unconscious, preattentive influences of affective information on attitude change and impression formation. In addition, a great deal of work in more clinically oriented domains has been devoted to the influence of valenced or personally relevant
information on attention allocation. These two fields of research, which bear directly upon the role played by low level, automatic modes of processing in emotion
elicitation, will be reviewed here.
1.3.1. Affective priming
Zajonc (1980, 1984) bases his arguments for two separate “systems” in emotion elicitation on research showing that preferences are generated for stimuli which cannot be consciously perceived (e.g. Kunst-Wilson & Zajonc, 1980; Murphy &
Zajonc, 1993). His “affective primacy hypothesis”, claiming in particular that
affective reactions towards a stimulus can be elicited with minimal stimulus input and
virtually no cognitive processing, has since triggered much research in the domain of implicit perception and emotion (e.g. Niedenthal, 1990; Niedenthal & Kitayama, 1994; Isen & Diamond, 1989). For instance, Murphy and Zajonc (1993) carried out an experiment in which they established positive and negative valence for a previously neutral stimulus using an affective priming procedure. They compared the effects of what they called “affective” and “cognitive” priming on the judgement of previously neutral, novel targets (Chinese ideographs), under both extremely brief (4 msec) and longer exposure duration (1000 msec) of the primes. Pictures of faces expressing happiness and anger were used as affective primes, while small or large circles and squares, and symmetric and asymmetric objects were used as cognitive primes. They found that the affective primes presented at a suboptimal level, but not those
presented at a optimal level, produced significant shifts in subjects' evaluations of
“good” versus “bad” towards the targets. In contrast, cognitive primes only affected judgements concerning the possible meaning of the ideographs as representing a small or large object or being symmetric or asymmetric in the optimal presentation
condition.
These results were explained by claiming that “when affect is elicited at levels outside of conscious awareness, it is diffuse and its origin and address are unspecified.
Because of its diffuse quality, nonconscious affect can “spill over” onto unrelated stimuli” (p. 736). When presented at an optimal level of perception, hence when the source of affect is known, the affective reaction is, according to Murphy and Zajonc, less likely to be transferred to unrelated stimuli. Non-affective primes showed the opposite pattern according to the authors, due to this type of information needing a different degree of access to awareness (but see e.g. Lewicki, 1985, for effects of subliminal exposure of stimuli such as adjective-noun pairs onto judgements of
“better fitting” words in subsequent question-answer sessions, or Marcel, 1983, where both supraliminally and subliminally presented word primes almost equally affected lexical decision tasks). Researchers studying the mechanisms of evaluative
conditioning have proposed similar mechanisms of affect transfer, and have provided some empirical evidence that the transfer of affect from one stimulus onto a
contingently presented neutral stimulus can take place outside of awareness of the contingency (e.g. Baeyens, Eelen, & van den Bergh, 1990).
Automatic, unintentional effects of an affective nature were also observed in Bargh, Chaiken, Raymond, & Hymes (1996) in a series of studies aimed to replicate and extend findings of Fazio, Sanbonmatsu, Powell, and Kardes (1986). Bargh et al. found that the pronunciation of positively or negatively tainted target words was facilitated when these words were primed with other positive or negative words, without the words sharing any semantic features. These effects occurred even for mildly affective stimuli, such as “dentist”. The results suggest an automatic activation of the concepts
“good” and “bad” which cannot be explained by models of spreading semantic association (e.g. Neely, 1977) as the words used in the studies differed semantically.
In line with Zajonc’s affective primacy hypothesis, stronger effects were found when efforts were made to distract the participant from consciously evaluating words, compared with explicitly instructing the participants to evaluate words.
De Houwer and Eelen (1998) found further evidence of automatic valence processing.
In their experiments, subjects engaged in decision tasks where a target word was either a noun or an adjective. The response was given by saying aloud “positive” in response to a noun, or “negative” in response to an adjective as fast as possible. The target words were either positive, negative or neutral in valence, but subjects were instructed (in study 2 and 3) to ignore the affective connotations of the target words.
They consistently showed longer reaction times to words affectively discrepant with the connotation of their response than to words affectively congruent with the connotation of their response. Thus, even though the participants were explicitly instructed to ignore the affective connotations of the words which were irrelevant to performing the task well, the connotations were automatically activated, interfering with the task at hand.
In summary, using a variety of paradigms, the affective priming literature suggests that evaluations of stimuli in terms of their valence can take place automatically, even without awareness. These evaluations influence further processing by interference in the case of lexical decisions when the affective primes are discrepant, or by priming the evaluations of subsequently presented neutral stimuli in the sense of the affective valence of the prime. Furthermore, some evidence is obtained for affective priming being most effective when the source of the elicited affect is not explicitly recognised by the subject.
1.3.2. Attention allocation through automatic relevance evaluations
Recently, clinical research on emotion and attention incorporates information-processing models to address the role of emotional states and traits in attentional processes (selection and intensive processing of stimuli, see e.g. Wells & Matthews, 1994) and sustaining emotional thoughts (e.g. Teasdale & Barnard, 1993).
Experimental research in the field of attentional bias as a result of an emotional disturbance has been inspired by paradigms developed within cognitive psychology (e.g. the Stroop colour naming task; Stroop, 1935), resulting in interesting adaptations of these paradigms to research on affective disorders (e.g. using an emotion version of the Stroop task). This extensive body of work cannot be reviewed here; for more complete reviews of theoretical models and research results, the reader is referred to Teasdale & Barnard (1993), Wells & Matthews (1994) and Williams, Mathews, &
MacLeod (1996).
In brief, evidence so far shows that emotionally disturbed patients often show an attentional bias towards information relevant to their concerns or worries.
Furthermore, such concern-relevant information elicits a comparable attentional bias (although the effect is small in magnitude) when the information is presented
subliminally,. This research emphasises the automatic nature of the detection of relevance (see MacLeod & Hagan, 1992; Mogg, Bradley et al., 1993; Mogg, Kentish et al., 1993; all in Williams et al., 1996). Automatic, low-level processes, triggered by specific stimulus inputs and often interacting with higher-order controlled processes, are held responsible for this shift of attention toward potentially relevant information (e.g. Wells & Matthews, 1994).
An attentional bias effect has also been found in non-clinical groups with high trait emotion (e.g. trait-anxiety), or for normal participants following emotion induction, but the bias effects tend to be less pronounced and less reliable than in clinical
patients (Wells & Matthews, 1994). The fact that attentional bias is consistently found for persons high on certain emotional traits (especially trait anxiety) but hardly for normal individuals experiencing a particular emotional state (such as state anxiety), is explained by Wells and Matthews in terms of unusual and extensive
stimulus-response learning experiences, which are supposedly anchored in low-level memory traces. Whether or not most trait-anxious or phobics (i.e. those who are anxious with respect to particular objects) have actually encountered the object of their phobia in a more striking manner than nonphobics is an open question (see Rachman, 1974).
In summary, the research in the domain of social cognition has demonstrated that affective stimuli evaluated in an automatic manner, without elaborate cognitive, conscious processing, have an effect on subsequent (affective) processing. The studies on the emotional Stroop suggest that stimuli are automatically evaluated in terms of their relevance to personal concerns, and that the more a stimulus is relevant, the more attention is automatically captured by the stimulus and the harder this
attention-allocation is to overcome. Taken together, the research performed in these disciplines indicates that low-level, automatic evaluations might influence, or disrupt, higher level processing. This research, however, often concerns affect or preferences rather than emotions as such, and does not address how such general, global affect is important to, or develops into, emotions. Further specification is warranted of the mechanisms underlying the extraction of significant information and how this information influences further evaluations and emotional responses.
1.4. Multilevel models integrating both processing modes in emotion elicitation