Semantics, 1993
Physics Letters B, 1981
ABSTRACT
Physics Letters B, 1980
Elastic and inelastic proton scattering from 191Ir, 193Ir and 194Pt have been studied at Ep = 50 ... more Elastic and inelastic proton scattering from 191Ir, 193Ir and 194Pt have been studied at Ep = 50 MeV. The E2 reduced transition rates obtained for the low-lying states in these nuclei agree qualitatively with the predictions of the supersymmetry scheme recently proposed for these nuclei.
Physical Review C, 1982
ABSTRACT
Lingua, 2005
Functional neuroimaging, within 10 years, has produced evidence which leads us to question a numb... more Functional neuroimaging, within 10 years, has produced evidence which leads us to question a number of the standard assumptions about the areas which are necessary and sufficient for language processing. Although neuroimaging evidence has corroborated much neuropsychological data, it forces a revision of a number of the standard interpretations of those data and some traditionally accepted notions must be totally discarded. We will provide an overview of some issues which have arisen in these years, giving examples from a number of laboratories and illustrating with experiments of our own. The circumstances under which the left posterior temporal lobe (Wernicke's area) and the left inferior frontal gyrus (Broca's area) are activated are reviewed, and several views of how they contribute to language processing are considered in the light of this evidence. Further evidence for the contribution of a number of other areas to language comprehension are reviewed, including the anterior temporal lobe, the cerebellum, the left superior median frontal lobe, the anterior insula and the left inferior temporal occipital junction. Further we discuss some of the conditions under which the right hemisphere contributes to language processing. We will conclude by discussing the implications of this research for the concept of modularity in the sense of Fodor [Modularity of Mind, MIT Press, Cambridge, 1983].
Brain Research, Mar 27, 2008
To determine the auditory event-related potential (AERP) correlates of phoneme perception in 17-m... more To determine the auditory event-related potential (AERP) correlates of phoneme perception in 17-month-old children at risk of dyslexia and controls, AERPs were elicited by standard (/bAk/) and deviant (/dAk/) word stimuli presented in an oddball paradigm. The at-risk children tended to show delayed P1 and P2 peaks for standard stimuli. Hemispheric group differences were observed for N2 amplitude and P1 latency, suggesting atypical processing of spoken words in at-risk children. Larger P2 and to a lesser extent P1 amplitudes following deviant words occurred in the control but not in the at-risk group, this may signal poorer phoneme discrimination in at-risk children. The present AERP results offer clues to where to look for a marker to identify children at high risk of reading and writing problems at an early age to facilitate early intervention.