The dot-probe task is a common task to assess attentional bias toward different stimuli and how groups differ (e.g., attentional bias in anxiety disorders). However, measuring reaction time has been suggested to be unreliable. Neuroimaging methods such as fMRI were shown to be more reliable in assessing attentional bias, but fMRI has poor temporal resolution and therefore cannot assess timing of attention. ERPs have been used to examine the time course of attentional bias. Although ERP research may be more reliable than reaction time, there have been inconsistencies in the literature. This review systematically searched for articles that used the dot-probe task with facial expressions and measured neural correlates with ERP. We found that some of the inconsistencies might be the cause of methodological differences (e.g., timing of stimuli), differences in emotional expression, and/or sample differences (e.g., sex, age, etc.). Suggestions on how future research could address the issues presented in this review were discussed.

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The effect of cannabis on emotional processing was investigated using event-related potential paradigms (ERPs). ERPs associated with emotional processing of cannabis users, and non-using controls, were recorded and compared during an implicit and explicit emotional expression recognition and empathy task. Comparisons in P3 component mean amplitudes were made between cannabis users and controls. Results showed a significant decrease in the P3 amplitude in cannabis users compared to controls. Specifically, cannabis users showed reduced P3 amplitudes for implicit compared to explicit processing over centro-parietal sites which reversed, and was enhanced, at fronto-central sites. Cannabis users also showed a decreased P3 to happy faces, with an increase to angry faces, compared to controls. These effects appear to increase with those participants that self-reported the highest levels of cannabis consumption. Those cannabis users with the greatest consumption rates showed the largest P3 deficits for explicit processing and negative emotions. These data suggest that there is a complex relationship between cannabis consumption and emotion processing that appears to be modulated by attention.

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The effects of residual cannabis use on emotional expression recognition and the P3 event-related potential in participants who scored highly for subclinical depression were investigated. Comparisons were made between participants who were classified as depressed or nondepressed cannabis users, depressed non-cannabis users and controls who neither used cannabis nor were characterized as being depressed. In an emotional expression recognition task, participants were asked to respond to faces depicting happy, angry, fearful, and neutral faces either implicitly, explicitly, or empathically. Residual cannabis use and mood was shown to modulate the P3 event related potential during the task. There was a significant reduction in the P3 amplitude between depressed and nondepressed participants. Residual cannabis use further reduced the P3 amplitude with the greatest deficits being associated with cannabis users who scored highly for subclinical depression. These effects were greatest for explicit and empathic processing of faces depicting negative emotions. We conclude from our study that cannabis and mood state interact to reduce the amplitude of the P3 which has been associated with attention to emotion.

As part of an ongoing research program into the relationship between cannabis use and emotion processing, participants were assessed on their level of cannabis exposure using the Recreational Cannabis Use Examination, a measure developed specifically to assess cannabis use in Colorado post state legalization. Three groups were created based on self-reported use: a control group who have never used, a casual user group and a chronic user group. Each participant also completed two measures of mood assessment, the Center for Epidemiologic Studies Depression Scale and the State-Trait Anxiety Inventory. Relationships between cannabis use groups and scores on these measures were then analyzed using both correlations and multivariate analysis of variance. Results indicate a relationship between casual cannabis use and scoring highly for depressive symptomatology on the Center for Epidemiologic Studies Depression Scale. There were no significant relationships between cannabis use and scores on the State-Trait Anxiety Inventory.

Research on noise shows that a variety of effects includingstress, annoyance, and performance decrements exist for certain types of sounds. Noise interferes with cognitive ability by overloading the attentional system or simply distracting from efficient encoding or rehearsal, but very little research has extended those findings to recreation or natural environments such as those found in national parks. By exposing participants to one of four soundscape conditions-eontrol, natural, natural with voices, and natural with ground traffic-the current project tested the effect of sound conditions on the recognition and recall of factual information presented whereas viewing scenes of national parks. Both the natural with voices and natural with ground traffic conditions caused significantdecreases in memory scores while the natural condition showed no differences from the control condition. Implications for sound management strategies are discussed in the context of current legislation and recent field research. Avenues for future research to clarify the mode of memory interference are discussed.

The effects of intensity on chromatic perceptive field size were investigated along the horizontal meridian at 10 degrees temporal eccentricity by manipulating stimulus intensity from 0.3 to 3.3 log trolands. Following light adaptation, observers described the hue and saturation of monochromatic stimuli (440-660 nm, in 10 nm steps) for a series of test sizes (0.098-3 degrees) presented along the time period associated with the cone plateau of the dark-adaptation function. Perceptive field sizes of the four elemental hues (red, green, yellow, and blue) and the saturation component were estimated by three observers at each intensity level for each wavelength. In general, perceptive field sizes of blue and red are the smallest, and yellow and green are the largest. Furthermore, perceptive field sizes of all four hues decrease with increasing stimulus intensity, though the absolute change is largest for green and yellow. The decrease in size with increase in intensity cannot be completely explained in terms of saturation or rod signals and is likely, then, attributable to a cone-based mechanism.