1,721,003 research outputs found
(Ημι) αυθόρμητος λόγος σε ελληνόφωνα άτομα με μη ρέουσα αφασία: ανάλυση λαθών
No full textIntroduction: Aphasia is a speech and language disorder that often leaves other cognitive and mental functions intact. Patients with aphasia often have significant grammar problems. More specifically, Broca aphasia (non-fluent aphasia) is defined as a syndrome caused by a stroke in the left hemisphere and is characterized by various difficulties in speech and especially in literacy. However, as far as the literature is concerned, there are not enough empirical data to show the characteristics of this aphasia and in particular the analysis (semi) of spontaneous speech in Greek-speaking people with non-flowing aphasia. Purpose: the detection and analysis of errors in the production of (semi) spontaneous speech in Greek-speaking individuals with non-fluent aphasia and their comparison with healthy individuals. Methodology: The present dissertation is based on data from three individuals with non-fluent aphasia and three healthy individuals who formed the control group. All six participants were native speakers of Common Modern Greek. The group of people with non-fluent aphasia and the control group were of similar age and education. Three narrative speech extraction approaches were used to obtain the research data. Participants with aphasia, as well as healthy controls, were asked to describe a picture of the Cookie Thieft and then participants in both groups were interviewed and asked to answer some questions asked by the examiner. Results: The group of people with non-fluent aphasia had worse results than the control group. This was evident mainly from the difficulty in producing more complex grammatical sentences and more complex pronunciations. Conclusion: In the present study, as already expected, difficulties were identified in people with non-fluent aphasia, related to the production of syntactically complex and grammatically correct pronunciations. This group was compared with the control group and it was found that, indeed, the group of participants with non-fluent aphasia performed worse than the other team. However, there are few researches that have dealt with this issue, so it is necessary to have more.Εισαγωγή: Η αφασία είναι μια διαταραχή ομιλίας και γλώσσας που συχνά αφήνει ανέπαφες άλλες γνωστικές και νοητικές λειτουργίες. Οι ασθενείς με αφασία εμφανίζουν συχνά σημαντικά γραμματικά προβλήματα. Πιο συγκεκριμένα, η αφασία Broca (μη ρέουσα αφασία) ορίζεται ως ένα σύνδρομο που προκαλείται από εγκεφαλικό επεισόδιο στο αριστερό ημισφαίριο και χαρακτηρίζεται από διάφορες δυσκολίες στην ομιλία και κυρίως στον αγραμματισμό. Παρόλα αυτά, όσον αφορά την βιβλιογραφία δεν υπάρχουν επαρκείς εμπειρικά στοιχεία που να δείχνουν τα χαρακτηριστικά της αφασίας αυτής και ειδικότερα την ανάλυση (ημι)αυθόρμητου λόγου σε ελληνόφωνα άτομα με μη ρέουσα αφασία. Σκοπός: η ανίχνευση και η ανάλυση λαθών κατά την παραγωγή (ημι)αυθόρμητου λόγου σε ελληνόφωνα άτομα με μη ρέουσα αφασία και η σύγκριση τους με υγιή άτομα. Μεθοδολογία: Η παρούσα πτυχιακή εργασία βασίζεται σε δεδομένα τριών ατόμων με μη ρέουσα αφασία και τριών υγιών ατόμων που αποτελούσαν την ομάδα ελέγχου. Και οι έξι συμμετέχοντες ήταν φυσικοί ομιλητές της Κοινής Νέας Ελληνικής. Η ομάδα των ατόμων με μη ρέουσα αφασία και η ομάδα ελέγχου ήταν παρόμοιας ηλικίας και εκπαίδευσης. Για την απόκτηση των ερευνητικών δεδομένων χρησιμοποιήθηκαν τρεις προσεγγίσεις εξαγωγής αφηγηματικού λόγου. Οι συμμετέχοντες με αφασία, καθώς και οι υγιείς μάρτυρες, κλήθηκαν να περιγράψουν μια εικόνα το Cookie Thieft και στη συνέχεια, οι συμμετέχοντες και στις δύο ομάδες πήραν συνέντευξη και κλήθηκαν να απαντήσουν σε κάποιες ερωτήσεις που τους έθεσε ο εξεταστής. Aποτελέσματα: Η ομάδα ατόμων με μη ρέουσα αφασία παρουσίασε χειρότερα αποτελέσματα σε σχέση με την ομάδα ελέγχου. Αυτό φάνηκε κυρίως από την δυσκολία στην παραγωγή πιο σύνθετων προτάσεων γραμματικά και πιο πολύπλοκων εκφωνημάτων Οι συμμετέχοντες (μη ρέουσας αφασίας) παρήγαγαν πιο λίγες δομικά σύνθετες προτάσεις από ότι η αντίστοιχη ομάδα ελέγχου, στα περισσότερα δείγματα εκμαίευσης (ημι)αυθόρμητου λόγου. Συμπερασματικά: Στην παρούσα μελέτη, όπως ήταν ήδη αναμενόμενο, εντοπίστηκαν δυσκολίες σε άτομα με μη ρέουσα αφασία, που σχετίζονται με την παραγωγή συντακτικά πολύπλοκων και γραμματικά ορθών εκφωνήσεων. Συγκρίθηκε η ομάδα αυτή με την ομάδα ελέγχου και διαπιστώθηκε ότι, όντως, η ομάδα των συμμετεχόντων με μη ρέουσα αφασία είχε χειρότερη επίδοση, από ότι τα υγιή άτομα. Ωστόσο, υπάρχουν ελάχιστες έρευνες που ασχολήθηκαν με το συγκεκριμένο θέμα, επομένως είναι απαραίτητο να υπάρξουν περισσότερες.Complete
(Ημι) αυθόρμητος λόγος σε ελληνόφωνα άτομα με ρέουσα αφασία: ανάλυση λαθών
No full textIntroduction: Aphasia is the loss or weakening of the tongue caused by brain damage
(Berthier, 2005). Aphasia is a language disorder that can have a detrimental effect on the quality
of life. It is most often due to a stroke of the left hemisphere, but can also be caused by other
types of damage, such as trauma or neurodegenerative disease which they affect the lingual
network of the brain. (Fridriksson & Julius, 2021). Wernicke aphasia (WA) and Broca aphasia
(BA) have many challenges in performing language tasks. In each type of aphasia, the brain
and the function of the tongue are partially different (Azad, 2020). According to Azad (2020),
some critical speech deficits of patients with fluent aphasia (Wernicke type aphasia) are
reported, where their inability to recognize the referential meaning of words, more specifically
of abstract, strange, or more vocal words, is identified.
Purpose: The transcription and analysis connected speech of Greek-speaking people with
fluent aphasia, as well as healthy speakers of the Common Modern Greek Language.
Methodology: A sample of six participants was selected. More specifically, three participants
with flowing aphasia and three healthy ones were selected. All the people who took part in the
research were natural speakers of the Common Modern Greek Language. Healthy participants
were the control group, corresponding to the experimental group of participants with flowing
aphasia. Dr. Valantis Findanis and a speech therapist evaluated and diagnosed patients with
aphasia. Regarding the collection of data for conducting the research, three different ways of
sampling narrative speech were performed. Initially, all participants in the study (people with
aphasia and healthy people) were asked to describe the image of Cookie Theft, from the
weighted test of DEVA (Messini, Panagea, Kastellakis & Papathanassopoulos, 2013).
Participants were then asked to answer questions through an interview, where the questions
were specific and asked by the examiner. During the transcription of the speeches, they were
separated into grammatical and anti-grammatical sentences.
Results: Based on the results of the experimental group and the control group, there seemed to
be a significant difference between their total errors. Specifically, the experimental group
recorded a total of 207 errors, while the control group collected a total of 94 errors. Most errors
in all participants of both groups were dictionary errors. However, there was a big difference
in the number of errors between the two groups. Conclusions: People with fluent aphasia and healthy people, according to their narrative
speech, show mainly phonological and semantic paraphrase features. Also, phonological errors
can not occur in the speech of people with fluent aphasia. Patients with flowing aphasia often
experience especially omissions of phonemes and syllables, followed by a variety of phoneme
replacements.Εισαγωγή: Η αφασία αποτελεί την απώλεια ή την εξασθένηση της γλώσσας που προκαλείται
από εγκεφαλική βλάβη (Berthier, 2005). Η αφασία είναι μια γλωσσική διαταραχή που μπορεί
να έχει βαθιές αρνητικές επιπτώσεις στην ποιότητα ζωής. Τις περισσότερες φορές οφείλεται
σε εγκεφαλικό επεισόδιο του αριστερού ημισφαιρίου, αλλά μπορεί επίσης να προκληθεί από
άλλους τύπους βλάβης, όπως τραύμα ή νευροεκφυλιστική νόσο όπου επηρεάζουν το
γλωσσικό δίκτυο του εγκεφάλου. (Fridriksson & Julius, 2021). Η αφασία Wernicke (WA) και
η αφασία Broca (BA) έχουν πολλές προκλήσεις στην εκτέλεση γλωσσικών εργασιών. Σε κάθε
τύπο αφασίας, ο εγκέφαλος και η λειτουργία της γλώσσας είναι μερικώς διαφορετικοί (Azad,
2020). Σύμφωνα με τον Azad (2020), αναφέρονται μερικά κρίσιμα ελλείματα ομιλίας των
ασθενών με ρέουσα αφασία (αφασία τύπου Wernicke), όπου εντοπίζεται η αδυναμία τους να
αναγνωρίσουν την αναφορική σημασία των λέξεων, πιο συγκεκριμένα των αφηρημένων,
παράξενων ή φωνηματικά περίεργων λέξεων.
Σκοπός: Η μεταγραφή και η ανάλυση (ημι)αυθόρμητου λόγου ελληνόφωνων ατόμων με
ρέουσα, καθώς και υγιών ομιλητών της Κοινής Νεοελληνικής Γλώσσας.
Μεθοδολογία: Επιλέχθηκε δείγμα από έξι συμμετέχοντες. Αναλυτικότερα, επιλέχθηκαν τρεις
συμμετέχοντες με ρέουσα αφασία και τρείς υγιείς. Όλα τα άτομα που έλαβαν μέρος στην
έρευνα ήταν φυσική ομιλητές της Κοινής Νεοελληνικής Γλώσσας. Οι υγιείς συμμετέχοντες
αποτελούσαν την ομάδα ελέγχου, που αντιστοιχεί στην πειραματική ομάδα των
συμμετεχόντων με ρέουσα αφασία. Ο Δρ. Βαλάντης Φυνδάνης και μία λογοθεραπεύτρια
αξιολόγησαν και διάγνωσαν τους ασθενείς με αφασία. Όσον αφορά την συλλογή των
δεδομένων για την διεξαγωγή της έρευνας, πραγματοποιήθηκαν τρεις διαφορετικοί μέθοδοι
λήψης δείγματος αφηγηματικού λόγου. Αρχικά, όλοι οι συμμετέχοντες της έρευνας (άτομα με
αφασία και υγιή άτομα) καλέστηκαν να περιγράψουν την εικόνα Κλοπής Μπισκότου (Cookie
Theft), από την σταθμισμένη δοκιμασία της ΔΕΒΑ (Μεσσήνης, Παναγέα, Καστελλάκης &
Παπαθανασόπουλος, 2013). Στη συνέχεια, οι συμμετέχοντες κλήθηκαν να απαντήσουν σε
ερωτήσεις μέσω συνέντευξης, όπου οι ερωτήσεις ήταν συγκεκριμένες και γίνονταν από ον
εξεταστή. Κατά την μεταγραφή των εκφωνημάτων έγινε ο διαχωρισμός τους σε γραμματικές
και αντιγραμματικές προτάσεις. Aποτελέσματα: Με βάση τα αποτελέσματα της πειραματικής ομάδας και της ομάδας ελέγχου
φάνηκε να υπάρχει μία μεγάλη διαφορά ανάμεσα στο σύνολο των λαθών τους. Συγκεκριμένα,
η πειραματική ομάδα σημείωσε συνολικά 207 λάθη, ενώ η ομάδα ελέγχου συγκέντρωσε
συνολικά 94 λάθη. Τα περισσότερα λάθη σε όλους τους συμμετέχοντες και των δύο ομάδων
αποτέλεσαν τα λεξικά λάθη. Όμως, υπήρξε μεγάλη διαφορά όσον αφορά των αριθμών των
λαθών ανάμεσα στις δύο ομάδες.
Συμπεράσματα: Τα άτομα με ρέουσα αφασία και τα υγιή άτομα, κατά τον αφηγηματικό τους
λόγο, παρουσιάζουν κυρίως χαρακτηριστικά φωνολογικής και σημασιολογικής παραφασίας.
Επίσης τα φωνολογικά λάθη δεν μπορούν να παραληφθούν από τον λόγο των ατόμων με
ρέουσα αφασία. Οι ασθενείς με ρέουσα αφασία συχνά παρουσιάζουν κυρίως παραλείψεις
φωνημάτων και συλλαβών και ακολούθως ποικίλες αντικαταστάσεις φωνημάτων.Complete
Short-term Memory and Language Processing: Extending an Interactive Model to Capture Sentence-Level Data
No full textLinguistic theory and aphasia:an overview
No full textBackground: Aphasia research has been informed by linguistic theory to a great extent. Conversely, linguistic theory has also been informed by data from people with aphasia, albeit to a lesser extent.Aims: This overview to the Special Issue of Aphasiology entitled “Aphasia and linguistic theory: What we have captured so far” presents a narrative review that aims to illustrate the contribution of linguistic theory to aphasia research, and also includes a section that presents the articles making up the special issue. The narrative review, which is not exhaustive, highlights influential theoretical frameworks and linguistic constructs that have been central to accounts of language impairment in aphasia.Main Contribution: The overview illustrates the contribution of linguistic theory to aphasiology and paves the way for the development of a unified approach to aphasia, which will incorporate insights not only from theoretical linguistics, but also from other complementary fields, such as psycholinguistics, cognitive (neuro)psychology, and neuroscience of language.</p
Morphosyntactic production in agrammatic aphasia: A cross-linguistic machine learning approach
No full textIntroduction Recent studies on agrammatic aphasia by Fyndanis et al. (2012, 2017) reported evidence against the cross-linguistic validity of unitary accounts of agrammatic morphosyntactic impairment, such as the Distributed Morphology Hypothesis (DMH) (Wang et al., 2014), the two versions of the Interpretable Features’ Impairment Hypothesis (IFIH-1: Fyndanis et al., 2012; IFIH-2: Fyndanis et al., 2018b), and the Tree Pruning Hypothesis (TPH) (Friedmann & Grodzinsky, 1997). However, some of the features/factors emphasized by the accounts above (i.e. involvement of inflectional alternations (DMH), involvement of integration processes (IFIH-1), involvement of both integration processes and inflectional alternations (IFIH-2), position of a morphosyntactic feature/category in the syntactic hierarchy (TPH)) may still play a role in agrammatic morphosyntactic production. These features may act in synergy with other factors in determining the way in which morphosyntactic production is impaired across persons with agrammatic aphasia (PWA) and across languages. Relevant factors may include language-independent and language-specific properties of morphosyntactic categories, as well as subject-specific and task/material-specific variables. The present study addresses which factors determine verb-related morphosyntactic production in PWA and what is their relative importance. Methods We collapsed the datasets of the 24 Greek-, German-, and Italian-speaking PWA underlying Fyndanis et al.’s (2017) study, added the data of two more Greek-speaking PWA, and employed machine learning algorithms to analyze the data. The unified dataset consisted of data on subject-verb agreement, time reference (past reference, future reference), grammatical mood (indicative, subjunctive), and polarity (affirmatives, negatives). All items/conditions were represented as clusters of theoretically motivated features: ±involvement of integration processes, ±involvement of inflectional alternations, ±involvement of both integration processes and inflectional alternations, and low/middle/high position in the syntactic hierarchy. We included 14 subject-specific, category-specific and task/material-specific predictors: Verbal Working Memory (WM), (years of formal) Education, Age, Gender, Mean Length of Utterance in (semi)spontaneous speech (Index 1 of severity of agrammatism), Proportion of Grammatical Sentences in (semi)spontaneous speech (Index 2 of severity of agrammatism), Words per Minute in (semi)spontaneous speech (Index of fluency), Involvement of inflectional alternations, Involvement of integration processes, Involvement of both integration processes and inflectional alternations, Position of a given morphosyntactic category in the syntactic hierarchy (high, middle, low), Item Presentation mode (cross-modal, auditory), Response mode (oral, written), and Language (Greek, German, Italian). Different machine learning models were employed: Random Forest, C5.0 decision tree, RPart, and Support Vector Machine. Results & Discussion Random Forest model outperformed all the other models achieving the highest accuracy (0.786). As shown in Figure 1, the best predictors of accuracy on tasks tapping morphosyntactic production were the involvement of both integration processes and inflectional alternations (categories involving both integration processes and inflectional alternations were more impaired than categories involving one or neither of them), verbal WM capacity (the greater the WM capacity, the better the morphosyntactic production), and severity of agrammatism (the more severe the agrammatism, the worse the morphosyntactic production). Results are consistent with IFIH-2 (Fyndanis et al., 2018b) and studies highlighting the role of verbal WM in morphosyntactic production (e.g., Fyndanis et al., 2018a; Kok et al., 2007)
Pathological language-switching/mixing and its relationship to domain-general cognitive control
No full textThis chapter constitutes a narrative review on the so-called pathological language mixing and switching, with primary focus on multilingual persons with aphasia. Domain-general cognitive control is assumed to be a central aspect of bilingual language use and is strongly involved in switching between languages. However, this assumed relationship has not received the empirical scrutiny it deserves. In this review, we ask whether and when language switching/mixing in brain-damaged participants should be considered a control deficit and when it can be better characterized as a communicative strategy of the participants. We present opposing views on the legitimacy of using the term pathological switching/mixing and propose a way of reconciling these views. We also ask to what extent possible language control deficits underlying so-called pathological switching/mixing overlap with domain-general cognitive control functions, as measured by tasks of executive functions, and look into the neural correlates of these functions. This question addresses the relationship between language control and domain-general cognitive control. It therefore also touches upon the underlying assumptions behind the idea that frequent language switching/mixing could train cognitive control functions, possibly leading to a bilingual advantage in cognitive abilities, a hotly debated topic
Functional categories in greek agrammatism
No full textThe present study, which is conducted within the general framework of Generative Grammar (Chomsky, 1981; 1995 and thereafter), investigates the ability of three Greek-speaking agrammatic aphasics to handle (in both production and comprehension) a number of functional categories: Complementizer (C), Negation (Neg), Agreement (Agr), Tense (T), and Aspect (Asp). To test these categories, a series of structured tasks were administered (e.g. question elicitation task, constituent ordering task, truth-value judgement task, sentence completion task, sentence grammaticality judgement task, sentence completion task, sentence grammatically judgement task, sentence repetition task, etc). Apart from the afore-mentioned categories, the effect of some other variables on the agrammatic performance was also explored, such as the frequency of occurrence and the morphological regularity of the verb, as well as the structural complexity of the sentence. One of the principle goals of this study is to test some accounts of agrammatism proposed so far, such as the Tree Pruning Hypothesis (TPH) (Friedmann & Grodzinsky, 1997) and the Interpretable Features’ Impairment Hypothesis (IFIH) (Nanousi, Masterson, Druks, & Atkinson, 2006; Varlokosta, Valeonti, Kakavoulia, Lazaridou, Economou, & Protopapas, 2006). According to TPH, agrammatism arises from deletion or ‘pruning’ of the syntactic tree at the T node. TPH predicts that everything above T is lost while material below is preserved. On the other hand, IFIH is not structural/hierarchical in nature, as it predicts that in agrammatism the most severe impairment will involve the functional categories with interpretable features (such as T and Asp) rather than the ones with uninterpretable features (such as Agr). The results of the present study are in line with IFIH, since T, Asp, Neg and C –which all bear interpretable features– were found to be severely impaired, while Agr was found relatively spared. In contrast, given that Asp is lower that T and Agr in the Greek syntactic hierarchy (Philippaki-Warburton, 1998), these results cannot be accountted for by TPH. Apart from reinforcing the descriptive adequacy of IFIH, this study aimed at developing its interpretative enrichment as well. More specifically, on the basis of the quantitative and qualitative aspects of the agrammatic patterns of our participants, it is argued that they have two deficits: a linguistic one, which is mainly syntactic in nature affecting functional categories across the board, and a “psychological/cognitive” one, namely a limitation of processing resources. Therefore, it is suggested that what renders the categories with interpretable features more vulnerable than those with uninterpretable features is the synergistic effect of three facts: i) agrammatic speakers (at least the ones participated in the present study) suffer from a reduction of processing resources, ii) they have a syntactic deficit affecting functional categories, and iii) the categories with interpretable features are more demanding in terms of processing resources, as they require integration of grammatical and conceptual knowledge. In contrast, implementation of only grammatical knowledge is sufficient for “uninterpretable” categories like Agr. Finally, similar but not identical patterns of performance were observed across different modalities (comprehension and production), reinforcing the weak (and not the strong) parallelism between them and, thus, providing empirical support to Grodzinsky’s claim (2000: 18) that there is anatomical proximity, but functional separation between production and comprehension mechanisms.Αντικείµενο της παρούσας µελέτης είναι η διερεύνηση της υπόστασης των λειτουργικών κατηγοριών στα ελληνόφωνα άτοµα µε αγραµµατισµό. Ειδικότερα, οι προς διερεύνηση λειτουργικές κατηγορίες είναι o συµπληρωµατικός δείκτης (Σ∆), η άρνηση, η συµφωνία, ο χρόνος και η όψη. Ο έλεγχος αυτών των κατηγοριών, που αφορά τόσο την παραγωγή όσο και την κατανόηση, πραγµατοποιείται µέσω της διενέργειας µιας σειράς από δοµηµένες δοκιµασίες, όπως είναι η δοκιµασία εκµαίευσης ερωτήσεων, η δοκιµασία διάταξης συστατικών, η δοκιµασία κρίσης αληθειακής τιµής, η δοκιµασία συµπλήρωσης πρότασης, η δοκιµασία κρίσης γραµµατικότητας πρότασης κ.ά. Επίσης, πέρα από τις παραπάνω λειτουργικές κατηγορίες, εξετάζεται και η επίδραση άλλων παραµέτρων στην αγραµµατική επίδοση, όπως είναι η συχνότητα και η (µορφολογική) οµαλότητα του ρήµατος, καθώς και η δοµική πολυπλοκότητα της πρότασης. Το θεωρητικό πλαίσιο αυτής της µελέτης, πέρα από τις έννοιες που συνδέονται µε την αφασία και τον αγραµµατισµό και πέρα από τα ευρήµατα και πορίσµατα των σχετικών νευρογλωσσολογικών ερευνών που έχουν πραγµατοποιηθεί, έχει διττή ταυτότητα: τη γλωσσολογική και την ψυχολογική. Γλωσσολογικό υπόβαθρο αποτελεί το ευρύτερο πλαίσιο της γενετικής γραµµατικής, όπως αυτό ορίζεται βάσει των πιο πρόσφατων εκδοχών της: του προτύπου κυβέρνησης και αναφορικής δέσµευσης (Chomsky, 1981, 1986α,β) και του µινιµαλιστικού προγράµµατος (Chomsky, 1993, 1994, 1995α,β, 2000, 2001). Το ψυχολογικό υπόβαθρο συγκροτείται από τις σχετικές έννοιες που απαντούν στη βιβλιογραφία (π.χ. ενεργοποίηση αναπαραστάσεων, πόροι επεξεργασίας, βραχυπρόθεσµη µνήµη ή µνήµη εργασίας κ.λπ.), καθώς και από κάποια µοντέλα της βραχυπρόθεσµης µνήµης που είτε άσκησαν µεγάλη επίδραση στο πεδίο της νευροψυχολογίας (π.χ. Baddeley & Hitch, 1974) είτε εστιάζουν ειδικότερα στη γλώσσα, αποτελώντας έτσι χρήσιµα εργαλεία ανάλυσης των αγραµµατικών δεδοµένων (π.χ. Ν. Martin & Saffran, 1992, 1997• R. Martin, Lesch & Bartha, 1999). Αυτή η εργασία, µε την εξέταση των λειτουργικών κατηγοριών στον ελληνικό αγραµµατισµό, φιλοδοξεί –µεταξύ άλλων– να εµπλουτίσει τη βάση των σχετικών δεδοµένων που αφορούν ειδικότερα την Ελληνική, καθώς και να ενισχύσει το διαγλωσσικό έλεγχο της εγκυρότητας διάφορων ερµηνειών του αγραµµατισµού που έχουν προταθεί µέχρι σήµερα (όπως είναι, µεταξύ άλλων, η υπόθεση της αποκοπής του (συντακτικού) δέντρου (Friedmann & Grodzinsky, 1997) και η υπόθεση της διαταραχής των ερµηνεύσιµων χαρακτηριστικών (Nanousi, Masterson, Druks & Atkinson, 2006• Varlokosta, Valeonti, Kakavoulia, Lazaridou, Economou & Protopapas, 2006). [...
(Morpho)syntactic comprehension in agrammatic aphasia : Evidence from Greek
No full textBackground: A number of hypotheses have been formulated to account for comprehension data in agrammatic aphasia. They explain deficits in comprehending specific structures, such as semantically reversible non-canonical sentences, for example, Trace Deletion Hypothesis (TDH, Grodzinsky, 1986, 1990, 1995), or functional categories, for example, Tree Pruning Hypothesis (TPH, e.g., Friedmann, 2006); Tense Underspecification Hypothesis (TUH, Wenzlaff & Clahsen, 2004, 2005); Interpretable Features' Impairment Hypothesis (IFIH; e.g., Varlokosta et al., 2006). Several studies, however, report evidence contradicting these theories (e.g., Caramazza, Capasso, Capitani, & Miceli, 2005; Dickey, Milman, & Thompson, 2008) and propose new accounts to explain the comprehension deficits in agrammatic aphasia, for example, Distributed Morphology Account (DMA, Dickey et al., 2008). Aims: Against the background above, this study investigates the ability of three Greek-speaking agrammatic individuals to comprehend a wide range of structures and functional categories: semantically reversible (canonical) active and (non-canonical) passive sentences, Complementizer Phrase, subject-verb Agreement, Tense, and Aspect. Methods & Procedures: We administered: (a) two sentence-picture matching tasks to test comprehension of reversible active and passive sentences, and Tense; (b) a sentence grammaticality judgement task to test judgement of Tense, Aspect, and subject-verb Agreement; and (c) a picture-pointing task to test comprehension of Complementizer Phrase. Outcomes & Results: (a) Two of the three agrammatic participants performed at chance on reversible passive sentences and above chance on active sentences. The third participant performed equally high on the two sentence types. Two participants performed at chance on Tense comprehension and one above chance. (b) The three participants were selectively or across-the-board impaired in judgement of Agreement, Tense, and Aspect. One of the two selectively affected participants had chance performance on Aspect and above chance performance on Agreement and Tense. The other one performed at chance on Aspect and Tense, and above chance on Agreement. The third participant's performance was equally poor on all three categories. (c) All three agrammatic participants performed above chance on the comprehension of Complementizer Phrase. Conclusions: In comprehension/judgement, canonical and non-canonical sentences do not dissociate in all agrammatic speakers, while functional categories associated with the verb morphology may be compromised in the face of relatively well-preserved categories that are located higher in the syntactic hierarchy. All three agrammatic participants support the DMA, and two of them support the TDH. Instead, none of them provided support to the TPH, TUH, and IFIH. © 2013 Copyright Taylor and Francis Group, LLC
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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