- 351-217943600
J. Frederico Marques
Universidade de Lisboa, Faculdade de Psicologia, Faculty Member
Visual complexity is a quality of objects that can be understood in terms of information richness: The more complex an object is, the more information it contains. Visual complexity is therefore likely to have a considerable impact on... more
Visual complexity is a quality of objects that can be understood in terms of information richness: The more complex an object is, the more information it contains. Visual complexity is therefore likely to have a considerable impact on visual object processing. Here we demonstrate that visual complexity does indeed affect visual object processing but that it exerts different effects depending on task requirements. In tasks that require little differentiation among objects (superordinate categorization), reaction times decrease linearly as a function of increasing visual complexity. In tasks that require more differentiation (difficult object decision), complexity exerts the opposite effect. We argue that this dynamic interplay between visual complexity and object individuation can be explained by assuming that complexity affects two operations in visual object recognition differentially: When perceptual representations are formed it exerts a negative effect because representations of complex objects are harder to assemble than representations of less complex objects, but once formed, it exerts a positive effect because complex objects—due to their information richness—activate fewer candid- ate representations in visual long-term memory that need to be differentiated in the recognition process.
Recent studies have shown that members of superordinate concepts share less features than members of basic level concepts. An artificial neural network model was implemented to evaluate if feature sharedness could distinguish between... more
Recent studies have shown that members of superordinate concepts share less features than members of basic level concepts. An artificial neural network model was implemented to evaluate if feature sharedness could distinguish between these two types of concepts and if lesioning the network would particularly affect less shared features and superordinate categorization. The model was successful in the semantic categorization test, supporting the idea that superordinate and basic level concepts can be distinguished on the basis of feature sharedness. In contrast, lesion results proved that the model structure was not adequate to evaluate the relation between feature sharedness, processing requirements and patient performance. Limitations and future directions for modeling semantic memory and for semantic computing are discussed.
Processing within the dorsal visual stream subserves object-directed action, whereas visual object recognition is mediated by the ventral visual stream. Recent findings suggest that the computations performed by the dorsal stream can... more
Processing within the dorsal visual stream subserves object-directed action, whereas visual object recognition is mediated by the ventral visual stream. Recent findings suggest that the computations performed by the dorsal stream can nevertheless influence object recognition. Little is known, however, about the type of dorsal stream information that is available to assist in object recognition. Here, we present a series of experiments that explored different psychophysical manipulations known to bias the processing of a stimulus toward the dorsal visual stream in order to isolate its contribution to object recognition. We show that elongated-shaped stimuli, regardless of their semantic category and familiarity, when processed by the dorsal stream, elicit visuomotor grasp-related information that affects how we categorize manipulable objects. Elongated stimuli may reduce ambiguity during grasp preparation by providing a coarse cue to hand shaping and orientation that is sufficient to support action planning. We propose that this dorsal-stream-based analysis of elongation along a principal axis is the basis for how the dorsal visual object processing stream can affect categorization of manipulable objects.
The present study directly evaluates the impact of feature sharedness on the differences between superordinate and basic- level concepts observed in aphasia patients due to fronto- temporal stroke. In particular, it was evaluated if... more
The present study directly evaluates the impact of feature sharedness on the differences between superordinate and basic- level concepts observed in aphasia patients due to fronto- temporal stroke. In particular, it was evaluated if feature shared- ness composition explains the superordinate deficits observed in these patients. For this purpose we studied 6 stroke aphasia pa- tients and 12 matched controls using a sentence verification task in which feature sharedness (more vs. less shared) and concept level (basic level vs. superordinate) were orthogonally manipu- lated. The results showed that sentences involving more shared features were processed faster and more accurately than sentences involving less shared features. This difference was particularly relevant in the processing of superordinate concepts, and was exacerbated for patients in relation to healthy controls. These findings suggest that deficits in executive function especially impact the processing of less shared features leading to superor- dinate deficits in stroke aphasia.
The present study directly evaluates the impact of feature sharedness on the differences between superordinate and basic- level concepts observed in aphasia patients due to fronto- temporal stroke. In particular, it was evaluated if... more
The present study directly evaluates the impact of feature sharedness on the differences between superordinate and basic- level concepts observed in aphasia patients due to fronto- temporal stroke. In particular, it was evaluated if feature shared- ness composition explains the superordinate deficits observed in these patients. For this purpose we studied 6 stroke aphasia pa- tients and 12 matched controls using a sentence verification task in which feature sharedness (more vs. less shared) and concept level (basic level vs. superordinate) were orthogonally manipu- lated. The results showed that sentences involving more shared features were processed faster and more accurately than sentences involving less shared features. This difference was particularly relevant in the processing of superordinate concepts, and was exacerbated for patients in relation to healthy controls. These findings suggest that deficits in executive function especially impact the processing of less shared features leading to superor- dinate deficits in stroke aphasia.
To interpret a sentence, the reader must not only process the linguistic input, but many times has also to draw inferences about what is implicitly stated. In some cases, the generation and integration of inferred information may lead to... more
To interpret a sentence, the reader must not only process the linguistic input, but many times has also to draw inferences about what is implicitly stated. In some cases, the generation and integration of inferred information may lead to semantic illusions. In these sentences, subjects fail to detect errors such as in “It was two animals of each kind that Moses took on the ark” despite knowing that the correct answer is Noah, not Moses. The relative inability to notice these errors raises questions about how people establish and integrate inferences and which conditions improve error detection. To unravel the neural processes un- derlying inference and error detection in language comprehension, we carried out an fMRI study in which participants read sentences containing true or false statements. The false statements either took the form of more obvious (i.e., clearly false) or subtle (i.e., semantic illusions) inconsistent relations. Participants had to decide if each statement was true or false. Processing semantic illusions relative to true and clearly false sentences significantly engaged the right inferior parietal lobule, suggesting higher demands in establishing coherence. Successful versus unsuccessful error detection revealed a network of regions, includ- ing right dorsolateral prefrontal cortex, orbitofrontal, insula/putamen and anterior cingulate cortex. Such ac- tivation was significantly correlated with overall response accuracy to the illusions. These results suggest that to detect the semantic conflict, people must inhibit the tendency to draw pragmatic inferences. These find- ings demonstrate that fronto-parietal areas are involved in inference and inhibition processes necessary for establishing semantic coherence.
In the present studies, we evaluated the contribu- tions of language and sensorimotor information to the rep- resentation of abstract and concrete words and the possibility that the organizations of the two types of con- cepts follow... more
In the present studies, we evaluated the contribu- tions of language and sensorimotor information to the rep- resentation of abstract and concrete words and the possibility that the organizations of the two types of con- cepts follow different organizational principles: association, for abstract concepts, and semantic similarity, for concrete concepts. In Study 1, we examined the two strongest asso- ciates of concrete and abstract words from published free association norms. Study 2 then extended this analysis to individual data collected with a free association task. Lan- guage associations were more important for abstract than for concrete words, but for sensorimotor information no differ- ences were observed between the two types of concepts. Also, no clear evidence was found for different qualitative organizational principles for abstract and concrete concepts. Multiple representational systems thus seem to be engaged in the conceptual processing of abstract and concrete con- cepts, while it remains to be investigated whether their representations follow different organizational principles.
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Data from neuropsychological research suggest that categorizing objects at different levels of specificity requires different cognitive and neural processes. This short paper presents and discusses a theoretical hypothesis for this... more
Data from neuropsychological research suggest that categorizing objects at different levels of specificity requires different cognitive and neural processes. This short paper presents and discusses a theoretical hypothesis for this organization in terms of feature sharedness. It is proposed that superordinate concepts involve a larger absolute number of exemplars that share a particular feature, thus making them more resistant to damage than basic level concepts (i.e. superordinate advantage). Simultaneously, in relative terms, features are less shared overall by superordinate members than by basic level members, which imply higher executive requirements and can conversely lead to superordinate deficits. This hypothesis is discussed in relation to behavioral data from semantic dementia and stroke aphasia patients and fMRI data from healthy subjects that support the role of feature sharedness in the hierarchical organization of semantic knowledge.
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The present research evaluates the sensitivity and salience of form-function correlations in contrast with other types of feature correlations (function-function, form-form) in adults and using real object features (from tools and... more
The present research evaluates the sensitivity and salience of form-function correlations in contrast with other types of feature correlations (function-function, form-form) in adults and using real object features (from tools and utensils). In Experiment 1 participants judged the relation between form and function features of tools. In Experiment 2 participants were asked to generate a second feature related to a given form or function feature. In Experiment 3 participants were asked to make a lexical decision in which form and function features were used as primes and targets. Results showed that even though participants were sensitive to form-function correlations, these were not particularly salient when compared with other feature type correlations, notably function-function correlations. Our data underline the overall importance of function information to object representation and the impact of statistical co-occurrence of features when processing object features.
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We evaluated the contribution of four structural dimensions (object parts, internal details, objects contours, and variability of the representation), as a possible source of categorical processing differences and category-specific... more
We evaluated the contribution of four structural dimensions (object parts, internal details, objects contours, and variability of the representation), as a possible source of categorical processing differences and category-specific deficits. Importantly, these dimensions aggregate 22 different structural measures that have been proposed to describe the Snodgrass and Vanderwart (1980) picture set. Study 1 analysed the differences between the four dimensions across domains and categories. Study 2 investigated how these dimensions may contribute to the performance of two patients with category-specific deficits that have been reported previously in the literature (Farah et al., 1991). The results showed that living things were structurally more complex than non-living things, scoring higher in object parts and object contours. Regarding the variability of the representation, living things did not show much within-item diversity but did show more contour overlap and less visual similarity, the latter two qualities of living things being detrimental to object processing in a naming task. Parts, contours and variability of the representation also differentiated animals, fruits and vegetables and, to a certain degree, non-living things: animals had more parts, fruits had more object contours and non-living things had a lower variability of the representation (which was especially related to higher within-item diversity and lower contour overlap). The same three dimensions predicted patient performance. However, when structural dimensions were considered together with domain (living/nonliving) and concept familiarity, only variability of the representation contributed significantly to patient performance.
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Research on the processing of objects at different hierarchical levels has suggested that understanding superordinate concepts (e.g. fruit), relative to basic level concepts (e.g. apple), requires greater semantic control demands. Yet, it... more
Research on the processing of objects at different hierarchical levels has suggested that understanding superordinate concepts (e.g. fruit), relative to basic level concepts (e.g. apple), requires greater semantic control demands. Yet, it is unclear which factors underlie this difference in executive processing. We built on previous research showing that superordinate concepts have less shared features among their members and therefore may involve higher semantic control requirements. To test this hypothesis, we developed an fMRI study in which we orthogonally manipulated feature sharedness (more shared vs. less shared) and concept level (superordinate vs. basic) in a sentence verification task. Sentences involving less shared features, relative to more shared features, significantly engaged the L lateral PFC. Importantly, sentences that included superordinate concepts, relative to those with basic level concepts, also revealed a stronger response in L lateral PFC, along with posterior temporal gyrus activation. There was also a significant interaction between feature sharedness and concept level in several PFC regions and L posterior temporal areas. The results suggest that relative to basic level concepts, processing superordinate concepts requires extra semantic control in L lateral PFC to coordinate information that is less shared by other members of the category level. These findings demonstrate that feature sharedness impacts the neural basis of semantic knowledge, and is a critical dimension in the processing of superordinate concepts.
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The goal of this paper is to examine the hierarchical organization of semantic memory considering the nature of superordinate categories, their characteristics and their associate main effects: the basic-level advantage in healthy... more
The goal of this paper is to examine the hierarchical organization of semantic memory considering the nature of superordinate categories, their characteristics and their associate main effects: the basic-level advantage in healthy individuals and the pathological phenomena of the superordinate advantage and of the superordinate deficit. The first two effects are analyzed in turn, taking into account the models proposed for their explanation and their limitations, and distinguishing Rogers and Patterson (2007) model as the first one to offer a satisfactory explanation for these effects. I then analyze the more recent effect of the superordinate deficit and its’ explanation in terms of executive function. In a final section, I propose a revision of the framework of Rogers and Patterson’s (2007) model regarding the nature of superordinate categories and I show how this revised model can explain all three effects.
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The present paper evaluated the nature of the organization of 22 structural measures of object pictures from the Snodgrass and Vanderwart (1980) picture set (Study 1), and their contribution to object decision and to object naming... more
The present paper evaluated the nature of the organization of 22 structural measures of object pictures from the Snodgrass and Vanderwart (1980) picture set (Study 1), and their contribution to object decision and to object naming latencies (Studies 2 and 3). Study 1 employed a principal components analysis and provided evidence of four underlying components: “Object parts”, “internal details”, “object contours”, and “variability of the representation”. Study 2 examined the contribution of these components to object decision and object naming and highlighted variability of the representation and internal details as the most relevant indexes of structural similarity. Study 3 investigated the interactions between these structural components and lexical frequency. Main results showed an interaction effect between variability of the representation and lexical frequency and other effects associated to internal details. Implications for the concept of structural similarity and for object recognition are discussed from a continuous and cascade processing perspective.
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OBJECTIVE: The principal aim of the present study was to evaluate the impact of semantic relevance and feature type on the ability to name from definition. METHOD: Thirty-two normal young subjects (Study 1) and 20 probable Alzheimer's... more
OBJECTIVE: The principal aim of the present study was to evaluate the impact of semantic relevance and feature type on the ability to name from definition. METHOD: Thirty-two normal young subjects (Study 1) and 20 probable Alzheimer's disease patients (pAD) with 20 matched older controls (Study 2) were tested with verbal definitions consisting of 4 features, combining feature type (sensory vs. nonsensory) and semantic relevance (high vs. low). The subjects were asked to provide a name corresponding to the definition and to select which individual features they considered most important in justifying their answer. RESULTS: Feature selection results showed that high-relevance features first (d = 2.13 in Study 1; d = 1.44 in Study 2) and nonsensory features second (d = 0.81 in Study 1; d = 0.36 in Study 2) were the main dimensions driving correct performance. Overall, naming performance was affected by the age of acquisition (AoA) of the concept, and differences between the groups in all measures were mainly quantitative. CONCLUSIONS: These findings suggest that semantic relevance and feature type are important feature dimensions in conceptual representation and in conceptual access and retrieval. Moreover, results suggest that the former dimension may be more important than the latter, at least in the case of naming from definition. Finally, these results extend previous findings with other tasks, supporting the importance of AoA for correct performance and suggesting that the poorer performance of pAD patients on semantic tasks may represent an exaggeration of difficulties found also in normal older subjects.
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The present paper evaluates the effect of visual deprivation on the organization and retrieval of conceptual knowledge. The experimental study used the release from proactive interference (PI-release) paradigm. Early onset blind (EOB) and... more
The present paper evaluates the effect of visual deprivation on the organization and retrieval of conceptual knowledge. The experimental study used the release from proactive interference (PI-release) paradigm. Early onset blind (EOB) and sighted (S) subjects were tested with this task and additional visual and nonvisual property retrieval cues. PI-release results showed that the visual cue was less effective for EOB individuals than for S individuals, whereas the nonvisual cue was similarly effective for EOB individuals and S individuals. Results support a grounded view of cognition where the organization of conceptual knowledge depends on the role that sensory and motor channels play in its acquisition.
Research Interests: Psychology, Cognitive Science, Experimental Psychology, Perception, Auditory Perception, and 18 moreCognition, Blindness, Visual perception, Vision, Humans, Cues, Concept Formation, Female, Male, Reaction Time, Verbal behavior, Concept, Visual Cues, Adult, Sensory Deprivation, Proactive Interference, Case Control Studies, and Neuropsychological Tests
The inquiry on the nature of truth in language comprehension has a long history of opposite perspectives. These perspectives either consider that there are qualitative differences in the processing of true and false statements, or that... more
The inquiry on the nature of truth in language comprehension has a long history of opposite perspectives. These perspectives either consider that there are qualitative differences in the processing of true and false statements, or that these processes are fundamentally the same and only differ in quantitative terms. The present study evaluated the processing nature of true and false statements in terms of patterns of brain activity using event-related functional-Magnetic-Resonance-Imaging (fMRI). We show that when true and false concept-feature statements are controlled for relation strength/ambiguity, their processing is associated to qualitatively different processes. Verifying true statements activates the left inferior parietal cortex and the caudate nucleus, a neural correlate compatible with an extended search and matching process for particular stored information. In contrast, verifying false statements activates the fronto-polar cortex and is compatible with a reasoning process of finding and evaluating a contradiction between the sentence information and stored knowledge.
Research Interests: Cognitive Science, Magnetic Resonance Imaging, Semantic Memory, Meaning, Language, and 20 moreLanguage Comprehension, Brain Mapping, Evoked Potentials, Humans, Caudate Nucleus, Cerebral Cortex, Comprehension, Concept Formation, Female, Male, Search and Matching, Cortex, Young Adult, Cognitive Process, Cognitive processes, Adult, Parietal Lobe, Neurosciences, Frontal Lobe, and Functional Laterality
The organization and representation of conceptual knowledge in the brain remains a controversial issue in terms of both neuropsychological and imaging evidence. We report the results of a functional magnetic resonance study in which the... more
The organization and representation of conceptual knowledge in the brain remains a controversial issue in terms of both neuropsychological and imaging evidence. We report the results of a functional magnetic resonance study in which the role of the most debated dimensions (domain and feature type) was evaluated through a concept-feature verification task. The scope of the task was to eliminate serious methodological concerns that weighed down previous imaging research in this area, and to allow more definitive conclusions regarding the specific contribution of these dimensions. The results show differential patterns of brain activity according to feature type (both motion and visual form/surface features) but not according to concept domain (living vs. nonliving things). These findings are in accord with a modality-specific account of conceptual knowledge organization in the brain, in which specific kinds of features (e.g. form, color, motion, etc) have differential importance for representing different concepts.
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The deterioration of semantic memory usually proceeds from more specific to more general superordinate categories, although rarer cases of superordinate knowledge impairment have also been reported. The nature of superordinate knowledge... more
The deterioration of semantic memory usually proceeds from more specific to more general superordinate categories, although rarer cases of superordinate knowledge impairment have also been reported. The nature of superordinate knowledge and the explanation of these two semantic impairments were evaluated from the analysis of superordinate and basic-level feature norms. The results show that, in comparison to basic-level concepts, superordinate concepts are not generally less informative and have similar feature distinctiveness and proportion of individual sensory features, but their features are less shared by their members. Results are in accord with explanations based on feature connection weights and/or concept confusability for the superordinate advantage cases. Results especially support an explanation for superordinate impairments in terms of higher semantic control requirements as related to features being less shared between concept members. Implications for patients with semantic impairments are also discussed.
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This study examines how numerical intuition for prices in euros and in the Portuguese currency escudos developed in Portugal after the euro changeover. Estimates of prices of 40 different products were collected in the two currencies and... more
This study examines how numerical intuition for prices in euros and in the Portuguese currency escudos developed in Portugal after the euro changeover. Estimates of prices of 40 different products were collected in the two currencies and at four different times from November 2001 to April 2004. The results regarding price estimates in euros were more in accordance with a relearning hypothesis considering that price estimates become progressively more accurate by a process that is related to purchase frequency. It was also suggested that this is a very slow process and that prices in the former currency are not simply forgotten. On the contrary, the escudos remained a general benchmark for an extended period. The results regarding estimated price intuition and use of intuition in estimating prices are also consistent with a slow adaptation process. Implications for future euro changeovers are discussed
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The main objective of this study is to report rated age of acquisition (AoA) norms for 834 nouns in Portuguese (European). AoA ratings were collected on a 7 point scale, generally following Gilhooly and Logie (1980) procedure with an 8... more
The main objective of this study is to report rated age of acquisition (AoA) norms for 834 nouns in Portuguese (European). AoA ratings were collected on a 7 point scale, generally following Gilhooly and Logie (1980) procedure with an 8 extra point for "don't know the word" answers. Results were analyzed considering AoA ratings and their standard deviations and considering the relationship between AoA ratings and other psycholinguistic variables (imageability, familiarity, written word frequency, concreteness, number of syllables and number of words). AoA ratings and their standard deviations were significantly and positively correlated, with early acquired word ratings showing higher agreement. Correlation and multiple regression analyses confirmed the major contribution of imageability and familiarity to AoA ratings obtained in other languages. The full database of AoA ratings and other psycholinguistic variables may be downloaded from www.psychonomic.org/archive or www.fpce.ul.pt/pessoal/ulfpfred/aoa.htm.
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The present article reviews the case for multiple systems in semantic memory and empirically evaluates a multiple semantics proposal based on sensory modalities. In the experiments, a conceptual switching cost paradigm was used (Pecher,... more
The present article reviews the case for multiple systems in semantic memory and empirically evaluates a multiple semantics proposal based on sensory modalities. In the experiments, a conceptual switching cost paradigm was used (Pecher, Zeelenberg, & Barsalou, 2003), in which participants verified properties for concepts and verification time was compared for target trials (e.g., a dog can bark) that were preceded by context trials of either the same or a different modality (e.g., a bee can buzz or a horse can have spots). Experiment 1 involved a modality switch while controlling for the concept's category and demonstrated that when modalities were switched, a processing cost was incurred that could not be attributed to the latter dimension. Experiment 2 further supported this conclusion by showing that, in a reverse situation, the cost incurred when category was switched was at least smaller. The results are discussed by considering possible alternative amodal explanations and other data that have shown the influence of sensory information in conceptual processing.
Research Interests: Psychology, Cognitive Science, Semantics, Auditory Perception, Cognition, and 19 morePsycholinguistics, Visual perception, Attention, Semantic Memory, Reading, Language, Adolescent, Humans, Touch, Comprehension, Concept Formation, Female, Male, Reaction Time, Adult, Empirical Evaluation, Reversal Learning, Neurosciences, and Switching Cost
The present study explores the structure of moviegoers knowledge about actors and actresses considered as categories of semantic knowledge. For this purpose, participants generated either names of actors or names of actresses and, in a... more
The present study explores the structure of moviegoers knowledge about actors and actresses considered as categories of semantic knowledge. For this purpose, participants generated either names of actors or names of actresses and, in a second phase of the experiment, judged their responses in terms of aesthetic preference and frequency of instantiation. Both categories exhibited a graded structure in terms of typicality but while frequency of instantiation was the strongest response determinant for actresses, aesthetic preference was the strongest response determinant for actors. Moviegoing frequency was positively related to the number of names produced for actors but not for actresses. Main conclusions suggest that actresses and actors are relevant semantic categories for moviegoers. Possible factors for differences between the two categories are also discussed.
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The present paper evaluates the contribution of feature type and feature distinctiveness to naming of living and nonliving things using a naming from definition task. Normal subjects read verbal descriptions containing features varying in... more
The present paper evaluates the contribution of feature type and feature distinctiveness to naming of living and nonliving things using a naming from definition task. Normal subjects read verbal descriptions containing features varying in type (i.e., sensory vs. functional) and distinctiveness (i.e., distinct vs. shared) and were asked to name the concept described and to select the three features that most contributed to their answer. Main results showed that sensory features were selected more often than functional features to support naming living things and that, independent of feature type, more distinct features were selected to support naming more often than shared features. Results are discussed considering the implications for understanding naming and for neuropsychological evaluation.
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Cortex Forum Discussion Paper (no abstract).
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Este estudo apresenta dados normativos de imagética (imagery) e concreteza (concreteness) para controlo e manipulação de substantivos comuns em Portugal. Medidas de imagética e concreteza foram recolhidas e são apresentadas para um total... more
Este estudo apresenta dados normativos de imagética (imagery) e concreteza (concreteness) para controlo e manipulação de substantivos comuns em Portugal. Medidas de imagética e concreteza foram recolhidas e são apresentadas para um total de 250 substantivos comuns.
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Este estudo apresenta dados normativos de familiaridade para utilização enquanto base para controlo e manipulação de substantivos comuns em Portugal. Medidas familiaridade com o referente e com o significado (Larochelle & Saumier, 1993)... more
Este estudo apresenta dados normativos de familiaridade para utilização enquanto base para controlo e manipulação de substantivos comuns em Portugal. Medidas familiaridade com o referente e com o significado (Larochelle & Saumier, 1993) foram recolhidas em dois momentos, num primeiro caso englobando apenas substantivos concretos (n=320) e num segundo momento englobando tanto substantivos concretos como abstractos (n=219). As normas são apresentadas para um total de 459 palavras diferentes.
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This article examines how numerical intuition for prices develops after a major change in currency. University students in Portugal (Study 1) and Austria (Study 2) made price estimates for 40 different items from November 2001 to June... more
This article examines how numerical intuition for prices develops after a major change in currency. University students in Portugal (Study 1) and Austria (Study 2) made price estimates for 40 different items from November 2001 to June 2002, surrounding the time at which these countries switched to the euro. Overall results are more in accordance with a relearning hypothesis, considering that price estimates become progressively more accurate by a process that is related to buying frequency and, hence, is faster for frequently bought items. An alternative global rescaling hypothesis received mixed support. Results also suggest that price estimations in euros have not yet reached a level of accuracy comparable with estimations in the former national currency.
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Cortex Forum Discussion Paper (no abstract)
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The present paper evaluates different hypotheses for explaining the living/nonliving things dissociation phenomenon in terms of feature type, considering the role of this dimension in the organization of conceptual semantic... more
The present paper evaluates different hypotheses for explaining the living/nonliving things dissociation phenomenon in terms of feature type, considering the role of this dimension in the organization of conceptual semantic representations and in the activation of name representations. For this purpose we used Sloman and associates' (Memory and Cognition 27(3) (1999) 526; Cognitive Science 22(2) (1998) 189) name centrality and conceptual centrality tasks and asked subjects to judge functional and perceptual/visual features of living and nonliving items. Conceptual centrality results are more in accordance with a "single feature-domain connection hypothesis" where visual features are more important than functional features for the representation of living things and no feature type advantage is found for nonliving things. Name centrality results show that functional features are more important than sensory/visual features overall, a result that is not predicted by any of the hypotheses considered. The fact that the two judgments diverge emphasizes their importance for evaluating the role of feature type in the living/nonliving dissociation. Implications for explaining this phenomenon are also discussed.
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The present paper contrasted categorical and featural hypotheses of semantic memory organisation in relation to the living/nonliving things dissociation phenomenon. In the three experiments reported, normal subjects decided if word pairs... more
The present paper contrasted categorical and featural hypotheses of semantic memory organisation in relation to the living/nonliving things dissociation phenomenon. In the three experiments reported, normal subjects decided if word pairs representing living, nonliving, or both (mixed pairs) shared a particular perceptual (i.e., four legs, size, and hardness) or functional attribute (i.e., dangerousness, speed, and usefulness). The overall pattern of results is more in accordance with a general featural perspective and also emphasises the role of functional attributes. Both a categorical perspective and an attribute-category connection hypothesis have more difficulties in explaining the observed data. Implications for the study of semantic memory organisation and for the explanation of living/nonliving things dissociation cases are also considered.
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The present paper examines the ability to evaluate prices in a familiar currency (French Francs, Portuguese Escudos or Irish Punt) and in an unfamiliar currency (Euro). Participants evaluated prices for different items either by selecting... more
The present paper examines the ability to evaluate prices in a familiar currency (French Francs, Portuguese Escudos or Irish Punt) and in an unfamiliar currency (Euro). Participants evaluated prices for different items either by selecting the most appropriate price from a set of alternatives (in a timed or not timed version) or by directly producing a price estimate for each item. The results followed Weber’s law: the standard deviation of estimated prices was proportional to their mean. The Weber fraction was stable for the familiar currency in different countries, but was significantly higher for the unfamiliar currency. We suggest that price estimation relies on a learned mapping between items and their prices as represented by distributions of activation on an internal number line. The observed Weber fraction reflects the degree of expertise with a given currency as well as a minimal variability intrinsic to the number line itself.
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The present paper evaluated categorical and featural proposals of memory organisation, for explaining the living/nonliving things dissociation observed in semantic memory. The experimental study used the Release from Proactive... more
The present paper evaluated categorical and featural proposals of memory organisation, for explaining the living/nonliving things dissociation observed in semantic memory. The experimental study used the Release from Proactive Interference (PI-release) paradigm. Normal subjects were tested with this task using word vs. picture stimuli in a standard taxonomical PI-release condition (i.e., nonliving to living things) and in a cue condition with attributes that run opposite to the taxonomical shift. Experiments 1 and 2 cued functional attributes (means of transportation; dangerousness), and experiments 3 and 4 cued perceptual attributes (size; number of legs). The overall pattern of PI-release emphasizes the role of functional attributes and the role of structural processing to semantic processing. Implications for the different proposals presented, including possible alternative accounts of the results, are also discussed.
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Reviews some of the changes that the introduction of new currency—the euro—will bring to everyday behavior from the point of view of the psychological literature on numerical cognition. Problems that can be foreseen converting and using... more
Reviews some of the changes that the introduction of new currency—the euro—will bring to everyday behavior from the point of view of the psychological literature on numerical cognition. Problems that can be foreseen converting and using the euro are reviewed including changes in terms of language (i.e., money labels and its lexicosyntactic structure) and price comparison. Possible answers to some of these problems are presented, considering the numerical cognition literature and several widely reported effects (e.g., the problem size/difficulty effect, symbolic distance effect). New opportunities for research in this domain both within countries and across countries are also discussed.
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Higher education selection procedures in Portugal are presented and examined from the point of view of their relatedness and the predictive validity to academic performance in the first year of higher education. Data collected from 1989... more
Higher education selection procedures in Portugal are presented and examined from the point of view of their relatedness and the predictive validity to academic performance in the first year of higher education. Data collected from 1989 to 1992 on freshmen samples at the Faculty of Psychology and Education of the University of Lisbon showed that the high school record relates more consistently to academic performance (grade point average and number of courses completed) than entrance examinations (national examination and university examinations), for which the pattern varies across groups. Technical aspects and the social implications of selection practices are discussed.