Clinical and structural disconnectome evaluation in a case of optic aphasia.

Optic Aphasia (OA) and Associative Visual Agnosia (AVA) are neuropsychological disorders characterized by impaired naming on visual presentation. From a cognitive point of view, while stimulus identification is largely unimpaired in OA (where access to semantic knowledge is still possible), in AVA it is not. OA has been linked with right hemianopia and disconnection of the occipital right-hemisphere (RH) visual processing from the left hemisphere (LH) language areas.In this paper, we describe the case of AA, an 81-year-old housewife suffering from a deficit in naming visually presented stimuli after left occipital lesion and damage to the interhemispheric splenial pathway. AA has been tested through a set of tasks assessing different levels of visual object processing. We discuss behavioral performance as well as the pattern of lesion and disconnection in relation to a neurocognitive model adapted from Luzzatti and colleagues (1998). Despite the complexity of the neuropsychological picture, behavioral data suggest that semantic access from visual input is possible, while a lesion-based structural disconnectome investigation demonstrated the splenial involvement.Altogether, neuropsychological and neuroanatomical findings support the assumption of visuo-verbal callosal disconnection compatible with a diagnosis of OA.

Assessment of verb and sentence processing deficits in stroke-induced aphasia: the Italian version of the Northwestern Assessment of Verbs and Sentences (NAVS-I).

Background: The Northwestern Assessment of Verbs and Sentences (NAVS) assesses verb and sentence production and comprehension in aphasia. Results from the original English version and from its adaptation to German have shown that the NAVS is able to capture effects of verb-argument structure (VAS) complexity (i.e., lower accuracy for two- and three-argument vs. one-argument verbs) and syntactic complexity (i.e., lower accuracy for non-canonical vs. canonical sentences) in both agrammatic participants and individuals with mild (residual) forms of aphasia. The NAVS has been recently adapted to Italian (NAVS-I) and tested on a group of healthy participants, with results showing longer reaction times to complex vs. simple verbs and sentences. Aims: The present study aimed to test the ability of NAVS-I to i) capture verb/sentence production and comprehension deficits in Italian-speaking individuals with agrammatism or with fluent aphasia, and ii) differentiate individuals with aphasia from healthy age-matched participants, with the overall goal to validate its use in clinical practice. Methods & Procedures: Forty-four healthy participants and 28 individuals with aphasia (10 with agrammatic speech production) were administered the NAVS-I, which includes tasks assessing production and comprehension of verbs requiring one, two or three arguments, as well as production and comprehension of canonical and non-canonical sentences. Outcomes & Results: On the Verb Naming Task (VNT), better production of one- (vs. two- and three-) argument verbs was found in the agrammatic group, whereas, verb production in the fluent group was solely predicted by word length and imageability. No effects of argument optionality (i.e., greater difficulty for optionally transitive verbs than for 1-argument verbs) were found. Sentence-level tasks found no differences between the agrammatic and the fluent group in production or comprehension of both canonical and non-canonical sentences; rather, sentence comprehension accuracy was predicted by demographic variables and by aphasia severity. At the individual level, performance on the NAVS-I was significantly different from that of healthy speakers in 26/28 patients. Conclusions: Data show that the NAVS-I is able to capture effects of argument structure complexity in verb production, and effects of syntactic complexity in sentence production and comprehension. In addition, our results point to verb production as the task with greater capability to differentiate agrammatism from other (fluent) forms of aphasia. The study provides support for the use of the NAVS-I in the diagnosis of aphasia, as it is able to detect language deficits at the individual level, even in participants with mild (residual) forms of aphasia.

Lateralized reading in the healthy brain: A behavioral and computational study on the nature of the visual field effect.

Despite its widespread use to measure functional lateralization of language in healthy subjects, the neurocognitive bases of the visual field effect in lateralized reading are still debated. Crucially, the lack of knowledge on the nature of the visual field effect is accompanied by a lack of knowledge on the relative impact of psycholinguistic factors on its measurement, thus potentially casting doubts on its validity as a functional laterality measure. In this study, an eye-tracking-controlled tachistoscopic lateralized lexical decision task (Experiment 1) was administered to 60 right-handed and 60 left-handed volunteers and word length, orthographic neighborhood, word frequency, and imageability were manipulated. The magnitude of visual field effect was bigger in right-handed than in left-handed participants. Across the whole sample, a visual field-by-frequency interaction was observed, whereby a comparatively smaller effect of word frequency was detected in the left visual field/right hemisphere (LVF/RH) than in the right visual field/left hemisphere (RVF/LH). In a subsequent computational study (Experiment 2), efficient (LH) and inefficient (RH) activation of lexical orthographic nodes was modelled by means of the Naïve Discriminative Learning approach. Computational data simulated the effect of visual field and its interaction with frequency observed in the Experiment 1. Data suggest that the visual field effect can be biased by word frequency. Less distinctive connections between orthographic cues and lexical/semantic output units in the RH than in the LH can account for the emergence of the visual field effect and its interaction with word frequency.

The Semantic Association Test (SAT): normative data from healthy Italian participants and a validation study in aphasic patients.

The Semantic Association Test assesses several aspects of Semantic Memory (Categorical, Encyclopedic, Functional, and Visual Encyclopedic associations: CAs, EAs, FAs and VEAs), using a picture-to-picture matching paradigm. Normative data were collected from a group of 329 healthy participants (178 females) with mean 51.1 (range 20-90) years of age and mean 11.89 (range 5-19) years of education. Raw scores of healthy participants, pre-calculated correction factors for age and educational level, and Equivalent Scores are provided. The SAT was validated in a sample of 139 left brain-damaged persons with aphasia (PWA). Both groups (healthy participants and PWA) scored worse in the CA and EA conditions. The performance of the PWA group was overall defective, and global aphasics scored worse than persons with other types of aphasia. However, several PWA did not show impairments in the SAT. Dissociations were also found, with individual PWA showing defective performance confined to a single category. These results present the SAT as a tool that is useful to detect impairments of visual Semantic Memory, providing normative data from healthy participants and a validation study in PWA.

Agency of Subjects and Eye Movements in Schizophrenia Spectrum Disorders.

People with schizophrenia spectrum disorders (SSD) show anomalies in language processing with respect to "who is doing what" in an action. This linguistic behavior is suggestive of an atypical representation of the formal concepts of "Agent" in the lexical representation of a verb, i.e., its thematic grid. To test this hypothesis, we administered a silent-reading task with sentences including a semantic violation of the animacy trait of the grammatical subject to 30 people with SSD and 30 healthy control participants (HCs). When the anomalous grammatical subject was the Agent of the event, a significant increase of Gaze Duration was observed in HCs, but not in SSDs. Conversely, when the anomalous subject was a Theme, SSDs displayed an increased probability of go-back movements, unlike HCs. These results are suggestive of a higher tolerability for anomalous Agents in SSD compared to the normal population. The fact that SSD participants did not show a similar tolerability for anomalous Themes rules out the issue of an attention deficit. We suggest that general communication abilities in SSD might benefit from explicit training on deep linguistic structures.

A verb-naming test accurately detects cognitive changes in ALS.

Verb-naming tests were proposed for detecting cognitive impairment in ALS, although statistical evidence on their clinical usefulness is still lacking. A total of 29 ALS patients and 29 demographic-matched healthy controls (HCs) were administered the Action-Verb-Naming Test (AVNT), a standardized picture-naming task of actions. Patients were also administered the Edinburgh Cognitive and Behavioral ALS Screen (ECAS), and classified according to Strong et al. (Amyotrophic lateral sclerosis-frontotemporal spectrum disorder (ALS-FTSD): revised diagnostic criteria. Amyotroph Lateral Scler Frontotemporal Degener. 2017;18:153-4) criteria. The AVNT discriminated ALS patients from HCs (p = 0.026) and yielded high accuracy in detecting cognitive impairments among ALS patients (88% of accuracy; sensitivity = 1; specificity = 0.84; PPV = 0.5; NPV = 1; LR+ = 3.83; LR- = 0), as well as a below-cutoff performance on the ECAS (AUC = 0.74). The AVNT was unrelated to other clinical variables, despite being strongly associated with ECAS total, ALS-specific, Language and Executive scores (rs = 0.65-0.75). These findings show that verb naming is an accurate test to detect domain-specific cognitive changes in ALS patients, regardless of their disease phenotype.

Processing Argument Structure and Syntactic Complexity in People with Schizophrenia Spectrum Disorders.

INTRODUCTION: Deficits in language comprehension and production have been repeatedly observed in Schizophrenia Spectrum Disorders (SSD). However, the characterization of the language profile of this population is far from complete, and the relationship between language deficits, impaired thinking and cognitive functions is widely debated. OBJECTIVE: The aims of the present study were to assess production and comprehension of verbs with different argument structures, as well as production and comprehension of sentences with canonical and non-canonical word order in people with SSD. In addition, the study investigated the relationship between language deficits and cognitive functions. METHODS: Thirty-four participants with a diagnosis of SSD and a group of healthy control participants (HC) were recruited and evaluated using the Italian version of the Northwestern Assessment of Verbs and Sentences (NAVS, Cho-Reyes & Thompson, 2012; Barbieri et al., 2019). RESULTS: Results showed that participants with SSD were impaired - compared to HC - on both verb and sentence production, as well as on comprehension of syntactically complex (but not simple) sentences. While verb production was equally affected by verb-argument structure complexity in both SSD and HC, sentence comprehension was disproportionately more affected by syntactic complexity in SSD than in HC. In addition, in the SSD group, verb production deficits were predicted by performance on a measure of visual attention, while sentence production and comprehension deficits were explained by performance on measures of executive functions and working memory, respectively. DISCUSSION: Our findings support the hypothesis that language deficits in SSD may be one aspect of a more generalized, multi-domain, cognitive impairment, and are consistent with previous findings pointing to reduced inter- and intra-hemispheric connectivity as a possible substrate for such deficits. The study provides a systematic characterization of lexical and syntactic deficits in SSD and demonstrates that psycholinguistically-based assessment tools may be able to capture language deficits in this population.

The autocracy of meaning: Intact visuo-imitative processes may not compensate for meaningful gestures.

The dual-route models of action distinguish between a semantic and a non-semantic visuo-motor route to execute different types of gestures. Despite the large amount of evidence in support to the model, some aspects are debated. One issue concerns the recruitment of the visuo-motor route to correctly execute meaningful gestures when the semantic route is damaged. Debated predictions of the dual-route model were investigated in a sample of 32 patients with left hemisphere stroke lesions compared to 27 healthy controls. Group analysis showed that patients were equally impaired on meaningful and meaningless gestures. Single-case analysis demonstrated that most cases were more impaired on meaningful than on meaningless gestures both when they are given in separate lists and when they are intermingled. Impaired performance on the imitation of meaningful gestures in both the separate and mixed list but spared performance on meaningless gestures in the separate list is against the hypothesis that the intact visuo-motor route compensates for damage to the semantic route. These results suggest that the damaged semantic route interferes with the visuo-motor route and prevents the processing of meaningful gestures along the visuo-motor route. Furthermore, an explorative analysis was conducted to investigate the relationship between gestures imitation and pantomime of object use on verbal command and between gestures imitation and performance on linguistic tasks. Although no significant correlation emerged, patients with moderate/severe impairment on the AAT performed significantly worse on meaningful, but not on meaningless gestures than patients with mild/minimal language impairment, suggesting that praxis and language systems are independent but dynamically interact.

Some evidence on Gerstmann's syndrome: A case study on a variant of the clinical disorder.

We describe the case of a bilingual patient with persistent symptoms largely, although not fully, consistent with those that are usually reported in Gerstmann's syndrome. Twenty months after a spontaneous primary intracranial hemorrhage, the patient was evaluated with a series of neuropsychological tasks and underwent an MRI investigation based on Diffusion Tensor Imaging probabilistic tractography. The patient suffered from dysgraphia (difficulty in the access to the graphemic representation of letter forms), autotopoagnosia (difficulties in locating body parts on verbal command), right-left confusion (difficulties in localizing right and left side of symmetrical body parts), and number processing/calculation impairments (predominant difficulties on transcoding tasks). Probabilistic tractography revealed a relatively spared superior longitudinal fasciculus and severe damage to the subcortical white matter connecting the angular gyrus with other parietal regions, such as the intraparietal sulcus and the supramarginal gyrus. Within the framework of the contemporary cognitive accounts of Gerstmann's syndrome, the case supports the assumption of an anatomical intraparietal disconnection more than a functional Grundstörung (core impairment).

Diagnostic Accuracy of Noun- and Verb-Naming Tasks in Detecting Cognitive Impairment in Parkinson's Disease.

BACKGROUND: In Parkinson's disease (PD), verb-naming tasks (VNTs) have been proposed as superior to noun-naming ones in detecting language deficits, although such a hypothesis is not supported at a statistical level. OBJECTIVES: The main aim of this study was to provide diagnostic accuracy evidence for a VNT and noun-naming task (NNT) in detecting cognitive impairment (CI) in PD patients. METHOD: Thirty-three consecutive PD patients were subdivided into participants with (PD-CI; N = 12) or without CI (cognitively unimpaired, PD-CU; N = 21), based on a raw score ≤25 or >25 on the Mini-Mental State Examination, respectively. The NNT and VNT by Neuropsychologia [2006 Jan;44(1):73-89] were administered. Diagnostic accuracy of the NNT and VNT was assessed through receiver-operating characteristics analyses by comparing PD-CU to PD-CI patients. At the optimal cut-off, sensitivity, specificity, positive and negative predictive values (PPV, NPV), and likelihood ratios (LR+, LR-) were separately tested for the NNT and VNT against PD-CU versus PD-CI classification. RESULTS: Diagnostic accuracy was higher for the NNT (AUC = 0.85; p = 0.001) versus the VNT (AUC = 0.68; p = 0.092). Consistently, the NNT yielded higher sensitivity, specificity, and post-test features than the VNT (NNT: sensitivity = 0.75, specificity = 0.81, PPV = 0.69, NPV = 0.85, LR+ = 3.94, LR- = 0.31; VNT: sensitivity = 0.67, specificity = 0.67, PPV = 0.53, NPV = 0.78, LR+ = 2, LR- = 0.5). CONCLUSIONS: In accordance with the Movement Disorders Society guidelines, NNTs are diagnostically sound psychometric instruments to discriminate PD patients with versus without CI. However, these findings need replication by (1) employing a gold standard different from the Mini-Mental State Examination, which does not capture the full range of CI in this population and (2) subdividing PD patients into those with mild CI and dementia.

Johann Jakob Wepfer (1620-1695): A review of his contributions to neuropsychology on the quadricentennial of his birth.

The effects of brain damage on behavior have been reported by authors from the Greek, Roman, Medieval, Renaissance, and seventeenth-century medical traditions. However, few of the reported cases discussed mind-brain relationships, even fewer reported data that offered a description of cognitive functions, and none described a clear association of a functional mechanism of cognitive impairment with identifiable focal brain damage. An exception is found in the case studies by Johann Jakob Wepfer (1620-1695). After reviewing the pre-seventeenth-century background and Wepfer's milieu, we analyze his texts on neuroanatomy, apoplexy, and brain vascularization (Observationes anatomicae ex cadaveribus eorum, quos sustulit apoplexia cum exercitatione de ejus loco affecto) and his remarkable collection of 222 neurological cases (Observationes medico-practicae de affectibus capitis internis & externis), posthumously published in 1727. We focus on his reports concerning on the presence of aphasia, memory disorders, and unilateral neglect, correlated with focal brain damage, with particular emphasis on his examination of language impairments.

Open-source open-access reaction time test (OORTT): an easy tool to assess reaction times.

The speed of information processing is one of the most reliable indices of cognitive efficiency. The most common way to evaluate this ability is to assess reaction times (RTs). The technical limitations of previous tasks, aimed at measuring RT, have motivated us to develop a new battery for their evaluation. The aim of this study is to build an open-source, open-access reaction time test (OORTT), which has the following characteristics: rapid and easy administration, robust Italian normative data based on a wide age range, a simple scoring system, compatibility with all operating systems, no license or activation costs, and based on an open-source software platform. The battery is composed of three tasks: simple reaction times (SRT), Go/No-Go (GNG) condition, and four-position reaction times (4PRT). The battery was administered to 300 healthy participants aged between 14 and 89, and 3 groups of patients: 24 right brain-damaged; 21 left brain-damaged, and 19 degenerative cognitively impaired. We have developed specific norms for each task of the test battery: SRT, GNG, and 4PRT. Compared with healthy individuals, all groups obtained lower scores. More specifically, cognitively impaired patients obtained significantly longer RTs than healthy participants as well as unilateral brain-damaged patients. In the 4PRT task, right brain-damaged patients obtained a significantly left > right difference in RTs. In conclusion, the OORTT test battery proved to be a valuable tool which can be used in the clinical environment for cases of different attentional deficits after focal or degenerative brain damage.

Can the right hemisphere read? A behavioral and disconnectome study on implicit reading in a patient with pure alexia.

Patients with pure alexia have major difficulties in reading aloud. However, they often perform above chance level in reading tasks that do not require overt articulation of the target word - like lexical decision or semantic judgment - a phenomenon usually known as "implicit reading." There is no agreement in the literature on whether implicit reading should be attributed to relative sparing of some left hemisphere (LH) reading centers or rather to signs of compensatory endeavors by the right hemisphere (RH). We report the case of an 81-year-old patient (AA) with pure alexia due to a lesion involving the left occipital lobe and the temporal infero-mesial areas, as well as the posterior callosal pathways. Although AA's reading was severely impaired and proceeded letter by letter, she showed an above-chance-level performance for frequent concrete words in a tachistoscopic lexical decision task. A structural disconnectome analysis revealed that AA's lesion not only affected the left occipital cortex and the splenium: it also disconnected white-matter tracts meant to connect the visual word-form system to decision-related frontal areas within the LH. We suggest that the RH, rather than the LH, may be responsible for patient AA's implicit reading.

Phonological and surface dyslexia in individuals with brain tumors: Performance pre-, intra-, immediately post-surgery and at follow-up.

We address existing controversies regarding neuroanatomical substrates of reading-aloud processes according to the dual-route processing models, in this particular instance in a series of 49 individuals with brain tumors who performed several reading tasks of real-time neuropsychological testing during surgery (low- to high-grade cerebral neoplasms involving the left hemisphere). We explored how reading abilities in individuals with brain tumors evolve during and after surgery for a brain tumor, and we studied the reading performance in a sample of 33 individuals in a 4-month follow-up after surgery. Impaired reading performance was seen pre-surgery in 7 individuals with brain tumors, intra-surgery in 18 individuals, at immediate post-surgery testing in 26 individuals, and at follow-up in 5 individuals. We classified their reading disorders according to operational criteria for either phonological or surface dyslexia. Neuroimaging results are discussed within the theoretical framework of the dual-route model of reading. Lesion-mask subtraction analyses revealed that areas selectively related with phonological dyslexia were located-along with the left hemisphere dorsal stream-in the Rolandic operculum, the inferior frontal gyrus, the precentral gyrus, the supramarginal gyrus, the insula (and/or the underlying external capsule), and parts of the superior longitudinal fasciculus, whereas lesions related to surface dyslexia involved the ventral stream, that is, the left middle and inferior temporal gyrus and parts of the left inferior longitudinal fasciculus.

A Metabolic Imaging Study of Lexical and Phonological Naming Errors in Alzheimer Disease.

Patients with Alzheimer disease (AD) produce a variety of errors on confrontation naming that indicate multiple loci of impairment along the naming process in this disease. We correlated brain hypometabolism, measured with 18fluoro-deoxy-glucose positron emission tomography, with semantic and formal errors, as well as nonwords deriving from phonological errors produced in a picture-naming test by 63 patients with AD. Findings suggest that neurodegeneration leads to: (1) phonemic errors, by interfering with phonological short-term memory, or with control over retrieval of phonological or prearticulatory representations, within the left supramarginal gyrus; (2) semantic errors, by disrupting general semantic or visual-semantic representations at the level of the left posterior middle and inferior occipitotemporal cortex, respectively; (3) formal errors, by damaging the lexical-phonological output interface in the left mid-anterior segment of middle and superior temporal gyri. This topography of semantic-lexical-phonological steps of naming is in substantial agreement with dual-stream neurocognitive models of word generation.

Evaluating Semantic Knowledge Through a Semantic Association Task in Individuals With Dementia.

Conceptual knowledge is supported by multiple semantic systems that are specialized for the analysis of different properties associated with object concepts. Various types of semantic association between concrete concepts-categorical (CA), encyclopedic (EA), functional (FA), and visual-encyclopedic (VEA) associations-were tested through a new picture-to-picture matching task (semantic association task, SAT). Forty individuals with Alzheimer's disease (AD), 13 with behavioral variant of frontotemporal dementia (bv-FTD), 6 with primary progressive aphasia (PPA), and 37 healthy participants were tested with the SAT. Within-group comparisons highlighted a global impairment of all types of semantic association in bv-FTD individuals but a disproportionate impairment of EA and FA, with relative sparing of CA and VEA, in AD individuals. Single-case analyses detected dissociations in all dementia groups. Conceptual knowledge can be selectively impaired in various types of neurodegenerative disease on the basis of the specific cognitive process that is disrupted.

Correction to: The assessment of severe lexical disorders in Italian individuals with aphasia.

This article was published with incomplete Table 4. The Equivalent scores were missing during the submission. The correct Table is presented here.

The assessment of severe lexical disorders in Italian individuals with aphasia.

Tests and batteries used in the evaluation of language impairments are overly complex and often ineffective (too difficult) in the assessment of post-stroke patients affected by severe aphasia (global aphasia). The present study reports details on the construction and standardization of a new Italian battery of tasks, specifically designed to assess severe lexical disorders in acquired aphasia (Battery for the Assessment of Severe Acquired Lexical Damage in Italian, BASALDI). The battery is composed of a common set of 64 stimuli (concrete nouns), belonging to both living and non-living categories, and consists of four lexical tasks assessing picture naming, repetition, reading aloud, and oral comprehension. The item selection was based on word frequency, word length, and phonological-articulatory complexity, namely the presence of continuant vs. plosive phones, a variable that may interact with word production in case of severe language damage. Standardization (naming agreement) of a new set of 64 colored images and normative data on Italian healthy subjects pooled across homogenous subgroups for age, gender, and education are reported. Finally, for the four tasks, percentile ranks and z-scores were calculated from a pool of 92 left brain-damaged patients affected by aphasia of different types and severity. The battery allows a fine investigation of lexical disorders, being suitable for diagnostic assessment of mild-to-moderate and severe aphasic lexical deficits, detection of changes over time, and possible dissociations between tasks.

Verb and sentence processing patterns in healthy Italian participants: Insight from the Northwestern Assessment of Verbs and Sentences (NAVS).

We developed an Italian version of the Northwestern Assessment of Verbs and Sentences (NAVS, Thompson, 2011), a test assessing verb and sentence deficits typically found in aphasia, by focusing on verb-argument structure and syntactic complexity effects, rarely captured by standard language tests. Twenty-one young healthy individuals underwent a computerized experimental version of the NAVS, including three subtests assessing production/comprehension of verbs with different number (one, two, three) and type (obligatory or optional) of arguments, and two investigating production/comprehension of sentences with canonical/non-canonical word order. The number of verb arguments affected participants' reaction times (RTs) in verb naming and comprehension. Furthermore, verbs with optional arguments were processed faster than verbs with only obligatory arguments. Comprehension accuracy was lower for object-cleft vs. subject-cleft sentences. Object clefts and object relatives also elicited longer RTs than subject clefts and subject relatives, respectively. The study shows that the NAVS is sensitive to linguistic aspects of verb/sentence processing in Italian as in the English language. The study also highlights some differences between languages in the verb/sentence processing patterns of healthy individuals. Finally, the study contributes to the understanding of how information about verb-argument structure is represented and processed in healthy individuals, with reference to current models of verb processing.

Effects of Reading Proficiency and of Base and Whole-Word Frequency on Reading Noun- and Verb-Derived Words: An Eye-Tracking Study in Italian Primary School Children.

The aim of this study is to assess the role of readers' proficiency and of the base-word distributional properties on eye-movement behavior. Sixty-two typically developing children, attending 3rd, 4th, and 5th grade, were asked to read derived words in a sentence context. Target words were nouns derived from noun bases (e.g., umorista, 'humorist'), which in Italian are shared by few derived words, and nouns derived from verb bases (e.g., punizione, 'punishment'), which are shared by about 50 different inflected forms and several derived words. Data shows that base and word frequency affected first-fixation duration for nouns derived from noun bases, but in an opposite way: base frequency had a facilitative effect on first fixation, whereas word frequency exerted an inhibitory effect. These results were interpreted as a competition between early accessed base words (e.g., camino, chimney) and target words (e.g., caminetto, fireplace). For nouns derived from verb bases, an inhibitory base frequency effect but no word frequency effect was observed. These results suggest that syntactic context, calling for a noun in the target position, lead to an inhibitory effect when a verb base was detected, and made it difficult for readers to access the corresponding base+suffix combination (whole word) in the very early processing phases. Gaze duration was mainly affected by word frequency and length: for nouns derived from noun bases, this interaction was modulated by proficiency, as length effect was stronger for less proficient readers, while they were processing low-frequency words. For nouns derived from verb bases, though, all children, irrespective of their reading ability, showed sensitivity to the interaction within frequency of base+suffix combination (word frequency) and target length. Results of this study are consistent with those of other Italian studies that contrasted noun and verb processing, and confirm that distributional properties of morphemic constituents have a significant impact on the strategies used for processing morphologically complex words.