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Pre-attentive detection of motion direction changes in normal aging

Laura Lorenzo-López, Elena Amenedo, Paula Pazo-Alvarez, Fernando Cadaveira
2004 NeuroReport  
E¡ects of normal aging on pre-attentive detection of changes in motion direction were evaluated. Young, middle-aged, and older subjects performed a visual central task while standard and deviant gratings varying in motion direction were presented outside the focus of attention. A greater negativity in the event-related potentials (ERPs) to deviants was observed in all groups at posterior sites within the N2 latency range. Visual mismatch negativity (vMMN) reached its peak between145 and165 ms
more » ... respective of age. However, signi¢cant age-related changes observed in vMMN mean amplitude may suggest that the pre-attentive visual detection become less e⁄cient in older subjects. This could lead to age-related de¢cits in switching attention to potentially salient visual changes. NeuroReport 15:2633^2636 c 2004 Lippincott Williams & Wilkins.
doi:10.1097/00001756-200412030-00015 pmid:15570167 fatcat:xc6akiuktvab5i3s25dzk5kppu

Vertical asymmetries in pre-attentive detection of changes in motion direction

Elena Amenedo, Paula Pazo-Alvarez, Fernando Cadaveira
2007 International Journal of Psychophysiology  
Stimulus localization affects visual motion processing. Vertical asymmetries favouring lower visual field have been reported in event-related potentials (ERPs) and behavioural studies under different attention conditions. However, there are no studies examining such asymmetries to nonattended motion changes. The present study investigated whether the asymmetry in processing information from the upper and lower visual fields also affects the automatic detection of motion-direction changes as
more » ... xed by visual Mismatch Negativity (vMMN). We recorded vMMN to changes in sinusoidal gratings differing in motion direction presented in the periphery of visual field in three different locations: upper and lower (ULVF), upper (UVF) and lower (LVF) along the vertical meridian. The N2 component elicited to peripheral motion presented lower amplitudes when the UVF was stimulated. The vMMN elicited to infrequent motion-direction changes was present in all stimulation conditions. However, it was reduced to UVF stimulation. These results suggest that the visual system automatically detects motion-direction changes presented at both upper-lower visual fields; however they also indicate that the process is favoured when stimuli are presented in the LVF alone.
doi:10.1016/j.ijpsycho.2007.02.001 pmid:17343941 fatcat:rtnl27qfifhgxjjzo7xdh2kd6u

Attentional Modulation of Change Detection ERP Components by Peripheral Retro-Cueing

Paula Pazo-Álvarez, Adriana Roca-Fernández, Francisco-Javier Gutiérrez-Domínguez, Elena Amenedo
2017 Frontiers in Human Neuroscience  
Change detection is essential for visual perception and performance in our environment. However, observers often miss changes that should be easily noticed. A failure in any of the processes involved in conscious detection (encoding the pre-change display, maintenance of that information within working memory, and comparison of the pre and post change displays) can lead to change blindness. Given that unnoticed visual changes in a scene can be easily detected once attention is drawn to them, it
more » ... has been suggested that attention plays an important role on visual awareness. In the present study, we used behavioral and electrophysiological (ERPs) measures to study whether the manipulation of retrospective spatial attention affects performance and modulates brain activity related to the awareness of a change. To that end, exogenous peripheral cues were presented during the delay period (retro-cues) between the first and the second array using a oneshot change detection task. Awareness of a change was associated with a posterior negative amplitude shift around 228-292 ms ("Visual Awareness Negativity"), which was independent of retrospective spatial attention, as it was elicited to both validly and invalidly cued change trials. Change detection was also associated with a larger positive deflection around 420-580 ms ("Late Positivity"), but only when the peripheral retrocues correctly predicted the change. Present results confirm that the early and late ERP components related to change detection can be functionally dissociated through manipulations of exogenous retro-cueing using a change blindness paradigm.
doi:10.3389/fnhum.2017.00076 pmid:28270759 pmcid:PMC5319305 fatcat:t5xjld62mzgczbxww6ibxdc4g4

Covert orienting of visuospatial attention in the early stages of aging

Laura Lorenzo-L??pez, Sonia Doallo, Carmen Vizoso, Elena Amenedo, Socorro Rodr??guez Holgu??n, Fernando Cadaveira
2002 NeuroReport  
Electrophysiological and behavioral responses were recorded in healthy young (19^23 years) and older (56^66 years) subjects during the execution of a visuospatial attention task. The objective was to test whether covert orienting of visuospatial attention (COVAT) is sensitive to the early stages of aging. All subjects responded faster to targets following valid than invalid cues.The amplitude of the P1component of visual event-related potentials (ERP) was larger to targets following central
more » ... d cues at all SOAs. Subtle age-related changes were observed in P1 amplitude under peripheral cueing. Furthermore, older subjects presented longer reaction times (RTs) and lower P1 amplitudes regardless of the attention condition. NeuroReport 13:1^5 c 2002 Lippincott Williams & Wilkins.
doi:10.1097/00001756-200208070-00022 pmid:12167773 fatcat:mqw77f4enrh5dljmp3q2ixh76q

Neural correlates of age-related visual search decline: A combined ERP and sLORETA study

Laura Lorenzo-López, Elena Amenedo, Roberto D. Pascual-Marqui, Fernando Cadaveira
2008 NeuroImage  
Differences in the neural systems underlying visual search processes for young (n = 17, mean age 19.6± 1.9) and older (n= 22, mean age 68.5 ± 6) subjects were investigated combining the Event-Related Potential (ERP) technique with standardized Low-Resolution brain Electromagnetic Tomography (sLORETA) analyses. Behavioral results showed an increase in mean reaction times (RTs) and a reduction in hit rates with age. The ERPs were significantly different between young and older subjects at the P3
more » ... omponent, showing longer latencies and lower amplitudes in older subjects. These ERP results suggest an age-related decline in the intensity and speed of visual processing during visual search that imply a reduction in attentional resources with normal aging. The sLORETA data revealed a significantly reduced neural differentiation in older subjects, who recruited bilateral prefrontal regions in a nonselective manner for the different search arrays. Finally, sLORETA betweengroup comparisons revealed that relative to young subjects, older subjects showed significantly reduced activity in anterior cingulate cortex as well as in numerous limbic and occipitotemporal regions contributing to visual search processes. These findings provide evidence that the neural circuit supporting this cognitive process is vulnerable to normal aging. All these attentional factors could contribute to poorer performance of older compared to young subjects in visual search tasks.
doi:10.1016/j.neuroimage.2008.02.041 pmid:18395470 fatcat:oehzr2icjbhnrb4r552o4hje5m

Effects of stimulus location on automatic detection of changes in motion direction in the human brain

Paula Pazo-Álvarez, Elena Amenedo, Laura Lorenzo-López, Fernando Cadaveira
2004 Neuroscience Letters  
We extended the results of a previous report by further exploring the underlying mechanisms of an electrophysiological index of attentionfree memory-based detection mechanism to motion-direction changes in the human visual system. By means of presenting bilateral, rightand left-hemifield stimulation in separate conditions, we tried to assess whether the location of the stimuli within the peripheral visual field affected the processing of motion-direction deviations, and to identify brain
more » ... involved in the detection of unattended infrequent changes of motion direction using low-resolution brain electromagnetic tomography (LORETA). Results indicated that the ERP component related to visual change was not affected by stimulus location, and that bilateral temporal and medial regions were activated during this deviance-related response regardless of the hemifield stimulated. The bilateral activation foci observed in this study suggest that brain generators of this deviance-related component could be located at the vicinity of motion processing areas.
doi:10.1016/j.neulet.2004.08.073 pmid:15519739 fatcat:h72ut5ox3jfovaieecufxsoi6a

Oscillatory Brain Activity in the Time Frequency Domain Associated to Change Blindness and Change Detection Awareness

Álvaro Darriba, Paula Pazo-Álvarez, Almudena Capilla, Elena Amenedo
2012 Journal of Cognitive Neuroscience  
■ Despite the importance of change detection (CD) for visual perception and for performance in our environment, observers often miss changes that should be easily noticed. In the present study, we employed time-frequency analysis to investigate the neural activity associated with CD and change blindness (CB). Observers were presented with two successive visual displays and had to look for a change in orientation in any one of four sinusoid gratings between both displays. Theta power increased
more » ... dely over the scalp after the second display when a change was consciously detected. Relative to no-change and CD, CB was associated with a pronounced theta power enhancement at parietal-occipital and occipital sites and broadly distributed alpha power suppression during the processing of the prechange display. Finally, power suppressions in the beta band following the second display show that, even when a change is not consciously detected, it might be represented to a certain degree. These results show the potential of time-frequency analysis to deepen our knowledge of the temporal curse of the neural events underlying CD. The results further reveal that the process resulting in CB begins even before the occurrence of the change itself. ■
doi:10.1162/jocn_a_00073 pmid:21671737 fatcat:6yz5vxaa4zdufcxrwnzwckf4yu

Preserved Suppression of Salient Irrelevant Stimuli During Visual Search in Age-Associated Memory Impairment

Laura Lorenzo-López, Ana Maseda, Ana Buján, Carmen de Labra, Elena Amenedo, José C. Millán-Calenti
2016 Frontiers in Psychology  
., 2008 Amenedo et al., 2012; Li et al., 2013; Störmer et al., 2013) , indicating a decline in the correlates of allocation of attentional resources to a lateralized target stimulus.  ...  Previous studies have reported age-related deficits in motor-response production in visual search (Amenedo et al., 2012; Wiegand et al., 2013) and Simon (Van der Lubbe and Verleger, 2002; Cespón et  ... 
doi:10.3389/fpsyg.2015.02033 pmid:26793148 pmcid:PMC4709474 fatcat:thihhwnd7zg37ax5kyqftfwzfm

Response processing during visual search in normal aging: The need for more time to prevent cross talk between spatial attention and manual response selection

Elena Amenedo, Laura Lorenzo-López, Paula Pazo-Álvarez
2012 Biological Psychology  
It is still not well known whether the age-related behavioural slowing observed during visual search is due to changes in the allocation of attention, in response activation patterns, or to a combination of both. To help in clarifying it, attention-related (N2 posterior contralateral; N2pc, and N2 central contralateral; N2cc) and response-related (Motor Potential; MP, and Reafferent Potential; RAP) event-related potentials (ERPs) were obtained in healthy young and older participants executing a
more » ... visual search task. Age was associated with N2pc and N2cc longer latencies, earlier MP onsets and longer MP rise times. Lower N2pc, higher MP and lower RAP amplitudes were also observed. Results suggest that older participants need more time to allocate spatial attention onto the target (N2pc) and to prevent cross talk between response selection and attention direction (N2cc), and that they are slower and need higher cortical activation when preparing and executing correctly selected responses (MP).
doi:10.1016/j.biopsycho.2012.06.004 pmid:22743592 fatcat:f7zkh5vva5h4jadx5443yayt64

Vertical asymmetries and inhibition of return: Effects of spatial and non-spatial cueing on behavior and visual ERPs

Francisco-Javier Gutiérrez-Domínguez, Paula Pazo-Álvarez, Sonia Doallo, Luis J. Fuentes, Laura Lorenzo-López, Elena Amenedo
2014 International Journal of Psychophysiology  
., 2004) or movement direction changes (Amenedo et al., 2007) .  ... 
doi:10.1016/j.ijpsycho.2013.12.004 pmid:24342058 fatcat:rapt27fwjbacjmxtbe3yqaasny

Fluorescence in situ hybridization analysis of the ALK gene in 2,045 non-small cell lung cancer patients from North-Western Spain (Galicia)

María Sánchez-Ares, José M. Cameselle-Teijeiro, Sergio Vázquez-Estévez, Martín Lázaro-Quintela, Ángel Vázquez-Boquete, Francisco J. Afonso-Afonso, Joaquín Casal-Rubio, Ana L. González-Piñeiro, Yolanda Rico-Rodríguez, José L. Fírvida-Pérez, Juan Ruíz-Bañobre, Elena Couso (+7 others)
2016 Oncology Letters  
Identification of anaplastic lymphoma receptor tyrosine kinase (ALK) gene rearrangements is a standard diagnostic test in patients with advanced non-small cell lung cancer (NSCLC). The current study describes the experience of ALK rearrangement detection of a referral center in the public health care system of Galicia in North-Western Spain. The fluorescence in situ hybridization (FISH) patterns of the ALK gene and the clinical and pathological features of these patients are reported. This
more » ... is also of interest for comparative purposes due to the relative geographical isolation of the area, which could have contributed to particular genetic features. A total of 2,045 tissue samples from NSCLC patients were collected between October 2010 and July 2015 and tested for ALK rearrangements by FISH. Examination of 1,686 paraffin-embedded tissue specimens and 395 cytological samples (306 cell block preparations and 53 cytological smears) was conducted, and any associations between the FISH results and clinicopathological features were assessed. The rate of successful evaluation was marginally higher in tissue samples than in cytological samples (92.9% vs. 84.1%); this difference was not significant. ALK rearrangements were identified in 82 patients(4%): 65 (79.3%) in tissue specimens, 15 (18.3%) in cell block samples and 2 (2.4%) in cytological smears. This genetic translocation appeared to be associated with a non-smoking history, younger age, female gender, stage IV and adenocarcinoma histological type. The findings demonstrate that ALK evaluation by FISH is feasible in tissue and cytological samples. The clinical and pathological features of the ALK-positive series of patients are similar to those previously reported in the literature.
doi:10.3892/ol.2016.4788 pmid:27446444 pmcid:PMC4950728 fatcat:pzhygmmv3fgejhp44x3mou4gvu

P2-167: Induction docetaxel and cisplatin followed of bi-weekly docetaxel with concurrent thoracic radiotherapy for stage III non-small cell lung cancer (NSCLC). A phase II study conducted by the Galician Lung Cancer Group (GLCG)

Joaquin R. Casal, Sergio E. Vazquez, Martin Q. Lázaro, Urbano Anido, Jose L. Firvida, Elena Alvarez, Gerardo Huidobro, Isaura Fernandez, Margarita Amenedo, Manolo Caeiro
2007 Journal of Thoracic Oncology  
The most satisfactory treatment for patients with locally advanced NSCLC is combination chemotherapy-radiotherapy (CT-RT). The optimal treatment modalities remain to be determined. Methods: 60 patients (pts) with inoperable locally advanced NSCLC, stage IIIAN2/IIIB (no pleural T4), were included in a phase II study with induction chemotherapy consisting of three cycles of Docetaxel 75 mg/m 2 on D1 and Cisplatin 40 mg/m 2 D1-2 every 3 weeks and, if no surgery, then received concurrent CT-RT with
more » ... Docetaxel 30 mg/m 2 every 2 weeks for four courses, during thoracic conformal radiotherapy (60-66 Gys, 180 cGy/day). The primary objective: overall survival; secondary: progression free survival, response rate (RR) and toxicity. Median follow-up: 9.1 mo. Results: The pts characteristics were: mean age 62.9 yrs (43-74); male/ female: 56/4; ECOG 0/1 in 17/43 pts; stage IIIAN2: 17 pts (28.3%) and stage IIIB 43 pts (71.7%). 56 pts were evaluables for response and 58 pts for toxicity. Induction chemotherapy response: 1 CR and 34 PR (RR 62.5%; CI95%:50-75), 16 SD (28.6%) and 5 PD (8.9%). 6 pts went to surgery: 3 pPR, 1 pSD, 1 pPD and 1 unresectable. 34 pts completed concurrent CT-RT treatment with 6 CR, 21 PR, 4 SD and 3 PD (RR 79.3%; CI95%:66-93). The median time to progression was 13 mo and median overall survival was 14 mo. The progression-free survival and overall survival at 1 year was 52% and 62% respectively. A total of 163 cycles of induction chemotherapy were administered (2.8 per pts), with the main toxicity (NCI-CTC) per pts Grade (g) 1-2/3-4 (%) was as follows: neutropenia 20.6/24.1; anemia 44.8/1.7; nausea/vomiting 39.6/1.7; fatigue 34.5/1.7; diarrhea 22.4/0; allergy 5.2/1.7; one toxic death were scored. The main toxicities (RTOG) in concurrent CT-RT were: g1-2 neutropenia/anemia 30.7/38.4 5% of pts; g1-2/3 esophagitis in 51.2/2.5% and g1-2/3 pneumonitis in 20.5/2.5 % of pts. Conclusions: Docetaxel and Cisplatin induction chemotherapy followed by bi-weekly docetaxel with concurrent thoracic radiotherapy is a feasible treatment option, showing good clinical activity and tolerability for locally advanced NSCLC.
doi:10.1097/01.jto.0000283825.39615.3b fatcat:jdjggzwhzzefxcsw5ifabbuf3m

Page 509 of Journal of Clinical Oncology Vol. 26, Issue SUPPLEMENT [page]

2008 Journal of Clinical Oncology  
Ambros, Peter F. 10009 Ambrosini, Gianni 19099 Ambrosone, Christine B. 5540 Ambulkar, Indu B. 17039 Ambulkar, Indumati 11571 Amdur, Richard L7o5S Amenedo, Margarita 7561, 18501, 19097 Ames, Matthew M.  ...  Allen, Brittany 19084 15042 22077 7552, 19020 4623 20523 7047 20550 16069, 16112 len-Auerbach, Martin Sebastian 10528 lende, Daniela 22079 len-Freda, Erin 2033, 2557 lerton, Jeffrey P. 14565 lia, Elena  ... 

Page 4177 of Psychological Abstracts Vol. 88, Issue 10 [page]

2001 Psychological Abstracts  
Altbicker, Vilmos, 29418 Altenmiiller, Eckart O., 29579 Alvarez, Alvin N., 31125 Alvarez, Nelson, 31294 Alvarez, Xoan A., 31278 Alvesson, Mats, 32099 Amado, Alfred J., 29008 Amdur, Richard L., 29058 Amenedo  ...  ., 29057 Achille, Marie, 31447 Ackerman, Grant, 32011 Acquarini, Elena, 29067 Acquas, E., 29530 Adams, Catherine, 30872, 31522 Adams, Derek G., 31971 Adams, Robert A., 30959 Ademoglu, Ahmet, 29590 Aditya  ... 

Page 4645 of Psychological Abstracts Vol. 86, Issue 11 [page]

1999 Psychological Abstracts  
., 34629 Amenedo, Elena, 33278 Améry, Jean, 34314 Amess, P.  ...  A., 33311 Ardila, Alfredo, 32684, 34666 Ardovini, Cristiano, 34493 Arehart, Kathryn Hoberg, 34697 Arendt, Josephine, 33312, 34705 Arevalo, C., 33321 Arguelles, Maria Elena, 35465 Arias, Ileana, 34321 Arikan  ... 
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