38982070
Processing of unattended emotional visual scenes.
Prime pictures of emotional scenes appeared in parafoveal vision, followed by probe pictures either congruent or incongruent in affective valence. Participants responded whether the probe was pleasant or unpleasant (or whether it portrayed people or animals). Shorter latencies for congruent than for incongruent prime-probe pairs revealed affective priming. This occurred even when visual attention was focused on a concurrent verbal task and when foveal gaze-contingent masking prevented overt attention to the primes but only if these had been preexposed and appeared in the left visual field. The preexposure and laterality patterns were different for affective priming and semantic category priming. Affective priming was independent of the nature of the task (i.e., affective or category judgment), whereas semantic priming was not. The authors conclude that affective processing occurs without overt attention--although it is dependent on resources available for covert attention--and that prior experience of the stimulus is required and right-hemisphere dominance is involved.
144085414
The Psychology of Attention
Part 1 Attention and perception: selective attention divided attention attentional set capacity and selection - theorizing about attention. Part 2 Attention, memory and action: central processing limitations in sensorimotor tasks attention and memory automaticity, effort and control.
145404795
Active Vision: The Psychology of Looking and Seeing
PASSIVE VISION AND ACTIVE VISION 1.1 Introduction 1.2 Passive vision 1.3 Visual attention 1.4 Active vision 1.5 Active vision and vision for action 1.6 Outline of the book BACKGROUND TO ACTIVE VISION 2.1 Introduction 2.2 The inhomogeneity of the visual projections 2.3 Parallel visual pathways 2.4 The oculomotor system 2.5 Saccadic eye movements 2.6 Summary VISUAL SELECTION, COVERT ATTENTION AND EYE MOVEMENTS 3.1 Covert and overt attention 3.2 Covert spatial attention 3.3 The relationship between covert and overt attention 3.4 Speed of attention 3.5 Neurophysiology of attention 3.6 Non-spatial attention 3.7 Active vision and attention 3.8 Summary VISUAL ORIENTING 4.1 Introduction 4.2 What determines the latency of orienting saccades? 4.3 Physiology of saccade initiation 4.4 What determines the landing position of orienting saccades? 4.5 Physiology of the WHERE system 4.6 The Findlay and Walker model 4.7 Development and plasticity VISUAL SAMPLING DURING TEXT READING 5.1 Introduction 5.2 Basic patterns of visual sampling during reading 5.3 Perception during fixations in reading 5.4 Language processing 5.5 Control of fixation duration 5.6 Control of landing position 5.7 Theories of eye control during reading 5.8 Practical aspects of eye control in reading 5.9 Overview VISUAL SEARCH 6.1 Visual search tasks 6.2 Theories of visual search 6.3 The need for eye movements in visual search 6.4 Eye movements in visual search 6.5 Ocular capture in visual search 6.6 Saccades in visual search: scanpaths 6.7 Physiology of visual search 6.8 Summary NATURAL SCENES AND ACTIVITIES 7.1 Introduction 7.2 Analytic studies of scene and object perception 7.3 Dynamic scenes and situations 7.4 Summary HUMAN NEUROPSYCHOLOGY 8.1 Blindsight 8.2 Neglect 8.3 Balint's syndrome and dorsal simultanagnosia 8.4 Frontal lobe damage 8.5 Orienting without eye movements 8.6 Summary SPACE CONSTANCY AND TRANS-SACCADIC INTEGRATION 9.1 The traditional approach: 'compensatory taking into account' 9.2 Trans-saccadic integration 9.3 Resolution of the conflicting results 9.4 Conclusion: The Active Vision Cycle 9.5 Future directions
196034960
THE ATTENTION SYSTEM OF THE HUMAN BRAIN
The concept of attention as central to human performance extends back to the start of experimental psychology (James 1890), yet even a few years ago, it would not have been possible to outline in even a preliminary form a functional anatomy of the human attentional system. New developments in neuroscience (Hillyard & Picton 1987, Raichle 1983, Wurtz et al 1980) have opened the study of higher cognition to physiological analysis, and have revealed a system of anatomical areas that appear to be basic to the selection of information for focal (conscious) processing. The importance of attention is its unique role in connecting the mental level of description of processes used in cognitive science with the ana­ tomical level common in neuroscience. Sperry (1988, p. 609) describes the central role that mental concepts play in understanding brain function as follows:
142966162
Anxiety: The Cognitive Perspective
Introduction. Theories of Anxiety and Cognition. Theoretical Framework. Attentional Processes. Comprehension and Memory. Worry. General Processing. Summary.
141351184
The heart's eye: Emotional influences in perception and attention.
Introduction, S. Kitayama and P.M. Niedenthal an early insight into the affect-perception interface, R.B. Zajonc the affective qualities of perception, I. Waynbaum affective regulation of perception and comprehension - amplification and semantic priming, S. Kitayama and S. Howard preferences need no inferences? - the cognitive basis of unconscious mere exposure effects, M.R. Klinger and A.G. Greenwald emotional organization of perceptual memory, P.M. Niedenthal, et al consciousness and automatic evaluation, F. Pratto comments on unconscious processing - finding emotion in the cognitive stream, M.K. Johnson and C. Weisz motivating the focus of attention, D. Derryberry and D.M. Tucker attitudes, perception, and attention, R.H. Fazio, et al automatic emotion, C.H. Hansen and R.D. Hansen attention and facial efference, C.H. Hansen and R.D. Hansen emotion and the eyewitness, H. Egeth the view from the heart's eye - a commentary, J. Bruner.
1051051
Modulation of focused attention by faces expressing emotion: evidence from flanker tasks.
Three experiments evaluated whether facial expression can modulate the allocation of focused attention. Identification of emotionally expressive target faces was typically faster when they were flanked by identical (compatible) faces compared with when they were flanked by different (incompatible) faces. This flanker compatibility effect was significantly smaller when target faces expressed negative compared with positive emotion (see Experiment 1A); however, when the faces were altered to disrupt emotional expression, yet retain feature differences, equal flanker compatibility effects were observed (see Experiment 1B). The flanker-compatibility effect was also found to be smaller for negative target faces compared compatibility with neutral target faces, and for both negative and neutral target faces compared with positive target faces (see Experiment 2). These results suggest that the constriction of attention is influenced by facial expressions of emotion.
216280
Perception without awareness: perspectives from cognitive psychology
Four basic approaches that have been used to demonstrate perception without awareness are described. Each approach reflects one of two types of experimental logic and one of two possible methods for controlling awareness. The experimental logic has been either to demonstrate a dissociation between a measure of perception with awareness and a measure that is sensitive to perception without awareness or to demonstrate a qualitative difference between the consequences of perception with and without awareness. Awareness has been controlled either by manipulating the stimulus conditions or by instructing observers on how to distribute their attention. The experimental findings based on all four approaches lead to the same conclusion; namely, stimuli are perceived even when observers are unaware of the stimuli. This conclusion is supported by results of studies in which awareness has been assessed with either objective measures of forced-choice discriminations or measures based on verbalizations of subjective conscious experiences. Given this solid empirical support for the concept of perception without awareness, a direction for future research studies is to assess the functions of information perceived without awareness in determining what is perceived with awareness. The available evidence suggests that information perceived without awareness both biases what stimuli are perceived with awareness and influences how stimuli perceived with awareness are consciously experienced.
6053849
Conscious, preconscious, and subliminal processing: a testable taxonomy
Of the many brain events evoked by a visual stimulus, which are specifically associated with conscious perception, and which merely reflect non-conscious processing? Several recent neuroimaging studies have contrasted conscious and non-conscious visual processing, but their results appear inconsistent. Some support a correlation of conscious perception with early occipital events, others with late parieto-frontal activity. Here we attempt to make sense of these dissenting results. On the basis of the global neuronal workspace hypothesis, we propose a taxonomy that distinguishes between vigilance and access to conscious report, as well as between subliminal, preconscious and conscious processing. We suggest that these distinctions map onto different neural mechanisms, and that conscious perception is systematically associated with surges of parieto-frontal activity causing top-down amplification.
6082151
Affective influences on the attentional dynamics supporting awareness.
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.
142766035
The automaticity of everyday life.
Contents: Preface. J.A. Bargh, The Automaticity of Everyday Life. M.R. Banaji, I.V. Blair, J. Glaser, Environments and Unconscious Processes. R.F. Baumeister, K.L. Sommer, Consciousness, Free Choice, and Automaticity. L. Berkowitz, Some Thoughts Extending Bargh's Argument. C.S. Carver, Associations to Automaticity. G. Clore, T. Ketelaar, Minding Our Emotions: On the Role of Automatic, Unconscious Affect. D. Cohen, Ifs and Thens in Cultural Psychology. W.L. Gardner, J.T. Cacioppo, Automaticity and Social Behavior: A Model, A Marriage and a Merger. C.D. Hardin, A.J. Rothman, Rendering Accessible Information Relevant: The Applicability of Everyday Life. G.D. Logan, The Automaticity of Academic Life: Unconscious Applications of an Implicit Theory. W. Mischel, Was the Cognitive Revolution Just a Detour on the Road to Behaviorism? On the Need to Reconcile Situational Control and Personal Control. E.R. Smith, Preconscious Automaticity in a Modular Connectionist System. T.K. Srull, The Vicissitudes of Social Behavior and Mental Life. J. Tzelgov, Automatic but Conscious: That Is How We Act Most of the Time. J.A. Bargh, Reply to Commentaries.
25848791
Rapid extraction of emotional expression: evidence from evoked potential fields during brief presentation of face stimuli
Although the emotional expression of faces is believed to be accessed rapidly, previous ERP studies hardly found correlates of these processes. Here, we report findings from a study that investigated dichoptic binocular interaction using emotional face stimuli. Thirty-one subjects were briefly presented with schematic normal and scrambled faces (of neutral, positive, or negative expression) that occurred simultaneously in the left and right visual fields. Stimuli for both eyes could be congruent (control) or incongruent (dichoptic). Subjects decided which of the superimposed images in both hemi-fields appeared more "face-like" and during this task, the EEG was recorded from 30 channels. VEPs were analysed topographically according to the influence of the different experimental conditions (defined by presentation form, emotional expression, and location). Behavioural responses to the ambiguous dichoptic stimuli demonstrated a functional eye dominance not related to visual acuity and conventional eye preference. Electrophysiological data revealed three components with mean latencies of 85, 160, and 310 ms. Topography of the second component (equivalent to the face-related N170) differed in left-right and anterior-posterior direction compared with simple checkerboard stimuli. Dichoptic presentation caused reduced field strength of all three, and increased latency of the first component. Faces with negative expression yielded largest field strength of the second and third components. Besides that, emotional expression affected topography not only of late, but also the first component. This provides new evidence about the timing of perceptual processes related to facial expression, indicating that already VEP components occurring at 80-90 ms are sensitive to emotional content.
14654277
Fleeting images: a new look at early emotion discrimination.
The visual brain quickly sorted stimuli for emotional impact despite high-speed presentation (3 or 5 per s) in a sustained, serial torrent of 700 complex pictures. Event-related potentials, recorded with a dense electrode array, showed selective discrimination of emotionally arousing stimuli from less affective content. Primary sources of this activation were over the occipital cortices, extending to right parietal cortex, suggesting a processing focus in the posterior visual system. Emotion discrimination was independent of formal pictorial properties (color, brightness. spatial frequency, and complexity). The data support the hypothesis of a very short-term conceptual memory store (M. C. Potter, 1999)-shown here to include a fleeting but reliable assessment of affective meaning.
67858
Unconscious Facial Reactions to Emotional Facial Expressions
Studies reveal that when people are exposed to emotional facial expressions, they spontaneously react with distinct facial electromyographic (EMG) reactions in emotion-relevant facial muscles. These reactions reflect, in part, a tendency to mimic the facial stimuli. We investigated whether corresponding facial reactions can be elicited when people are unconsciously exposed to happy and angry facial expressions. Through use of the backward-masking technique, the subjects were prevented from consciously perceiving 30-ms exposures of happy, neutral, and angry target faces, which immediately were followed and masked by neutral faces. Despite the fact that exposure to happy and angry faces was unconscious, the subjects reacted with distinct facial muscle reactions that corresponded to the happy and angry stimulus faces. Our results show that both positive and negative emotional reactions can be unconsciously evoked, and particularly that important aspects of emotional face-to-face communication can occur on an unconscious level.
144221800
Detection of emotional faces: low perceptual threshold and wide attentional span
In two experiments, prime face stimuli with an emotional or a neutral expression were presented individually for 25 to 125 ms, either in foveal or parafoveal vision; following a mask, a probe face or a word label appeared for recognition. Accurate detection and sensitivity (A') were higher for angry, happy, and sad faces than for nonemotional (neutral) or novel (scheming) faces at short exposure times (25-75 ms), in both the foveal and the parafoveal field, and with both the probe face and the probe word. These results indicate that there is a low perceptual threshold for unambiguous emotional faces, which are especially likely to be detected both within and outside the focus of attention; and that this facilitated detection involves processing of the affective meaning of faces, not only discrimination of formal visual features.
24659512
Priming of Emotion Recognition
Four experiments investigated priming of emotion recognition using a range of emotional stimuli, including facial expressions, words, pictures, and nonverbal sounds. In each experiment, a prime–target paradigm was used with related, neutral, and unrelated pairs. In Experiment 1, facial expression primes preceded word targets in an emotion classification task. A pattern of priming of emotional word targets by related primes with no inhibition of unrelated primes was found. Experiment 2 reversed these primes and targets and found the same pattern of results, demonstrating bidirectional priming between facial expressions and words. Experiment 2 also found priming of facial expression targets by picture primes. Experiment 3 demonstrated that priming occurs not just between pairs of stimuli that have a high co-occurrence in the environment (for example, nonverbal sounds and facial expressions), but with stimuli that co-occur less frequently and are linked mainly by their emotional category (for example, nonverbal sounds and printed words). This shows the importance of the prime and target sharing a common emotional category, rather than their previous co-occurrence. Experiment 4 extended the findings by showing that there are category-based effects as well as valence effects in emotional priming, supporting a categorical view of emotion recognition.
7595523
Affective priming with subliminally presented pictures.
Affective priming studies have demonstrated that subliminally presented prime words can exert an influence on responses towards positive or negative target stimuli. In the present series of experiments, it was investigated whether these findings can be extended to pictorial stimuli. Ideographically selected positive, neutral, and negative picture primes that were sandwich-masked immediately preceded positive or negative target pictures (Experiment 1) or words (Experiments 2 & 3). Evaluative categorization responses to these target stimuli were significantly influenced by the valence of the prime. First, it was demonstrated that high anxious participants were selectively slowed when the subliminally presented prime was negative (Experiments 1 & 2). Second, the affective congruence between primes and targets also exerted an influence on the responses, but in a direction that is opposite to what is typically observed in affective priming research. These reverse priming effects are situated within a series of recent similar findings, and implications for theories of affective priming are discussed.
16138330
Affect, cognition, and awareness: affective priming with optimal and suboptimal stimulus exposures.
The affective primacy hypothesis (R. B. Zajonc, 1980) asserts that positive and negative affective reactions can be evoked with minimal stimulus input and virtually no cognitive processing. The present work tested this hypothesis by comparing the effects of affective and cognitive priming under extremely brief (suboptimal) and longer (optimal) exposure durations. At suboptimal exposures only affective primes produced significant shifts in Ss' judgments of novel stimuli. These results suggest that when affect is elicited outside of conscious awareness, it is diffuse and nonspecific, and its origin and address are not accessible. Having minimal cognitive participation, such gross and nonspecific affective reactions can therefore be diffused or displaced onto unrelated stimuli. At optimal exposures this pattern of results was reversed such that only cognitive primes produced significant shifts in judgments. Together, these results support the affective primacy hypothesis.
23584456
The processing of emotional facial expression is gated by spatial attention: evidence from event-related brain potentials.
To investigate whether the processing of faces and emotional facial expression can be modulated by spatial attention, ERPs were recorded in response to stimulus arrays containing two faces and two non-face stimuli (houses). In separate trials, attention was focused on the face pair or on the house pair, and facial expression was either fearful or neutral. When faces were attended, a greater frontal positivity in response to arrays containing fearful faces was obtained, starting about 100 ms after stimulus onset. In contrast, with faces located outside the attentional focus, this emotional expression effect was completely eliminated. This differential result demonstrates for the first time a strong attentional gating of brain processes involved in the analysis of emotional facial expression. It is argued that while an initial detection of emotionally relevant events mediated by the amygdala may occur pre-attentively, subsequent stages of emotional processing require focal spatial attention. The face-sensitive N170 component was unaffected by emotional facial expression, but N170 amplitudes were enhanced when faces were attended, suggesting that spatial attention can modulate the structural encoding of faces.
12004324
Effects of Attention and Emotion on Face Processing in the Human Brain An Event-Related fMRI Study
We used event-related fMRI to assess whether brain responses to fearful versus neutral faces are modulated by spatial attention. Subjects performed a demanding matching task for pairs of stimuli at prespecified locations, in the presence of task-irrelevant stimuli at other locations. Faces or houses unpredictably appeared at the relevant or irrelevant locations, while the faces had either fearful or neutral expressions. Activation of fusiform gyri by faces was strongly affected by attentional condition, but the left amygdala response to fearful faces was not. Right fusiform activity was greater for fearful than neutral faces, independently of the attention effect on this region. These results reveal differential influences on face processing from attention and emotion, with the amygdala response to threat-related expressions unaffected by a manipulation of attention that strongly modulates the fusiform response to faces.
14401208
Additive effects of emotional content and spatial selective attention on electrocortical facilitation.
Affectively arousing visual stimuli have been suggested to automatically attract attentional resources in order to optimize sensory processing. The present study crosses the factors of spatial selective attention and affective content, and examines the relationship between instructed (spatial) and automatic attention to affective stimuli. In addition to response times and error rate, electroencephalographic data from 129 electrodes were recorded during a covert spatial attention task. This task required silent counting of random-dot targets embedded in a 10 Hz flicker of colored pictures presented to both hemifields. Steady-state visual evoked potentials (ssVEPs) were obtained to determine amplitude and phase of electrocortical responses to pictures. An increase of ssVEP amplitude was observed as an additive function of spatial attention and emotional content. Statistical parametric mapping of this effect indicated occipito-temporal and parietal cortex activation contralateral to the attended visual hemifield in ssVEP amplitude modulation. This difference was most pronounced during selection of the left visual hemifield, at right temporal electrodes. In line with this finding, phase information revealed accelerated processing of aversive arousing, compared to affectively neutral pictures. The data suggest that affective stimulus properties modulate the spatiotemporal process along the ventral stream, encompassing amplitude amplification and timing changes of posterior and temporal cortex.
10422467
Gaze Patterns When Looking at Emotional Pictures: Motivationally Biased Attention
Pictures of either emotionally neutral, pleasant (affectionate), or unpleasant (threat and injury) scenes were paired with nonemotional control pictures and presented for 3 s, while eye fixations were monitored. Preferential attention to the emotional picture of eah pair occurred at an early processing stage: The probability of placement of the first fixation and the proportion of viewing time during the first 500 ms were higher for both pleasant and unpleasant pictures than for neutral pictures, whereas later fixation location and time were not differentially affected. This suggests that, when emotional and nonemotional stimuli are presented simultaneously, emotional meaning captures initial overt orienting and engages attention early, as measured by gaze direction and duration. The possibility that this effect could be accounted for by perceptual differences—such as luminance and complexity—between emotional and neutral pictures was ruled out.
727848
Eye movement assessment of selective attentional capture by emotional pictures.
The eye-tracking method was used to assess attentional orienting to and engagement on emotional visual scenes. In Experiment 1, unpleasant, neutral, or pleasant target pictures were presented simultaneously with neutral control pictures in peripheral vision under instruction to compare pleasantness of the pictures. The probability of first fixating an emotional picture, and the frequency of subsequent fixations, were greater than those for neutral pictures. In Experiment 2, participants were instructed to avoid looking at the emotional pictures, but these were still more likely to be fixated first and gazed longer during the first-pass viewing than neutral pictures. Low-level visual features cannot explain the results. It is concluded that overt visual attention is captured by both unpleasant and pleasant emotional content.
145705782
From searching for features to searching for threat: Drawing the boundary between preattentive and attentive vision
The distinction between preattentive and attentional processing has been a key element in many theories of attention, but there are conflicting claims as to which functions are performed preattentively, and which require attention. Recent studies suggest that stimuli associated with strong emotions or threat are effective at capturing and/or holding attention. Especially relevant for the question of preattentive vision are search experiments showing that emotional stimuli are sometimes found more quickly than neutral stimuli. An examination of these experiments indicates that there is no evidence that the threatening nature of stimuli is detected preattentively. There is evidence, however, that participants can learn to associate particular features, combinations of features, or configurations of lines with threat, and use them to guide search to threat-related targets. This debate highlights the importance of determining not only what information is encoded preattentively, but how target features that are used to guide search are specified.
55358035
Semantic Processing Precedes Affect Retrieval: The Neurological Case for Cognitive Primacy in Visual Processing
According to the affective primacy hypothesis, visual stimuli can be evaluated prior to and independent of object identification and semantic analysis (Zajonc, 1980, 2000). Our review concludes that the affective primacy hypothesis is, from the available evidence, not likely correct. Although people can react to objects that they cannot consciously identify, such affective reactions are dependent upon prior semantic analysis within the visual cortex. The authors propose that the features of objects must first be integrated, and then the objects themselves must be categorized and identified, all prior to affective analysis. Additionally, the authors offer a preliminary neurological analysis of the mere exposure and affective priming effects that is consistent with the claim that semantic analysis is needed to elicit these effects. In sum, the authors conclude that the brain must know what something is in order to know whether it is good or bad.
42852012
Affective priming with liked and disliked persons: Prime visibility determines congruency and incongruency effects
The present research investigated whether the affective priming paradigm from Fazio, Sanbonmatsu, Powell, and Kardes (1986) can be used as an implicit measure of person schemata. Names and faces of friends or romantic partners and of a disliked person were used as primes. It was explored whether: (1) stimuli relating to liked and disliked persons elicit congruency priming effects similar to those reported for words; (2) masked and unmasked priming procedures had similar effects; and (3) whether individual differences in the implicit measure were related to explicit measures of relationship quality. For clearly visible primes the expected congruence priming effects were found across names and faces. For marginally visible primes, however, unexpected reverse priming effects were observed for the disliked person. In a second experiment, a confound of the familiarity and evaluation of the significant other primes was removed. Now a reverse priming effect could be demonstrated for masked primes in both liked and disliked person conditions. On the group level, effects were consistent across name and face primes, thus providing strong evidence that priming effects were caused by the activation of person schemata. The reliability of inter-individual differences in person-specific priming effects was found to be unsatisfactory, and correlations with explicit measures were not consistent across name and face priming conditions. An explanation of reverse priming effects is discussed, and measures to improve the psychometric quality of individual affective priming indices are suggested.
20819674
Emotional conditioning to masked stimuli: expectancies for aversive outcomes following nonrecognized fear-relevant stimuli.
The role of conscious awareness in human Pavlovian conditioning was examined in 2 experiments using masked fear-relevant (snakes and spiders; Experiments 1 and 2) and fear-irrelevant (flowers and mushrooms; Experiment 1) pictures as conditioned stimuli, a mild electric shock as the unconditioned stimulus, and skin conductance responses as the primary dependent variable. The conditioned stimuli were presented briefly (30 ms) and were effectively masked by an immediately following masking stimulus. Experiment 1 demonstrated nonconscious conditioning to fear-relevant but not to fear-irrelevant stimuli. Even though the participants could not recognize the stimuli in Experiment 2, they differentiated between masked stimuli predicting and not predicting shocks in expectancy ratings. However, expectancy ratings were not related to the conditioned autonomic response.
145611462
The affective priming effect: Automatic activation of evaluative information in memory.
Abstract Fazio, Sanbonmatsu, Powell, and Kardes (1986) argued that affect may be activated automatically from memory on the mere observation of an affect-loaded stimulus. Using a variant of the standard sequential priming paradigm, it was demonstrated that the time needed to evaluate target words as positive or negative decreased if they were preceded by a similarly valenced prime word, but increased when preceded by a prime of opposite valence. Several aspects of their procedure, however, do not warrant their conclusion concerning the unconditionality of the effect. The present research investigated the generality of this affective priming effect. In Experiment 1, it was tested whether the effect can be generalised to more complex visual material. Stimulus pairs consisted of colour slides. Subjects had to evaluate the targets as quickly as possible. In Experiment 2, the standard word-word procedure was used, but target words had to be pronounced. In both experiments, significant affective priming effects...
603417
Are affective events richly recollected or simply familiar? The experience and process of recognizing feelings past.
The author used the remember/know paradigm and the dual process recognition model of A. P. Yonelinas, N. E. A. Kroll, I. Dobbins, M. Lazzara, and R. T. Knight (1998) to study the states of awareness accompanying recognition of affective images and the processes of recollection and familiarity that may underlie them. Results from all experiments showed that (a) negative stimuli tended to be remembered, whereas positive stimuli tended to be known; (b) recollection, but not familiarity, was boosted for negative or highly arousing and, to a lesser extent, positive stimuli; and (c) across experiments, variations in depth of encoding did not influence these patterns. These data suggest that greater recollection for affective events leads them to be more richly experienced in memory, and they are consistent with the idea that the states of remembering and knowing are experientially exclusive, whereas the processes underlying them are functionally independent.
7655689
Spatial frequency, phase, and the contrast of natural images.
We examined contrast sensitivity and suprathreshold apparent contrast with natural images. The spatial-frequency components within single octaves of the images were removed (notch filtered), their phases were randomized, or the polarity of the images was inverted. Of Michelson contrast, root-mean-square (RMS) contrast, and band-limited contrast, RMS contrast was the best index of detectability. Negative images had lower apparent contrast than their positives. Contrast detection thresholds showed spatial-frequency-dependent elevation following both notch filtering and phase randomization. The peak of the spatial-frequency tuning function was approximately 0.5-2 cycles per degree (c/deg). Suprathreshold contrast matching functions also showed spatial-frequency-dependent contrast loss for both notch-filtered and phase-randomized images. The peak of the spatial-frequency tuning function was approximately 1-3 c/deg. There was no detectable difference between the effects of phase randomization and notch filtering on contrast sensitivity. We argue that these observations are consistent with changes in the activity within spatial-frequency channels caused by the higher-order phase structure of natural images that is responsible for the presence of edges and specularities.
1434077
Contrast in complex images.
The physical contrast of simple images such as sinusoidal gratings or a single patch of light on a uniform background is well defined and agrees with the perceived contrast, but this is not so for complex images. Most definitions assign a single contrast value to the whole image, but perceived contrast may vary greatly across the image. Human contrast sensitivity is a function of spatial frequency; therefore the spatial frequency content of an image should be considered in the definition of contrast. In this paper a definition of local band-limited contrast in images is proposed that assigns a contrast value to every point in the image as a function of the spatial frequency band. For each frequency band, the contrast is defined as the ratio of the bandpass-filtered image at the frequency to the low-pass image filtered to an octave below the same frequency (local luminance mean). This definition raises important implications regarding the perception of contrast in complex images and is helpful in understanding the effects of image-processing algorithms on the perceived contrast. A pyramidal image-contrast structure based on this definition is useful in simulating nonlinear, threshold characteristics of spatial vision in both normal observers and the visually impaired.
29922646
Preferences and Inferences in Encoding Visual Objects: A Systematic Comparison of Semantic and Affective Priming
The authors systematically compared semantic and affective priming in five studies involving words and pictures. In Studies 1 (lexical decision task) and 2 (evaluation task), irrelevant short duration (200 ms) primes were briefly flashed before relevant targets. The authors orthogonally varied both the semantic and affective relations between primes and targets. In both studies, semantic priming but not affective priming was found. Study 3 revealed that the same stimuli can produce affective priming, but only when words come from a single semantic category. Studies 4 and 5 used pictures rather than words to examine automatic encoding tendencies. The results conceptually replicated those from Studies 1 and 2. In sum, the findings suggest that affective priming may be a relatively fragile phenomenon, particularly when the semantic properties of objects vary in a salient manner.
25001771
Identification facilitation for emotionally arousing verbs during the attentional blink.
The present study aimed to examine affective modulation of the "attentional blink" effect during rapid serial visual presentation (RSVP). Pleasant, neutral, and unpleasant written verbs were used as a 2nd target (T2) in an 8.6-Hz RSVP paradigm. Pronounced effects of 1st target (T1)-T2 stimulus onset asynchrony (SOA) were found, showing reduced report accuracy for 232- and 464-ms SOAs. Affectively arousing (pleasant and unpleasant) T2s were associated with enhanced accuracy compared with neutral T2s specifically during short (232 ms) SOAs. In contrast, pleasant and unpleasant T2s rated low in terms of emotional arousal did not show this enhancement. These results suggest that affectively arousing information is selected preferentially from a temporal stream, facilitating processes such as working memory consolidation and action.
6711408
Attentional interference effects of emotional pictures: threat, negativity, or arousal?
Attentional interference arising from emotional pictures was examined. Participants had to ignore emotional pictures while solving math problems (Study 1, N = 126) or detecting the location of a line (Study 2, N = 60). Data analyses tested predictions of 3 theories. Evolutionary threat theory predicts interference by snake pictures. Categorical negativity theory predicts interference by negative pictures regardless of their intensity. According to arousal theory, arousal level predicts interference effects. The results supported arousal theory, with the most arousing pictures (strong unpleasant pictures, oppositesex models) producing the strongest interference. The findings are interpreted in the context of process models of emotions that postulate an initial relevance check before further processing of valence and other appraisal dimensions.
17663354
Automatic non-associative semantic priming: episodic affective priming of naming responses.
Affective priming for associatively unrelated prime-target pairs was investigated using (a) the naming task, (b) a short stimulus onset asynchrony (250 ms), and (c) primes that had acquired their affective connotation during a differential evaluative conditioning procedure. Despite the fact that the primes and the targets were related on the affective dimension only, significant priming emerged. This finding indicates that mere affective overlap is sufficient to produce automatic priming. As such, our results are in line with theoretical accounts of automatic priming that are based on semantic relatedness.
18139136
Distracted and confused?: Selective attention under load
The ability to remain focused on goal-relevant stimuli in the presence of potentially interfering distractors is crucial for any coherent cognitive function. However, simply instructing people to ignore goal-irrelevant stimuli is not sufficient for preventing their processing. Recent research reveals that distractor processing depends critically on the level and type of load involved in the processing of goal-relevant information. Whereas high perceptual load can eliminate distractor processing, high load on "frontal" cognitive control processes increases distractor processing. These findings provide a resolution to the long-standing early and late selection debate within a load theory of attention that accommodates behavioural and neuroimaging data within a framework that integrates attention research with executive function.
2643153
How brains beware: neural mechanisms of emotional attention
Emotional processes not only serve to record the value of sensory events, but also to elicit adaptive responses and modify perception. Recent research using functional brain imaging in human subjects has begun to reveal neural substrates by which sensory processing and attention can be modulated by the affective significance of stimuli. The amygdala plays a crucial role in providing both direct and indirect top-down signals on sensory pathways, which can influence the representation of emotional events, especially when related to threat. These modulatory effects implement specialized mechanisms of 'emotional attention' that might supplement but also compete with other sources of top-down control on perception. This work should help to elucidate the neural processes and temporal dynamics governing the integration of cognitive and affective influences in attention and behaviour.
42824967
Right hemisphere lateralization for emotion in the human brain: interactions with cognition
Right-handed subjects tend to look to the left when answering affective questions. The relative shift in gaze from right to left is accentuated when the questions also involve spatial manipulation and attenuated when the questions require verbal manipulation. The data support the hypothesis that the right hemisphere has a special role in emotion in the intact brain, and that predictable patterning of hemispheric activity can occur when specific combinations of cognitive and affective processes interact.
8853363
Cortical Systems for the Recognition of Emotion in Facial Expressions
This study is part of an effort to map neural systems involved in the processing of emotion, and it focuses on the possible cortical components of the process of recognizing facial expressions. We hypothesized that the cortical systems most responsible for the recognition of emotional facial expressions would draw on discrete regions of right higher-order sensory cortices and that the recognition of specific emotions would depend on partially distinct system subsets of such cortical regions. We tested these hypotheses using lesion analysis in 37 subjects with focal brain damage. Subjects were asked to recognize facial expressions of six basic emotions: happiness, surprise, fear, anger, disgust, and sadness. Data were analyzed with a novel technique, based on three-dimensional reconstruction of brain images, in which anatomical description of surface lesions and task performance scores were jointly mapped onto a standard brain-space. We found that all subjects recognized happy expressions normally but that some subjects were impaired in recognizing negative emotions, especially fear and sadness. The cortical surface regions that best correlated with impaired recognition of emotion were in the right inferior parietal cortex and in the right mesial anterior infracalcarine cortex. We did not find impairments in recognizing any emotion in subjects with lesions restricted to the left hemisphere. These data provide evidence for a neural system important to processing facial expressions of some emotions, involving discrete visual and somatosensory cortical sectors in right hemisphere.
22212468
Right hemisphere emotional perception: evidence across multiple channels.
Emotional perception was examined in stroke patients across 3 communication channels: facial, prosodic, and lexical. Hemispheric specialization for emotion was tested via right-hemisphere (RH) and valence hypotheses, and relationships among channels were determined. Participants were 11 right-brain-damaged (RBD), 10 left-brain-damaged (LBD), and 15 demographically matched normal control (NC) adults. Experimental measures, with analogous psychometric properties, were identification and discrimination tasks, including a range of positive and negative emotions. Nonemotional control tasks were used for each channel. For identification, RBDs were significantly impaired relative to LBDs and NCs across channels and valences, supporting the RH hypothesis. No group differences emerged for discrimination. Findings were not influenced by demographic, clinical, or control variables. Correlations among the channels were more prominent for normal than for brain-damaged groups.
8897909
Functional neuroanatomy of emotions: A meta-analysis
The application of functional neuroimaging to the study of human emotion has yielded valuable data; however, the conclusions that may be drawn from any one study are limited. We applied novel statistical techniques to the meta-analysis of 106 PET and fMRI studies of human emotion and tested predictions made by key neuroscientific models. The results demonstrated partial support for asymmetry accounts. Greater left-sided activity was observed for approach emotions, whereas neural activity associated with negative/withdrawal emotions was symmetrical. Support was also found for affect program emotion accounts. The activation distributions associated with fear, disgust, and anger differed significantly. These emotions were most consistently associated in activity in regions associated with selective processing deficits when damaged: the amygdala, the insula and globus pallidus, and the lateral orbitofrontal cortex, respectively. In contrast, the distributions for happiness and sadness did not differ. These findings are considered in the context of conceptualizations of the neural correlates of human emotion.
16142704
Emotional arousal and activation of the visual cortex: an fMRI analysis.
Functional activity in the visual cortex was assessed using functional magnetic resonance imaging technology while participants viewed a series of pleasant, neutral, or unpleasant pictures. Coronal images at four different locations in the occipital cortex were acquired during each of eight 12-s picture presentation periods (on) and 12-s interpicture interval (off). The extent of functional activation was larger in the right than the left hemisphere and larger in the occipital than in the occipitoparietal regions during processing of all picture contents compared with the interpicture intervals. More importantly, functional activity was significantly greater in all sampled brain regions when processing emotional (pleasant or unpleasant) pictures than when processing neutral stimuli. In Experiment 2, a hypothesis that these differences were an artifact of differential eye movements was ruled out. Whereas both emotional and neutral pictures produced activity centered on the calcarine fissure (Area 17), only emotional pictures also produced sizable clusters bilaterally in the occipital gyrus, in the right fusiform gyrus, and in the right inferior and superior parietal lobules.
6543623
Activation of the visual cortex in motivated attention.
Functional activation (measured with fMRI) in occipital cortex was more extensive when participants view pictures strongly related to primary motive states (i.e., victims of violent death, viewer-directed threat, and erotica). This functional activity was greater than that observed for less intense emotional (i.e., happy families or angry faces) or neutral images (i.e., household objects, neutral faces). Both the extent and strength of functional activity were related to the judged affective arousal of the different picture contents, and the same pattern of functional activation was present whether pictures were presented in color or in grayscale. It is suggested that more extensive visual system activation reflects "motivated attention," in which appetitive or defensive motivational engagement directs attention and facilitates perceptual processing of survival-relevant stimuli.
7873788
Common effects of emotional valence, arousal and attention on neural activation during visual processing of pictures
Emotion and attention heighten sensitivity to visual cues. How neural activation patterns associated with emotion change as a function of the availability of attentional resources is unknown. We used positron emission tomography (PET) and 15O-water to measure brain activity in male volunteers while they viewed emotional picture sets that could be classified according to valence or arousal. Subjects simultaneously performed a distraction task that manipulated the availability of attentional resources. Twelve scan conditions were generated in a 3 x 2 x 2 factorial design involving three levels of valence (pleasant, unpleasant and neutral), two levels of arousal and two levels of attention (low and high distraction). Extrastriate visual cortical and anterior temporal areas were independently activated by emotional valence, arousal and attention. Common areas of activation derived from a conjunction analysis of these separate activations revealed extensive areas of activation in extrastriate visual cortex with a focus in right BA18 (12, -88, -2) (Z=5.73, P < 0.001 corrected) and right anterior temporal cortex BA38 (42, 14, -30) (Z=4.03, P < 0.05 corrected). These findings support an hypothesis that emotion and attention modulate both early and late stages of visual processing.
145360726
The involvement of distinct visual channels in rapid attention towards fearful facial expressions
This paper reports five experiments demonstrating that the low spatial frequency components of faces are critical to the production of rapid attentional responses towards fearful facial expressions. In our main experiments, low spatial frequency (LSF) or high spatial frequency (HSF) face pairs, consisting of one fearful and one neutral expression, were presented on a computer screen for a brief period. Participants were required to identify as quickly as possible the orientation of a bar target that immediately replaced one of the faces. Responses were faster when targets replaced the location of LSF fearful faces, compared with LSF neutral faces. By contrast, there were no differences between responses to targets replacing HSF fearful versus HSF neutral faces. This facilitation in spatial orienting occurred specifically with short time intervals between faces and target, and is consistent with a rapid processing of fear cues from LSF inputs that can serve to guide attention towards threat events.
73533083
Processing of “unattended” threat-related information: Role of emotional content and context
Unpleasant, pleasant, or neutral visual scenes served as a context for the presentation of threat-related, positive, and neutral words. On each trial, 2 simultaneous prime words (one foveal, i.e., at fixation, and one parafoveal, i.e., 2.2° apart) appeared for 150 ms, followed by a foveally presented probe word in a lexical decision task. Results showed facilitation in response times for probe threat words when primed by an identical parafoveal word, in comparison with priming by an unrelated parafoveal word, and this effect was enhanced in an emotionally congruent unpleasant context. In contrast, no parafoveal effect appeared for positive words, even in a pleasant context. This reveals parallel processing of threat-related words outside the focus of attention.
2268569
Is emotional content obtained from parafoveal words during reading? An eye movement analysis.
An eye-movement-contingent display change technique was employed to study whether adult readers extract semantic information from parafoveal words during reading. Three types of parafoveal preview conditions were contrasted: an emotional word, a neutral word, and an identical word condition. To have a maximally effective parafoveal manipulation, high-arousal emotional words (sex- and threat-related and curse words) were used as parafoveal previews. Readers' eye fixation patterns around the target word revealed no evidence for parafoveal semantic processing. Furthermore, the pupil size showed no signs for an emotional response triggered by an emotional word previewed parafoveally. These results are consistent with the view that, as a rule, only the fixated word is processed to a semantic level during reading.
38332364
Word frequency and laterality effects in lexical decision: Right hemisphere mechanisms
Three experiments investigated the role of the right cerebral hemisphere in the word frequency effect observed in visual word recognition. The experiments examined lexical decisions to low and high frequency words as well as non-words in a divided visual field paradigm. Experiment 1 showed a significant word frequency effect only for left visual field presentation. Experiment 2 provided a partial replication of the results of Experiment 1 with a different set of words. In Experiment 3, case alternation was implemented to investigate a possible explanation of the findings. Results of the first experiment were replicated in the condition without case alternation. In the case-alternated condition, the word frequency effect was significant only for right visual field presentations. The present findings emphasize the need to consider that information processing strategies relevant to hemispheric asymmetries might account in part for the word frequency effect.
32317403
The face in the crowd revisited: a threat advantage with schematic stimuli.
Schematic threatening, friendly, and neutral faces were used to test the hypothesis that humans preferentially orient their attention toward threat. Using a visual search paradigm, participants searched for discrepant faces in matrices of otherwise identical faces. Across 5 experiments, results consistently showed faster and more accurate detection of threatening than friendly targets. The threat advantage was obvious regardless of whether the conditions favored parallel or serial search (i.e., involved neutral or emotional distractors), and it was valid for inverted faces. Threatening angry faces were more quickly and accurately detected than were other negative faces (sad or "scheming"), which suggests that the threat advantage can be attributed to threat rather than to the negative valence or the uniqueness of the target display.
15124907
Emotional facial expressions capture attention
Objective: To determine whether the emotional significance of stimuli can influence spatial attention. Background: Motivational and emotional factors may affect attention toward stimuli. However, this has never been examined in brain-damaged patients who present with unilateral inattention due to left spatial neglect. Methods: The authors studied three patients with chronic left neglect and visual extinction after right parietal stroke. Shapes or faces with neutral, happy, or angry expressions were briefly presented in the right, left, or both visual fields. On unilateral trials, the patients detected all stimuli equally on both sides. On bilateral trials, they extinguished faces in the contralesional field much less often than shapes, and faces with happy or angry facial expressions much less than faces with a neutral expression. Conclusion: Facial features and emotional expressions can be analyzed despite lying on the unattended side, and may influence the spatial distribution of attention. These findings support the view that attention is controlled by neural mechanisms involving not only frontoparietal areas but also limbic components in cingulate cortex and amygdala, which may interact with ventral visual areas in the temporal lobe to detect affective value and prioritize attention to salient stimuli.
9117711
Neural processing of emotional faces requires attention
Attention gates the processing of stimuli relatively early in visual cortex. Yet, existing data suggest that emotional stimuli activate brain regions automatically, largely immune from attentional control. To resolve this puzzle, we used functional magnetic resonance imaging to first measure activation in regions that responded differentially to faces with emotional expressions (fearful and happy) compared with neutral faces. We then measured the modulation of these responses by attention, using a competing task with a high attentional load. Contrary to the prevailing view, all brain regions responding differentially to emotional faces, including the amygdala, did so only when sufficient attentional resources were available to process the faces. Thus, the processing of facial expression appears to be under top-down control.
17566356
The role of spatial attention in the processing of facial expression: An ERP study of rapid brain responses to six basic emotions
To investigate the time course of emotional expression processing, we recorded ERP responses to stimulus arrays containing neutral versus angry, disgusted, fearful, happy, sad, or surprised faces. In one half of the experiment, the task was to discriminate emotional and neutral facial expressions. Here, an enhanced early frontocentral positivity was elicited in response to emotional as opposed to neutral faces, followed by a broadly distributed positivity and an enhanced negativity at lateral posterior sites. These emotional expression effects were very similar for all six basic emotional expressions. In the other half of the experiment, attention was directed away from the faces toward a demanding perceptual discrimination task. Under these conditions, emotional expression effects were completely eliminated, demonstrating that brain processes involved in the detection and analysis of facial expression require focal attention. The face-specific N170 component was unaffected by any emotional expression, supporting the hypothesis that structural encoding and expression analysis are independent processes.