On the automaticity of emotion processing in words and faces: event-related brain potentials evidence from a superficial task

The degree to which emotional aspects of stimuli are processed automatically is controversial. Here, we assessed the automatic elicitation of emotion-related brain potentials (ERPs) to positive, negative, and neutral words and facial expressions in an easy and superficial face-word discrimination task, for which the emotional valence was irrelevant. Both emotional words and facial expressions impacted ERPs already between 50 and 100 ms after stimulus onset, possibly reflecting rapid relevance detection. Following this initial processing stage only emotionality in faces but not in words was associated with an early posterior negativity (EPN). Therefore, when emotion is irrelevant in a task which requires superficial stimulus analysis, automatically enhanced sensory encoding of emotional content appears to occur only for evolutionary prepared emotional stimuli, as reflected in larger EPN amplitudes to faces, but not to symbolic word stimuli.     

The effect of arousal on memory for emotionally-relevant information: a study of skydivers

The aim of the present study was to test memory for information under conditions of extreme arousal in an analogue design to mimic hyperarousal during trauma exposure. Prior to their skydive, 70 novice skydivers were administered measures of fear, heart rate, and anxiety sensitivity. Half the participants learnt a list of words that varied in both relevance to their skydive and valence (irrelevant/relevant, negative/neutral) on the plane (skydivers), and remaining participants learnt an identical list of words on the ground (delayed controls). Following the skydive, participants completed free recall and recognition tasks; heart rate, dissociation, and subjective arousal were also measured. Consistent with an attentional narrowing hypothesis, skydivers recalled comparable a comparable number of relevant words as delayed controls, but significantly less irrelevant words. In terms of recognition performance, skydivers displayed better recognition of relevant words but poorer recognition of irrelevant words than delayed controls. Valence of words did not alter the pattern of results. The implications of the findings are discussed in the context of understanding memory processes under conditions of high threat.     

Right hemisphere superiority in the recognition of famous faces

Words and famous faces were tachistoscopically presented in bilateral view to normal right-handed subjects. A left visual field advantage was obtained for famous faces whether naming or recognition from an array was required and a right visual field advantage was obtained for words. While the finding of a left visual field advantage for the recognition of famous faces is consistent with studies of face recognition deficits in brain-damaged patients, a right visual field advantage for the recognition of famous faces has recently been reported in normal subjects. Possible explanations for this discrepancy are discussed.     

Updating the contents of working memory in depression: interference from irrelevant negative material

This study was designed to assess the effects of irrelevant emotional material on the ability to update the contents of working memory in depression. For each trial, participants were required to memorize 2 lists of emotional words and subsequently to ignore 1 of the lists. The impact of irrelevant emotional material on the ability to update the contents of working memory was indexed by response latencies on a recognition task in which the participants decided whether or not a probe was a member of the relevant list. The authors compared response latencies to probes from the irrelevant list to response latencies to novel probes of the same valence (intrusion effect). The results indicate that, compared to control participants in both neutral and sad mood states, depressed participants showed greater intrusion effects when presented with negative words. In an important finding, intrusion effects for negative words were correlated with self-reported rumination. These findings indicate that depression is associated with difficulties removing irrelevant negative material from working memory. Results also indicate that the increased interference from irrelevant negative material is associated with rumination.     

Carryover of scanning behaviour affects upright face recognition differently to inverted face recognition

Face perception is characterized by a distinct scanpath. While eye movements are considered functional, there has not been direct evidence that disrupting this scanpath affects face recognition performance. The present experiment investigated the influence of an irrelevant letter-search task (with letter strings arranged horizontally, vertically, or randomly) on the subsequent scanning strategies in processing upright and inverted famous faces. Participants’ response time to identify the face and the direction of their eye movements were recorded. The orientation of the letter search influenced saccadic direction when viewing the face images, such that a direct carryover-effect was observed. Following a vertically oriented letter-search task, the recognition of famous faces was slower and less accurate for upright faces, and faster for inverted faces. These results extend the carryover findings of Thompson and Crundall into a novel domain. Crucially they also indicate that upright and inverted faces are better processed by different eye movements, highlighting the importance of scanpaths in face recognition.     

Conditions of directed attention inhibit recognition performance for explicitly presented target-aligned irrelevant stimuli

The fate of irrelevant and overtly presented stimuli that was temporally aligned with an attended target in a separate task was explored. Seitz and Watanabe (2003) demonstrated that if an irrelevant motion stimulus was implicit (i.e., subthreshold), a later facilitation for the same motion direction was observed if the previously presented implicit motion (of the same direction) was temporally aligned with the presence of an attended target. Later research, however, demonstrated that if the motion stimulus aligned with the attended target was explicit (i.e., suprathreshold), a later inhibition was observed (Tsushima, Seitz, & Watanabe, 2008). The current study expands on this by using more salient stimuli (words and pictures) in an inattentional blindness paradigm, and suggests that when attention is depleted, recognition for target-aligned task-irrelevant items is impaired in a subsequent recognition task. Participants were required to respond to either immediate picture, or word, repetitions in a stream of simultaneously presented line drawings and written words, and later given a surprise recognition test that measured recognition for the words or the pictures. When analyzing word recognition performance after attention had been directed to the pictures, words that had appeared simultaneously with a picture repetition in the repetition detection task were recognized at levels significantly below chance. The same inhibition was mirrored when testing for picture recognition after having attended to the words in the repetition detection task. These data suggest an inhibitory mechanism that is exhibited in later recognition tests for salient information that was previously unattended and had been simultaneously being presented with an attended target in a different task.     

Word recognition and face recognition following posterior cerebral artery stroke: Overlapping networks and selective contributions

It has been suggested that word- and face recognition rely on a common cerebral network for perceptual processing. To further explore this hypothesis, face- and word recognition were assessed in seven patients with focal lesions after stroke of the posterior cerebral artery in either hemisphere. The aim was to investigate if problems in face- and word recognition would co-occur, if testing was sensitive and patients were not pre-selected based on behavioural symptoms. Patients and matched controls were given a reading test and a delayed matching paradigm with faces, objects, and words. Interestingly, all patients with word recognition difficulties had problems in face recognition, independently of the affected hemisphere, supporting the existence of a bilateral perceptual network for faces and words. However, two patients showed selective face recognition problems after unilateral damage to either hemisphere, suggesting that parts of this network may be more critical for face than for word recognition.     

Nonreaders' awareness of the basic relationship between spoken and written words

One hundred children, in four groups, were presented with 72 word pairs (spoken and written). Each pair consisted of one short and one long word. The subjects were requested to indicate a target word on a card and explain their choice. The basis for a correct nonreading solution was attention to the surface aspects of words and recognition of the relation between sound duration and number of graphemes. A main experimental variable was the relationship between number of graphemes and the size of the denoted object. In the youngest age group (4-year-olds) irrelevant and nonlinguistic solutions predominated. Older children were guided by semantic content. Proper understanding of the relationship between spoken and written words was observed among some of the oldest children (7-year-olds).     

Massed versus distributed exposure and imaging of faces: Changing the test view

This research examined the effects of massed versus distributed exposure and imaging of faces, and the effects of changing the study-to-test view on subsequent recognition performance. The massed procedure consisted of individual faces exposed once for 6 s, followed by a 30 s off period. The distributed procedure consisted of faces exposed three times for 2 s, followed by a 10 s off period after each exposure. During the off periods, groups of participants either imaged the previous face, imaged another face, or performed an irrelevant letter-search task. Results showed that distributed exposure and post-exposure imaging of target faces facilitated recognition, but these effects primarily occurred when the same facial view was given at both study and test. Recognition diminished when the target was presented in a different view at test, but when combined with distributed presentation and target imaging, performance was enhanced. Implications for suspect identification and recognition of other kinds of complex visual stimuli are discussed.     

Searching for politicians: An information-processing approach to face recognition

Previous work on face recognition has concentrated on the processing of unfamiliar faces. This paper examines the recognition of already familiar faces, specifically politicians. Three experiments are described in which the subject's task was to search through a series of faces for particular target politicians. In Experiment I the function relating search time to target set size was found to be negatively accelerated. A similar function was observed when names were used as search items. In Experiment II all subjects searched for four targets, and the relationship between distractors and target items was varied. Distractors rated visually similar to the targets took longer to reject than those rated dissimilar. Distractors who were other politicians took longer to reject than actors, and this effect of semantic category was independent of visual similarity. In Experiment III, where subjects searched for a single target, semantic category appeared only to have an effect when the distractors were also visually similar to the target. Models of the rejection process are discussed, and the similarities between the effects observed here, with faces, and those reported elsewhere for words are pointed out.     

中文词汇加工过程中的无关言语效应

通过两个词汇识别任务,考察词汇加工过程中的无关言语效应。实验1采用真假词判断任务,考察有意义言语、无意义言语、白噪音和安静的背景声音对不同具体性的词汇识别的影响。结果发现,仅有意义言语干扰了词汇识别,且主要体现在对低具体性词汇判断的反应时显著增加。实验2采用了语义范畴判断任务,同样发现有意义言语条件下被试的反应时显著大于其他声音条件。结果表明,中文词汇加工过程中存在无关言语效应,且当任务强调语义加工时,干扰主要源于无关言语的语义成分,支持了语义干扰假说。     

Oh, it's you again: memory interference from irrelevant emotional and neutral faces

In two experiments, repeated runs of a continuous recognition task were employed to assess healthy participants' ability to handle interference from irrelevant emotional and neutral memories. Presumably, such interference can be due to salience from either emotional or mnemonic processing. In both experiments, participants made more false alarms to emotional faces that were familiar from preceding runs (i.e., emotion-induced temporal-context confusion). Participants performed well for neutral faces in the first experiment including only two runs. However, increasing the number of runs to four in the second experiment induced temporal context confusion also for neutral faces. The findings suggest that memory interference can be induced when the salience of irrelevant information is erroneously considered diagnostic for memory judgements.     

Inhibition is picky: Shape difference is a necessary condition for attentional inhibition of irrelevant objects

The present study investigated the conditions for attentional amplification in the processing of relevant objects and for attentional inhibition in the processing of irrelevant objects. Participants reported the color of one of two superimposed objects that was specified by occlusion. Irrelevant color words were presented as part of the relevant object, as part of the irrelevant object, or in the background; the words were either congruent or incongruent with the color of the relevant object. The size of the congruency effects provided a measure of the (relative) strength of the processing of the objects and the background. Finally, the two objects had the same shape in one session and different shapes in another session. In both sessions, results showed larger Stroop effects from words belonging to the relevant object than from words in the background, indicating attentional amplification of the relevant object that was unaffected by object similarity. In contrast, smaller Stroop effects from words belonging to the irrelevant object than from words in the background occurred only when the two objects differed in shape. The latter result suggests that a shape difference is both a necessary and a sufficient condition for inhibiting the processing of an irrelevant visual object.     

The role of stimulus type in list length effects in recognition memory

While many studies have investigated the list length effect in recognition memory, few have done so with stimuli other than words. This article presents the results of four list length experiments that involved word pairs, faces, fractals, and photographs of scenes as the stimuli. A significant list length effect was identified when faces and fractals were the stimuli, but the effect was nonsignificant when the stimuli were word pairs or photographs of scenes. These findings suggest that the intrastimulus similarity is what dictates whether list length has a significant effect on recognition performance. As is the case with words, word pairs and photographs of scenes are not sufficiently similar to generate detectable item interference.     

Modeling the effects of verbal and nonverbal pair strength on associative recognition

Operations that improve the accuracy of associative recognition can do so in qualitatively different ways. Increasing repetitions and study time increases hit rates but has small effects on false alarm rates, and the specific patterns of false alarms are dependent on the stimuli (e.g., pairs of words, pseudowords, faces, or Chinese characters). In contrast, manipulating the type of stimuli that make up pairs produces a robust mirror effect: The hit rate is greater, and the false alarm rate is lower, for better recognized stimuli. To explain these findings, a model of single-item recognition is extended to associative recognition. Within this dual-process framework, the present results suggest that words are encoded more extensively than nonverbal stimuli and that recognition of frequently encountered stimuli (words and faces) is more likely to be based on recollection than is recognition of uncommon stimuli (pseudowords and Chinese characters).     

The role of spurious feature familiarity in recognition memory

In two experiments, we investigated the role of perceptual information in spurious recognition judgments. Participants viewed lists of words in various unusual fonts. The frequency with which each font was presented was manipulated at study: Each font was presented with 1 or 12 different words in Experiment 1 and with 1 or 20 words in Experiment 2. Although the participants were instructed in a word recognition test to judge only on the basis of the word, regardless of font, there were significantly more false alarms for new words seen in a previously presented font than for new words presented in a novel (not seen at study) font in Experiment 1. In Experiment 2, the participants were significantly more likely to make a false alarm to a new word seen in a font that had been used to present 20 words during study than to a font that had been used to present only 1 word during study. The data show a mirror effect, in which words tested in low-frequency fonts produced more hits and fewer false alarms than did words tested in high-frequency fonts. These results show that irrelevant perceptual information plays a role in recognition judgments by providing spurious sources of familiarity and, thus, provide evidence that perceptual information is represented and processed in the same way as semantic information.     

Visual object agnosia without prosopagnosia or alexia: Evidence for hierarchical theories of visual recognition

Abstract

A single case study is presented of a patient, Mr. W, with a selective deficit in recognizing pictures and real objects, linked to impaired stored visual knowledge about objects. Despite this, Mr. W maintained a preserved ability both to read aloud printed words and to recognize famous faces, when compared with age-matched control subjects. In addition, his access to semantic information from words was superior to that from pictures. The data provide evidence that visual agnosia can occur without alexia or prosopagnosia, contrary to recent proposals (Farah 1990, 1991). This finding is consistent with a hierarchical model of visual object recognition in which agnosia can reflect impaired stored knowledge of objects without accompanying perceptual deficits. The selective recognition deficit for objects further indicates that stored knowledge concerning different classes of visual stimuli (common objects, faces, and words) is separately represented in the brain.     

What happens to information to be suppressed in working-memory tasks? Short and long term effects

The study explored, from an individual differences point of view, what happens to information to be suppressed in a working-memory task at short and long term. In particular, it was examined whether control mechanisms of irrelevant information in working memory imply their complete elimination from working memory or just the modulation of their activation. To this end, we compared the fate of irrelevant information in groups of subjects with high and low reading comprehension (Experiments 1 and 2) and subjects with high and low working memory (Experiments 1, 2, 3, and 4). All the experiments presented a working-memory task devised by De Beni, Palladino, Pazzaglia, and Cornoldi (1998), which required participants to process lists of words, to tap when a word from a particular category was presented, and then to recall only the last items in each list. Results confirmed that participants with high reading comprehension also have higher working memory and make less intrusion errors due to irrelevant items that have to be processed but then discarded. Furthermore, it was found that participants with low working memory have slightly better implicit (Experiment 1) and explicit memory (Experiments 3 and 4) of highly activated irrelevant information. Nevertheless, in a long-term recognition test, participants with high and low reading comprehension/working memory presented a similar pattern of memory for different types of irrelevant information (Experiment 2), whereas in a short-term memory recognition test, low-span participants presented a facilitation effect in the time required for the recognition of highly activated irrelevant information (Experiment 4). It was concluded that efficient working-memory performance is related to the temporary reduction of activation of irrelevant information but does not imply its elimination from memory.     

When context hinders! Learn-test compatibility in face recognition

Some theories of holistic face processing propose that parts in faces (eyes, nose, mouth, etc.) are not explicitly represented. So far, the empirical evidence has shown that whole-to-part superiority is found when wholes are learned. We substantiated this using photographic faces. More importantly, we investigated whether learning parts also reveals holistic effects. This has not been attempted before. Four experiments showed that after learning facial parts, recognition of these parts was disrupted when the part was shown in the full face. This distraction effect was strongest when perceivers were not directed to focus on a particular facial feature. Thus, it is very difficult to ignore irrelevant parts in faces. In fact, this might be the essence of holistic face processing.     

The effect of orienting tasks on recognition memory

The effect of orienting tasks on recognition memory for words and faces was investigated. It was found that relevant orienting tasks improved recognition memory for both classes of stimuli compared with a nonrelevant orienting task and the control condition of testing recognition memory without an orienting task. Attention is drawn to the possibility of qualitative differences between recall and recognition for the effect of orienting tasks. The findings are related to recognition theories. It is suggested that the findings lend support to those theories which hold that retrieval processes play a major role in recognition memory.