Consulta: subjectFacets:"Expectancy"
Registros recuperados: 6
Data/hora: 04/06/2024 02:43:10

A neutral cue facilitates detection of a visual target by modulating attention
Provedor de dados: 48
Autores: HAMAME,CARLOS M; DELANO,PAÚL H; ROBLES,LUIS.
Twelve rats were trained to perform a two-choice visual detection task in which a right or left light was presented and the animáis were required to press the lever located under the illuminated light for a food reward. In seventy percent of the triáis the target light was preceded by presentation of a neutral cue (a central light). Relevance of the neutral cue for detection of the target was analyzed by comparing behavioral Índices of attention in its presence and absence. Accuracy was significantly higher in presence than in absence of the neutral cue, while mean response latencies were lower in presence than in absence of the neutral cue. These results indicate that the animáis allocated attentional resources on the target detection during a high...
Tipo: Journal article
Palavras-chave: Alerting effect; Attention; Detection task; Expectancy; Neutral cue; Rat.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602008000400012

Relevance of a neutral cue in a two-choice detection task in the rat
Provedor de dados: 48
Autores: HAMAME,CARLOS M; DELANO,PAUL H; ROBLES,LUIS.
Relevance of a neutral cue for performance in a two-choice visuospatial detection task was examined. Nine rats were trained, 5 with short intertrial interval (ITI) and 4 with long ITI, to detect a target (lateral lights) presented after a neutral-cue (central light). The removal of the neutral-cue decreased accuracy and increased response latencies and omissions. These results demonstrate that a neutral-cue, preceding the target, is relevant for the performance, suggesting that rats are highly expectant during the neutral-cue and reallocate attentional resources during ITI. Furthermore, latencies were higher, omissions were lower and the fall of accuracy was greater for rats with long than with short ITI, which could indicate that the neutral-cue was more...
Tipo: Journal article
Palavras-chave: Attention; Expectancy; Neutral cue; Attentional task; Rat.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000200008

Relative contribution of expectancy and immediate arousal to the facilitatory effect of an auditory accessory stimulus
Provedor de dados: 56
Autores: Del-Fava,F.; Ribeiro-do-Valle,L.E.
An auditory stimulus speeds up a digital response to a subsequent visual stimulus. This facilitatory effect has been related to the expectancy and the immediate arousal that would be caused by the accessory stimulus. The present study examined the relative contribution of these two influences. In a first and a third experiment a simple reaction time task was used. In a second and fourth experiment a go/no-go reaction time task was used. In each of these experiments, the accessory stimulus preceded the target stimulus by 200 ms for one group of male and female volunteers (G Fix). For another group of similar volunteers (G Var) the accessory stimulus preceded the target stimulus by 200 ms in 25% of the trials, by 1000 ms in 25% of the trials and was not...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Priming; Arousal; Alertness; Expectancy; Attention.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000800006

Facilitatory effects of an auditory warning stimulus in a visual location identification task and a visual shape identification task
Provedor de dados: 56
Autores: Bueno,V.F.; Ribeiro-do-Valle,L.E.
The occurrence of a weak auditory warning stimulus increases the speed of the response to a subsequent visual target stimulus that must be identified. This facilitatory effect has been attributed to the temporal expectancy automatically induced by the warning stimulus. It has not been determined whether this results from a modulation of the stimulus identification process, the response selection process or both. The present study examined these possibilities. A group of 12 young adults performed a reaction time location identification task and another group of 12 young adults performed a reaction time shape identification task. A visual target stimulus was presented 1850 to 2350 ms plus a fixed interval (50, 100, 200, 400, 800, or 1600 ms, depending on the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Expectancy; Time course; Priming; Auditory temporal processing; Visual form processing; Reaction time.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2012001100007

Experimental context modulates warning signal effects
Provedor de dados: 56
Autores: Machado-Pinheiro,W.; Faria Jr.,A.J.P.; Gawryszewski,L.G.; Ribeiro-do-Valle,L.E.
Previous studies have shown that saccadic eye responses but not manual responses were sensitive to the kind of warning signal used, with visual onsets producing longer saccadic latencies compared to visual offsets. The aim of the present study was to determine the effects of distinct warning signals on manual latencies and to test the premise that the onset interference, in fact, does not occur for manual responses. A second objective was to determine if the magnitude of the warning effects could be modulated by contextual procedures. Three experimental conditions based on the kind of warning signal used (visual onset, visual offset and auditory warning) were run in two different contexts (blocked and non-blocked). Eighteen participants were asked to...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Reaction times; Attention; Distractor; Preparation; Expectancy.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000700016

Looking for the GAP effect in manual responses and the role of contextual influences in reaction time experiments
Provedor de dados: 56
Autores: Faria Jr.,A.J.P.; Machado-Pinheiro,W.
When the offset of a visual stimulus (GAP condition) precedes the onset of a target, saccadic reaction times are reduced in relation to the condition with no offset (overlap condition) - the GAP effect. However, the existence of the GAP effect for manual responses is still controversial. In two experiments using both simple (Experiment 1, N = 18) and choice key-press procedures (Experiment 2, N = 12), we looked for the GAP effect in manual responses and investigated possible contextual influences on it. Participants were asked to respond to the imperative stimulus that would occur under different experimental contexts, created by varying the array of warning-stimulus intervals (0, 300 and 1000 ms) and conditions (GAP and overlap): i) intervals and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Reaction times; Attention; Preparation; Expectancy; Contextual influences.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000800007