We propose that explicit vision advances in reverse hierarchical direction, as shown for perceptual learn-ing. Processing along the feedforward hierarchy of areas, leading to increasingly complex represen-tations, is automatic and implicit, while conscious perception begins at the hierarchy’s top, gradually re-turning downward as needed. Thus, our initial con-scious percept—vision at a glance—matches a highlevel, generalized, categorical scene interpretation, identifying “forest before trees.” For later vision with scrutiny, reverse hierarchy routines focus attention to specific, active, low-level units, incorporating into conscious perception detailed information available there. Reverse Hierarchy Theory dissociates between early explicit perception and implicit low-level vision,

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This meta-analysis of 172 studies (N � 2,263 anxious, N � 1,768 nonanxious) examined the boundary conditions of threat-related attentional biases in anxiety. Overall, the results show that the bias is reliably demonstrated with different experimental paradigms and under a variety of experimental conditions, but that it is only an effect size of d � 0.45. Although processes requiring conscious perception of threat contribute to the bias, a significant bias is also observed with stimuli outside awareness. The bias is of comparable magnitude across different types of anxious populations (individuals with different clinical disorders, high-anxious nonclinical individuals, anxious children and adults) and is not observed in nonanxious individuals. Empirical and clinical implications as well as future directions for research are discussed.

Identification of a 1st target stimulus in a rapid serial visual presentation sequence leads to transient impairment in report for a 2nd target;this is known as the attentional blink (AB). This AB impairment was substantially alleviated for emotionally significant target words. AB sparing was not attributable to a variety of nonaffective stimulus factors that could result in augmented distinctiveness. Arousal value, not the valence of stimulus events, was found to be responsible for AB sparing. These results suggest that arousal is associated with decreased attentional prerequisites for awareness, enabling emotional significance to shape perceptual experience. Perceptions and memories are not all created equal, nor should they be. It has been long known that memories for the significant and mundane events in a person’s life are not formed with equal durability and fidelity but are instead modulated by their emotional significance (for a review, see Christianson, 1992). A functionalist account suggests this difference in the fate of remembered and forgotten events is due to the fact that memories are to serve some predictive utility that aids one’s ability to later navigate within

Visual input is processed in parallel in the early stages of the visual system. Later, object recognition processes are also massively parallel, matching a visual object with a vast array of stored representation. A tight bottleneck in processing lies between these stages. It permits only one or a few visual objects at any one time to be submitted for recognition. That bottleneck limits performance on visual search tasks when an observer looks for one object in a field containing distracting objects. Guided Search is a model of the workings of that bottleneck. It proposes that a limited set of attributes, derived from early vision, can be used to guide the selection of visual objects. The bottleneck and recognition processes are modeled using an asynchronous version of a diffusion process. The current version (Guided Search 4.0) captures a wide range of empirical findings.

This article reports a theoretical and experimental attempt to relate and contrast 2 traditionally separate research programs: inattentional blindness and attention capture. Inattentional blindness refers to failures to notice unexpected objects and events when attention is otherwise engaged. Attention capture research has traditionally used implicit indices (e.g., response times) to investigate automatic shifts of attention. Because attention capture usually measures performance whereas inattentional blindness measures awareness, the 2 fields have existed side by side with no shared theoretical framework. Here, the authors propose a theoretical unification, adapting several important effects from the attention capture literature to the context of sustained inattentional blindness. Although some stimulus properties can influence noticing of unexpected objects, the most influential factor affecting noticing is a person’s own attentional goals. The authors conclude that many—but not all—aspects of attention capture apply to inattentional blindness but that these 2 classes of phenomena remain importantly distinct.

this article. We also thank Stephan Dekker for technical assistance

The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the probable target location. Voluntary attention enhances the perceptual representation of the stimulus in the cued location relative to other locations. Hence, voluntary attention affects performance in experiments designed around both accuracy and reaction time. Involuntary attention affects a decision as to which location should be responded to. Because involuntary attention does not change the perceptual representation, it affects performance in reaction time experiments but not accuracy experiments. The authors obtained this pattern of results in 4 different versions of the spatial cuing paradigm. It has long been recognized that one can fixate one’s eyes on one location yet attend to another location. For example, Helmholtz (1925) noted, “It is a curious fact... that the observer may be gazing steadily... yet at the same time he can concentrate his attention on any part of the dark field he likes ” (p. 455). Wilhelm

& Automatic processes are usually thought to occur indepen-dently of any cognitive resources. This traditional view has been recently challenged by showing that temporal attention to a target stimulus is a prerequisite for ‘‘automatic’ ’ response priming. The event-related potential (ERP) study reported here extends this research by pursuing a somewhat different approach. In two experiments, it was investigated whether masked semantic priming effects can be modulated by temporal attention to the prime using a cueing procedure. We hypothesized that masked priming is amplified when attention is directed to the stimulus stream in the time window of masked prime presentation, even in the absence of any prime awareness. ERPs were recorded while subjects performed a primed lexical decision task. Target words were preceded by semantically related or unrelated masked prime words, which were not consciously identified. A cue stimulus prompted subjects to direct their attention to the stimulus stream either shortly before the masked prime (short cue interval) or a long time interval before. Priming affected the amplitude of the N400 ERP component, an electrophysiological index of semantic processing. Unrelated prime–target pairs elicited a larger N400 than related pairs (N400 priming effect). Most importantly, this masked N400 priming effect was strongest when the cue inter-val and the stimulus onset asynchronies were short. The pres-ent results show that temporal attention to the prime is a prerequisite for obtaining masked N400 priming effects. They also demonstrate that unconscious automatic processes are susceptible to attentional modulation. &

Several theories of the neural correlates of consciousness assume that there is a continuum of perception, associated with a gradual change in the intensity of brain activation. But some models, considering reverberation of neural activity as necessary for conscious perception, predict a sharp non-linear transition between unconscious and conscious processing. We asked participants to evaluate the visibility of target words on a continuous scale during the attentional blink, which is known to impede explicit reports. Participants used this continuous scale in an all-or-none fashion: targets were either identified as well as targets presented outside the blink period or not detected at all. We suggest that a stochastic non-linear bifurcation in neural activity underlies the all-or-none perception observed during the attentional blink. 2