Executive dysfunction affects word list recall performance: Evidence from amyotrophic lateral sclerosis and other neurodegenerative diseases

The Rey Auditory Verbal Learning Test (RAVLT) is widely used in clinical practice to evaluate verbal episodic memory. While there is evidence that RAVLT performance can be influenced by executive dysfunction, the way executive disorders affect the serial position curve (SPC) has not been yet explored. To this aim, we analysed immediate and delayed recall performances of 13 non‐demented amyotrophic lateral sclerosis (ALS) patients with a specific mild executive dysfunction (ALSci) and compared their performances to those of 48 healthy controls (HC) and 13 cognitively normal patients with ALS. Moreover, to control for the impact of a severe dysexecutive syndrome and a genuine episodic memory deficit on the SPC, we enrolled 15 patients with a diagnosis of behavioural variant of frontotemporal dementia (bvFTD) and 18 patients with probable Alzheimer's disease (AD). Results documented that, compared to cognitively normal subjects, ALSci patients had a selective mid‐list impairment for immediate recall scores. The bvFTD group obtained low performances with a selectively increased forgetting rate for terminal items, whereas the AD group showed a disproportionately large memory loss on the primary and middle part of the SPC for immediate recall scores and were severely impaired in the delayed recall trial. These results suggested that subtle executive dysfunctions might influence the recall of mid‐list items, possibly reflecting deficiency in control strategies at retrieval of word lists, whereas severer dysexecutive syndrome might also affect the recall of terminal items possibly due to attention deficit or retroactive interference.     

Age-related trends in Stroop and conflicting motor response task findings.

Inhibition problems are reportedly at the heart of several childhood pathologies and learning disorders, but few instruments are available for their in-depth investigation. The main aim of the present study was to investigate the development of a capacity to inhibit automatic responses in young and middle childhood. For this purpose, 100 children between 6 and 11 years old were administered two tests that measure executive inhibition: an animal Stroop task (in a paper-and-pencil version of the computerized original proposed by Wright and colleagues in 2003) and a conflicting motor response task. Our results indicate that performance clearly improves in both tests during the course of a child's development and the data obtained with the paper-and-pencil animal Stroop task overlap with those obtained with the computerized version. When the task calls for a stronger inhibitory control (the incongruent situation in the Stroop task and in the opposite condition in the conflicting motor response test) the trend of the response times is less homogeneous, peaking in the youngest and oldest age brackets considered. The positivity and significance of the correlation coefficients between the two tests also suggest that the two measures are tapping cognitive abilities that are developing in a parallel fashion.     

Representational neglect for words as revealed by bisection tasks

In the present study, we showed that a representational disorder for words can dissociate from both representational neglect for objects and neglect dyslexia. This study involved 14 brain-damaged patients with left unilateral spatial neglect and a group of normal subjects. Patients were divided into four groups based on presence of left neglect dyslexia and representational neglect for non-verbal material, as evaluated by the Clock Drawing test. The patients were presented with bisection tasks for words and lines. The word bisection tasks (with words of five and seven letters) comprised the following: (1) representational bisection: the experimenter pronounced a word and then asked the patient to name the letter in the middle position; (2) visual bisection: same as (1) with stimuli presented visually; and (3) motor bisection: the patient was asked to cross out the letter in the middle position. The standard line bisection task was presented using lines of different length. Consistent with the literature, long lines were bisected to the right and short lines, rendered comparable in length to the words of the word bisection test, deviated to the left (crossover effect). Both patients and controls showed the same leftward bias on words in the visual and motor bisection conditions. A significant difference emerged between the groups only in the case of the representational bisection task, whereas the group exhibiting neglect dyslexia associated with representational neglect for objects showed a significant rightward bias, while the other three patient groups and the controls showed a leftward bisection bias. Neither the presence of neglect alone nor the presence of visual neglect dyslexia was sufficient to produce a specific disorder in mental imagery. These results demonstrate a specific representational neglect for words independent of both representational neglect and neglect dyslexia.     

Beyond the abstract—concrete dichotomy: Mode of acquisition,concreteness, imageability,familiarity, age of acquisition,context availability,and abstractness norms for a set of 417 Italian words

The main objective of this study is to investigate the abstract-concrete dichotomy by introducing a new variable: the mode of acquisition (MoA) of a concept. MoA refers to the way in which concepts are acquired: through experience, through language, or through both. We asked 250 participants to rate 417 words on seven dimensions: age of acquisition, concreteness, familiarity, context availability, imageability, abstractness, and MoA. The data were analyzed by considering MoA ratings and their relationship with the other psycholinguistic variables. Distributions for concreteness, abstractness, and MoA ratings indicate that they are qualitatively different. A partial correlation analysis revealed that MoA is an independent predictor of concreteness or abstractness, and a hierarchical multiple regression analysis confirmed MoA as being a valid predictor of abstractness. Strong correlations with measures for the English translation equivalents in the MRC database confirmed the reliability of our norms. The full database of MoA ratings and other psycholinguistic variables may be downloaded from http:// brm.psychonomic-journals.org/content/supplemental or www.abstract-project.eu.     

Newborns' face recognition is based on spatial frequencies below 0.5 cycles per degree

A critical question in Cognitive Science concerns how knowledge of specific domains emerges during development. Here we examined how limitations of the visual system during the first days of life may shape subsequent development of face processing abilities. By manipulating the bands of spatial frequencies of face images, we investigated what is the nature of the visual information that newborn infants rely on to perform face recognition. Newborns were able to extract from a face the visual information lying from 0 to 1 cpd (Experiment 1), but only a narrower 0-0.5 cpd spatial frequency range was successful to accomplish face recognition (Experiment 2). These results provide the first empirical support of a low spatial frequency advantage in individual face recognition at birth and suggest that early in life low-level, non-specific perceptual constraints affect the development of the face processing system.     

Newborns' face recognition over changes in viewpoint

The study investigated the origins of the ability to recognize faces despite rotations in depth. Four experiments are reported that tested, using the habituation technique, whether 1-to-3-day-old infants are able to recognize the invariant aspects of a face over changes in viewpoint. Newborns failed to recognize facial perceptual invariances between profile and full-face poses (Experiment 1), and profile and 3/4 poses (Experiment 3). Conversely, newborns recognized the identity of a face through full-face and 3/4 poses (Experiment 2). This result cannot be explained as a consequence of newborns' inability to discriminate between the full-face and 3/4 points of view (Experiment 4). Overall, evidence was provided that newborns are able to derive a representation of an unfamiliar face that is resilient to a certain degree of rotation in depth, from full-face to 3/4 and vice versa.     

Effect of partial occlusion on newborns' face preference and recognition

Many studies have shown that newborns prefer (e.g. Goren, Sarty & Wu, 1975; Valenza, Simion, Macchi Cassia & Umiltà, 1996) and recognize (e.g. Bushnell, Say & Mullin, 1989; Pascalis & de Schonen, 1994) faces. However, it is not known whether, at birth, faces are still preferred and recognized when some of their parts are not visible because hindered by other configurations, that is when faces are partly occluded. Also, it is not known whether newborns' preference for an upright over an inverted face and newborns' face recognition are differentially affected depending on the salience of the occluded face features. Seventy-seven newborns (mean age of 43.5 hrs) were tested using the preferential looking (Experiment 1) and the habituation techniques (Experiment 2). Results demonstrated that newborns prefer and recognize occluded faces even if some portions of them are not available, at least when the hindered features are not salient. On the contrary, these abilities are affected by obscuring high salience facial features (i.e. eyes). However, while in the case of face detection, eyes occlusion completely prevented newborns' face detection, in the case of face recognition an analogous stimulus manipulation heavily impaired, but did not totally preclude, newborns' recognition performance. The data collected improve our comprehension of newborns' way of processing and encoding information to detect and recognize faces.