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1.
Psychol Res ; 85(2): 887-898, 2021 Mar.
Article in English | MEDLINE | ID: mdl-31836933

ABSTRACT

Shifting attention between visual and auditory targets is associated with reaction time costs, known as the modality-shifting effect. The type of modality shifted from, e.g., auditory or visual is suggested to have an effect on the degree of cost. Studies report greater costs shifting from visual stimuli, yet notably used visual stimuli that are also identified slower than the auditory. It is not clear whether the cost is specific to modality effects, or with identification speed independent of modality. Here, to interpret whether the effects are due to modality or identification time, switch costs are instead compared with auditory stimuli that are identified slower than the visual (inverse of tested previously). A second condition used the same auditory stimuli at a low intensity, allowing comparison of semantically identical stimuli that are even slower to process. The current findings contradicted suggestions of a general difficulty in shifting from visual stimuli (as previously reported), and instead suggest that cost is reduced when targets are preceded by a more rapidly processed stimulus. 'Modality-Shifting' as it is often termed induces shifting costs, but the costs are not because of a change of modality per se, but because of a change in identification speed, where the degree of cost is dependent on the processing time of the surrounding stimuli.


Subject(s)
Attention/physiology , Cognition/physiology , Time Perception/physiology , Visual Perception/physiology , Adult , Auditory Perception , Female , Humans , Male , Photic Stimulation , Reaction Time , Semantics
2.
J Cogn Neurosci ; 32(5): 906-916, 2020 05.
Article in English | MEDLINE | ID: mdl-31905092

ABSTRACT

Our visual inputs are often entangled with affective meanings in natural vision, implying the existence of extensive interaction between visual and emotional processing. However, little is known about the neural mechanism underlying such interaction. This exploratory transcranial magnetic stimulation (TMS) study examined the possible involvement of the early visual cortex (EVC, Area V1/V2/V3) in perceiving facial expressions of different emotional valences. Across three experiments, single-pulse TMS was delivered at different time windows (50-150 msec) after a brief 10-msec onset of face images, and participants reported the visibility and perceived emotional valence of faces. Interestingly, earlier TMS at ∼90 msec only reduced the face visibility irrespective of displayed expressions, but later TMS at ∼120 msec selectively disrupted the recognition of negative facial expressions, indicating the involvement of EVC in the processing of negative expressions at a later time window, possibly beyond the initial processing of fed-forward facial structure information. The observed TMS effect was further modulated by individuals' anxiety level. TMS at ∼110-120 msec disrupted the recognition of anger significantly more for those scoring relatively low in trait anxiety than the high scorers, suggesting that cognitive bias influences the processing of facial expressions in EVC. Taken together, it seems that EVC is involved in structural encoding of (at least) negative facial emotional valence, such as fear and anger, possibly under modulation from higher cortical areas.


Subject(s)
Emotions/physiology , Facial Expression , Facial Recognition/physiology , Transcranial Magnetic Stimulation , Visual Cortex/physiology , Adult , Brain Mapping , Female , Humans , Male , Young Adult
3.
Br J Psychol ; 110(3): 519-529, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30291634

ABSTRACT

It has been demonstrated that the use of social networking sites late at night can lead to sleep-related problems that extend into the next day. A common explanation is that the light emitted from screens is disrupting the users' circadian rhythms. An alternative explanation is that the social cognition inherent in the use of social networking sites is responsible. Here, the two factors were looked at together. Participants used Facebook on iPad tablets before sleep. This was done on different nights with two lighting conditions and with two levels of content. In the 'light' condition, blue wavelength light was manipulated so that it was either full wavelength or blue light filtered. In the 'alertness' condition, the personal significance of the content was changed from personally relevant to irrelevant. A modified version of the Pittsburgh Sleep Quality Index was used to measure sleep-related problems. No evidence was found that simply filtering blue light or simply removing relevant content improved sleep quality. However, the two factors interacted. The results suggest that the light emitted from screens can affect sleep quality under some conditions but this is behaviourally irrelevant in the context of normal Facebook usage.


Subject(s)
Attention/physiology , Light/adverse effects , Sleep Wake Disorders/etiology , Social Media/statistics & numerical data , Adolescent , Analysis of Variance , Circadian Rhythm/physiology , Female , Humans , Lighting , Male , Young Adult
4.
Q J Exp Psychol (Hove) ; 71(8): 1663-1671, 2018 Aug.
Article in English | MEDLINE | ID: mdl-28649944

ABSTRACT

Careful systematic tests of hearing ability may miss the cognitive consequences of sub-optimal hearing when listening in the real world. In Experiment 1, sub-optimal hearing is simulated by presenting an audiobook at a quiet but discriminable level over 50 min. Recall of facts, words and inferences are assessed and performance compared to another group at a comfortable listening volume. At the quiet intensity, participants are able to detect, discriminate and identify spoken words but do so at a cost to sequential accuracy and fact recall when attention must be sustained over time. To exclude other interpretations, the effects are studied in Experiment 2 by comparing recall to the same sentences presented in isolation. Here, the differences disappear. The results demonstrate that the cognitive consequences of listening at low volume arise when sustained attention is demanded over time.


Subject(s)
Attention/physiology , Auditory Perception/physiology , Hearing/physiology , Speech Perception/physiology , Acoustic Stimulation , Adolescent , Adult , Female , Humans , Male , Mental Recall/physiology , Middle Aged , Psychoacoustics , Self Concept , Vocabulary , Young Adult
5.
Perception ; 44(12): 1371-82, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26562860

ABSTRACT

Why attention lapses during prolonged tasks is debated, specifically whether errors are a consequence of under-arousal or exerted effort. To explore this, we investigated whether increased impulsivity is associated with effortful processing by modifying the demand of a task by presenting it at a quiet intensity. Here, we consider whether attending at low but detectable levels affects impulsivity in a population with intact hearing. A modification of the Sustained Attention to Response Task was used with auditory stimuli at two levels: the participants' personal "lowest detectable" level and a "normal speaking" level. At the quiet intensity, we found that more impulsive responses were made compared with listening at a normal speaking level. These errors were not due to a failure in discrimination. The findings suggest an increase in processing time for auditory stimuli at low levels that exceeds the time needed to interrupt a planned habitual motor response. This leads to a more impulsive and erroneous response style. These findings have important implications for understanding the nature of impulsivity in relation to effortful processing. They may explain why a high proportion of individuals with hearing loss are also diagnosed with Attention Deficit Hyperactivity Disorder.


Subject(s)
Attention , Impulsive Behavior , Loudness Perception , Reaction Time , Speech Perception , Acoustic Stimulation , Adolescent , Adult , Arousal , Auditory Threshold , Female , Humans , Inhibition, Psychological , Male , Middle Aged , Psychomotor Performance , Young Adult
6.
Rev bras queimaduras ; 14(1): 31-34, 2015.
Article in Portuguese | LILACS | ID: biblio-1392967

ABSTRACT

Sabemos que o Atendimento Pré-Hospitalar (APH) à vítima queimada ainda é uma área bastante carente de informações precisas no Brasil. Os socorristas, muitas vezes, têm pouco conhecimento para fazer um atendimento rápido, eficiente e eficaz ou possuem material escasso - e às vezes inexistentes - em suas viaturas ou bases de atendimento. Além disso, o estresse que este tipo de evento causa faz com que as equipes de socorro nem sempre se sintam confortáveis e seguras em assumir um evento tão devastador, principalmente se os envolvidos forem crianças, idosos ou múltiplas vítimas. A publicação de Patrick Bourke, na revista Ambulance UK (Reino Unido), aponta a importância do resfriamento correto da queimadura no cenário pré-hospitalar, mostrando a história desta prática, o motivo e o modo correto de como este procedimento tão simples e importante pode ser realizado. O correto resfriamento da lesão, a proteção de infecções secundárias, a prevenção da hipotermia clínica e o alívio da dor ainda no APH irão influenciar diretamente na evolução destes pacientes, reduzindo custos com medicação, tempo de internação e prognóstico desta vítima.


It is known that Prehospital Emergency Care (PHEC) to burned victims is an area needing accurate information in Brazil. Quite often, PHEC responders have little knowledge to provide fast, efficient and effective care or count on little - sometimes, inexistent - material in their ambulances or care units. Besides, the stress caused by this kind of event makes rescue teams not always comfortable and confident to respond to a such devastating event, especially when children, elderly or multiple victims are involved. Patrick Bourke's article published in Ambulance UK (United Kingdom) points out the importance of burn fast cooling in prehospital care, showing the history of this practice, the reason for performing it and the correct way this simple and important procedure can be carried out. The injury correct cooling, protection against secondary infections, clinical and pain relief during PHEC will directly influence the patient's outcome, reducing medication costs and hospital stay and improving victim's prognosis.


Subject(s)
Humans , Bandages/standards , Burns/therapy , Pain Clinics , Emergency Medical Services/methods , Hypothermia, Induced/standards
7.
PLoS One ; 9(6): e98268, 2014.
Article in English | MEDLINE | ID: mdl-24932494

ABSTRACT

Contour integration is a fundamental visual process. The constraints on integrating discrete contour elements and the associated neural mechanisms have typically been investigated using static contour paths. However, in our dynamic natural environment objects and scenes vary over space and time. With the aim of investigating the parameters affecting spatiotemporal contour path integration, we measured human contrast detection performance of a briefly presented foveal target embedded in dynamic collinear stimulus sequences (comprising five short 'predictor' bars appearing consecutively towards the fovea, followed by the 'target' bar) in four experiments. The data showed that participants' target detection performance was relatively unchanged when individual contour elements were separated by up to 2° spatial gap or 200 ms temporal gap. Randomising the luminance contrast or colour of the predictors, on the other hand, had similar detrimental effect on grouping dynamic contour path and subsequent target detection performance. Randomising the orientation of the predictors reduced target detection performance greater than introducing misalignment relative to the contour path. The results suggest that the visual system integrates dynamic path elements to bias target detection even when the continuity of path is disrupted in terms of spatial (2°), temporal (200 ms), colour (over 10 colours) and luminance (-25% to 25%) information. We discuss how the findings can be largely reconciled within the functioning of V1 horizontal connections.


Subject(s)
Form Perception/physiology , Orientation/physiology , Photic Stimulation/methods , Adolescent , Adult , Color Perception , Female , Fovea Centralis/physiology , Humans , Male , Young Adult
8.
Brain Res ; 1530: 32-43, 2013 Sep 12.
Article in English | MEDLINE | ID: mdl-23892109

ABSTRACT

Looking for an object that may be present in a cluttered visual display requires an advanced specification of that object to be created and then matched against the incoming visual input. Here, fast event-related fMRI was used to identify the brain networks that are active when preparing to search for a visual target. By isolating the preparation phase of the task it has been possible to show that for an identical stimulus, different patterns of cortical activation occur depending on whether participants anticipate a 'feature' or a 'conjunction' search task. When anticipating a conjunction search task, there was more robust activation in ventral occipital areas, new activity in the transverse occipital sulci and right posterior intraparietal sulcus. In addition, preparing for either type of search activated ventral striatum and lateral cerebellum. These results suggest that when participants anticipate a demanding search task, they develop a different advanced representation of a visually identical target stimulus compared to when they anticipate a nondemanding search.


Subject(s)
Attention/physiology , Brain/physiology , Psychomotor Performance/physiology , Adolescent , Adult , Brain Mapping/methods , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Photic Stimulation/methods , Task Performance and Analysis , Young Adult
9.
J Burn Care Res ; 34(6): 639-43, 2013.
Article in English | MEDLINE | ID: mdl-23412329

ABSTRACT

Our burn center previously reported a significant incidence of scald burns from tap water among patients treated at the center. However, mechanism of these scalds was not investigated in detail. A recent series of pediatric patients who sustained scalds while bathing in the sink was noted. To evaluate the extent of these injuries and create an effective prevention program for this population, a retrospective study of bathing-related sink burns among pediatric patients was performed. Patients between the ages of 0 and 5.0 years who sustained scald burns while being bathed in the sink were included in this study. Sex, race, age, burn size, length of stay, and surgical procedures were reviewed. During the study period of January 2003 through August 2008, 56 patients who were scalded in the sink were admitted, accounting for 54% of all bathing-related scalds. Among these, 56% were boys and 45% were Hispanic. Mean age was 0.8 ± 0.1 years. Burn size and hospital length of stay averaged 5 ± 0.7% and 11 ± 1 days, respectively. Of this group, 10.7% required skin grafting. The overwhelming majority (94% of patients) were discharged home. The remaining patients were discharged to inpatient rehabilitation, foster care, and others. Pediatric scald burns sustained while bathing in a sink continue to be prevalent at our burn center. Because of limited space and the child's proximity to faucet handles and water flow, sinks are an unsafe location to bathe a child. While such practice may be necessary for some families, comprehensive burn prevention education must address this hazard.


Subject(s)
Accidents, Home/statistics & numerical data , Baths/adverse effects , Burns/etiology , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , Length of Stay/statistics & numerical data , Male , Prevalence , Registries , Retrospective Studies , Risk Factors , Skin Transplantation , United States/epidemiology , Water
10.
Percept Psychophys ; 70(7): 1383-92, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18927021

ABSTRACT

Voluntary reorienting of attention in real depth situations is characterized by an attentional bias to locations nearer the viewer once attention is deployed to a spatially cued object in depth. Previously, this effect (initially referred to as the near effect) was attributed to access of a 3-D viewer-centered spatial representation for guiding attention in 3-D space. The aim of this study was to investigate whether the near effect could have been associated with the position of the response hand, which was always near the viewer in previous studies that investigated endogenous attentional shifts in real depth. In Experiment 1, the response hand was placed at either the near or far target depth in a depth-cuing task. Placing the response hand at the far target depth abolished the near effect, but failed to bias spatial attention to the far location. Experiment 2 showed that the response hand effect was not modulated by the presence of an additional (passive) hand, whereas Experiment 3 confirmed that attentional prioritization of the passive hand was not masked by the influence of the responding hand on spatial attention in Experiment 2. The pattern of results is most consistent with the idea that response preparation can modulate spatial attention within a 3-D viewer-centered spatial representation.


Subject(s)
Attention , Hand , Posture , Visual Perception , Humans , Young Adult
11.
J Med Entomol ; 45(2): 222-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18402137

ABSTRACT

Ongoing work in oak woods in Killarney National Park in southwestern Ireland is focusing on the factors influencing the fine-scale aggregated distribution of Ixodes ricinus L. (Acari: Ixodidae) on the ground. The extent of reuse of stems of vegetation as questing points by adult ticks was determined by paint-marking stems on which ticks were found, counting and removing these ticks, and subsequently reexamining the same stems for ticks on two further occasions. Overall, an estimated 2,967 stems in 123 separate rush plants (Juncus effusus L.) were examined. Statistical analysis of the data demonstrated a highly significant reoccupancy by ticks of stems previously and recently used. Furthermore, it is shown that the extent of stem reuse by ticks is significantly and positively correlated with the numbers of ticks originally observed on those stems. Although other factors may be involved in generating clumping of ticks, the results are compatible with the proposition that aggregation of I. ricinus on the ground is pheromone-mediated. The findings are discussed in relation to what is known about the powers of lateral movement of I. ricinus on the ground and the possible implications for the performance of tick traps.


Subject(s)
Appetitive Behavior/physiology , Ixodes/physiology , Animals , Female , Magnoliopsida , Male , Plant Stems
12.
Psychol Sci ; 16(3): 208-13, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15733201

ABSTRACT

Even dissimilar tasks interfere with one another when done together. We used visual search to examine the underlying cause of such interference. In many models, visual search is a process of biased competition controlled by a template describing the target to be sought. When the display is processed, matching against this template guides attention to the target. We show that increasing template complexity increased interference with a dissimilar concurrent task, story memory. This result was independent of reaction time: Increases in template complexity were associated with no increase in search time in Experiment 1 and with a decrease in search time in Experiment 2. The results show that the dual-task demands of visual search reflect the complexity of the template used in task control, and that this factor can be isolated from other sources of difficulty.


Subject(s)
Attention , Discrimination Learning , Memory, Short-Term , Pattern Recognition, Visual , Problem Solving , Verbal Learning , Adolescent , Adult , Decision Making , Female , Humans , Male , Psychophysics , Reaction Time , Speech Perception
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