Target Cue Research Articles

Cognitive control of response inhibition and switching: Hemispheric lateralization and hand preference

Changing environmental constraints often make already prepared responses unnecessary or inappropriate. Under such circumstances, cognitive control enables to suppress the response or switch to alternative behavior. Here, we examine the neural dynamics of both functions in left- and right-handers who performed two variants of a paradigm that required either inhibition of the response or switching the response between hands. The EEG coherence data showed strengthening of interregional coupling in the alpha band (8–12Hz) following the target cues with an essential contribution of fronto-medial circuitry and a specific involvement of parietal areas in response switching. Brain-behavioral correlations revealed the functional significance of left-sided regions for successful response inhibition and switching, underlining the significant role of the left hemisphere for the organization of goal-directed activities. This lateralization pattern was observed for both left- and right-handers and suggests dominance of higher-order aspects of action planning in the left hemisphere.

The Effect of Implementation Intentions on Reactions to Nonspecified Situational Cues

The facilitative effect of implementation intentions on goal attainment has been demonstrated in past research (Gollwitzer & Sheeran, 2006). However, relatively little attention has been paid to the potential side effects of implementation intentions on the responses to nonspecified cues (i.e., cues not specified in implementation intentions). In the current study we investigated whether or not cue ambiguity would moderate the effect of implementation intentions on reactions to nonspecified cues. The results indicated reactions of our participants (42 undergraduate psychology students) to nonspecified cues were facilitated by implementation intentions, even when there was high ambiguity between the target and nonspecified cues. These results help clarify the underlying mechanisms of the effects of forming implementation intentions.

Categorical Vowel Perception Enhances the Effectiveness and Generalization of Auditory Feedback in Human-Machine-Interfaces

Human-machine interface (HMI) designs offer the possibility of improving quality of life for patient populations as well as augmenting normal user function. Despite pragmatic benefits, utilizing auditory feedback for HMI control remains underutilized, in part due to observed limitations in effectiveness. The goal of this study was to determine the extent to which categorical speech perception could be used to improve an auditory HMI. Using surface electromyography, 24 healthy speakers of American English participated in 4 sessions to learn to control an HMI using auditory feedback (provided via vowel synthesis). Participants trained on 3 targets in sessions 1–3 and were tested on 3 novel targets in session 4. An “established categories with text cues” group of eight participants were trained and tested on auditory targets corresponding to standard American English vowels using auditory and text target cues. An “established categories without text cues” group of eight participants were trained and tested on the same targets using only auditory cuing of target vowel identity. A “new categories” group of eight participants were trained and tested on targets that corresponded to vowel-like sounds not part of American English. Analyses of user performance revealed significant effects of session and group (established categories groups and the new categories group), and a trend for an interaction between session and group. Results suggest that auditory feedback can be effectively used for HMI operation when paired with established categorical (native vowel) targets with an unambiguous cue.

Eliminating the mere exposure effect through changes in context between exposure and test

The present study examined the extent to which increased liking of exposed stimuli—the mere exposure effect—is dependent on experiencing the stimuli in the same context in exposure and on test. Participants were repeatedly exposed to pairs of cues (nonsense words) and target stimuli (faces and shapes), and were asked to rate the pleasantness of the target stimuli in a subsequent test phase. Familiar targets were preferred to novel targets—a mere exposure effect was obtained. This preference for familiar targets was disrupted, however, when the cue–target pairings were rearranged between exposure and test, or a novel cue was introduced at test. Overall, the study suggests that the context of exposure and test moderates the mere exposure effect. Liking of stimuli due to exposure is specific to the context of exposure and does not apply to new or familiar but different contexts.

The effects of cue-specific inhibition training on alcohol consumption in heavy social drinkers.

Training social drinkers to exercise motor inhibitory control leads to a reduction in alcohol consumption. However, it is unclear if participants should attempt to exercise inhibitory control in the presence of alcohol-related cues or if nonspecific inhibition training is equally effective. It is also unclear if comparable effects can be demonstrated by training oculomotor inhibitory control. We trained motor inhibition in the context of a modified stop-signal task (experiment 1) and oculomotor inhibition in the context of a modified antisaccade task (experiment 2) before investigating the influence of these manipulations on alcohol consumption. Results from experiment 1 demonstrated that training motor inhibition in the presence of alcohol-related cues led to reduced ad libitum alcohol consumption in the laboratory but not self-reported drinking in the week after training. These effects were seen in contrast to a control group that received no inhibition training and another control group that was trained to inhibit only in the presence of neutral cues; alcohol consumption did not differ between the latter two groups. In experiment 2, training of oculomotor inhibition in the presence of alcohol-related cues led to slowed eye movements toward target cues on catch trials, but it did not influence the proportion of inhibitory failures and had no influence on alcohol consumption in the laboratory. We conclude that training participants to exercise inhibitory control in the presence of alcohol-related cues can reduce alcohol consumption, but the effects are transient and are only seen when motor, but not oculomotor, inhibition is trained.

Electrophysiological Correlates of Competitor Activation Predict Retrieval-Induced Forgetting

The very act of retrieval modifies the accessibility of memory for knowledge and past events and can also cause forgetting. A prominent theory of such retrieval-induced forgetting (RIF) holds that retrieval recruits inhibition to overcome interference from competing memories, rendering these memories inaccessible. The present study tested a fundamental tenet of the inhibitory-control account: The competition-dependence assumption. Event-related potentials (ERPs) were recorded while participants engaged in a competitive retrieval task. Competition levels were manipulated within the retrieval task by varying the cue-item associative strength of competing items. In order to temporally separate ERP correlates of competitor activation and target retrieval, memory was probed with the sequential presentation of 2 cues: A category cue, to reactivate competitors, and a target cue. As predicted by the inhibitory-control account, competitors with strong compared with weak cue-competitor association were more susceptible to forgetting. Furthermore, competition-sensitive ERP modulations, elicited by the category cue, were observed over anterior regions and reflected individual differences in ensuing forgetting. The present study demonstrates ERP correlates of the reactivation of tightly bound associated memories (the competitors) and provides support for the inhibitory-control account of RIF.

Strengthening encoding via implementation intention formation increases prospective memory commission errors

Prospective memory refers to the ability to remember to execute future intentions (e.g., taking medication with dinner). Although most prior research on prospective memory errors has focused on omission errors (i.e., failures to perform an intention in response to a target cue), there has been a recent surge in research on commission errors, the erroneous performance of a finished intention. Existing studies have examined factors at retrieval that lead to commission errors; the present study extends this research by investigating the impact of encoding strength. We found that relative to standard encoding, implementation intention encoding doubled the risk of commission errors in our laboratory paradigm for both young and older adults. This novel finding demonstrates the impact of encoding strength on commission errors and documents the potential challenges of deactivating the effects of implementation intentions upon completion of a prospective memory task.

Pain increases motivational drive to obtain reward, but does not affect associated hedonic responses: A behavioural study in healthy volunteers

Pain and reward have been suggested to interact, and some evidence is provided by a rodent study showing that acutely injured animals are more motivated to reach a food reward while they do not increase food consumption, pointing at unaltered reward liking. Since no data exist in humans, we conducted a psychophysical experiment to test the effects of experimentally induced tonic pain on (1) the motivation to receive reward and (2) hedonic responses when being rewarded. Forty healthy participants underwent two experimental sessions: in one, painful heat stimulation was continuously applied while participants played a monetary reward task; in the other, participants experienced non-painful warm stimulation while playing the task. In the task, participants needed to react quickly enough to a target cue to win the money associated with the particular trial ($0.04, $1 or $4). Reaction time to the target cue served as measure of motivation. Ratings after each trial on how much the participant liked the trial's outcome served as a measure of hedonic responses. Pain increased the motivation to obtain reward when the incentive was high, indexed by decreased reaction times (repeated-measures analysis of variance, interaction pain × incentive; p = 0.009). In contrast to motivational drive, hedonic ratings of the rewarding stimuli were not influenced by pain. Similar to existing rodent data, our results suggest a pain-induced mismatch of increased motivational drive with a lack of increased hedonic responses. This mismatch is discussed as perhaps reflecting a failed coping attempt, which is potentially relevant for chronic pain patients.

A role of the human thalamus in predicting the perceptual consequences of eye movements

Internal monitoring of oculomotor commands may help to anticipate and keep track of changes in perceptual input imposed by our eye movements. Neurophysiological studies in non-human primates identified corollary discharge (CD) signals of oculomotor commands that are conveyed via thalamus to frontal cortices. We tested whether disruption of these monitoring pathways on the thalamic level impairs the perceptual matching of visual input before and after an eye movement in human subjects. Fourteen patients with focal thalamic stroke and 20 healthy control subjects performed a task requiring a perceptual judgment across eye movements. Subjects reported the apparent displacement of a target cue that jumped unpredictably in sync with a saccadic eye movement. In a critical condition of this task, six patients exhibited clearly asymmetric perceptual performance for rightward vs. leftward saccade direction. Furthermore, perceptual judgments in seven patients systematically depended on oculomotor targeting errors, with self-generated targeting errors erroneously attributed to external stimulus jumps. Voxel-based lesion-symptom mapping identified an area in right central thalamus as critical for the perceptual matching of visual space across eye movements. Our findings suggest that trans-thalamic CD transmission decisively contributes to a correct prediction of the perceptual consequences of oculomotor actions.

Effects of varying target luminance and cue luminance on attentional effects of spatial cues

Attentional effects of letter cues on target processing were investigated in a bilateral spatial cueing paradigm. Luminance contrast of the cue stimuli and of the target stimuli were both manipulated. Consistent with predictions derived from theoretical models of visual attention, manipulating cue luminance and target luminance had very different effects on performance. In agreement with the dorsal stream attention hypothesis (Marrett et al., 2011) orienting effects were unaffected by changes in cue luminance; but in agreement with the work of Reynolds, Pasternak, and Desimone (2000) and Carrasco, Ling, and Read (2004) orienting effects were strongly modulated by changes in the luminance and perceptual quality of the target. Theoretical implications of the results are considered and the data are explained in terms of a sensory enhancement effect, whereby attention amplifies the neuronal responses for attended stimuli.

The effects of marker-related temporal cues on auditory gap-duration discrimination

In three experiments, we examined the ability of listeners to discriminate the duration of temporal gaps (silent intervals) and the influence of other temporal stimulus properties on their performance. In the first experiment, gap-duration discrimination thresholds were measured either in continuous noise or with noise markers with durations of 3 and 300 ms. Thresholds measured with 300-ms markers differed from those measured in continuous noise or with 3-ms markers. In the second experiment, stimuli consisting of a gap between two discrete markers were generated such that the gap duration, the onset-to-onset duration between markers, and the duration of the first marker were pseudorandomized across trials. Listeners' responses generally were consistent with the cue that was identified as the target cue from among the three cues in each block of trials, but the data suggested that the onset-to-onset cue was particularly salient in all conditions. Using a modified method-of-adjustment procedure in the third experiment, subjects were instructed to discriminate between the durations of gaps in discrete markers of different durations in two intervals, where the gap duration in one interval was adapted to measure the point of subjective equality. Without feedback, listeners tended to equate the onset-to-onset times of the markers rather than the gap durations. Overall, the results indicated that listeners' judgments of silent gaps between two discrete markers are strongly influenced by the onset-to-onset time, or rhythm, of the markers.

Subconscious Visual Cues during Movement Execution Allow Correct Online Choice Reactions

Part of the sensory information is processed by our central nervous system without conscious perception. Subconscious processing has been shown to be capable of triggering motor reactions. In the present study, we asked the question whether visual information, which is not consciously perceived, could influence decision-making in a choice reaction task. Ten healthy subjects (28±5 years) executed two different experimental protocols. In the Motor reaction protocol, a visual target cue was shown on a computer screen. Depending on the displayed cue, subjects had to either complete a reaching movement (go-condition) or had to abort the movement (stop-condition). The cue was presented with different display durations (20–160 ms). In the second Verbalization protocol, subjects verbalized what they experienced on the screen. Again, the cue was presented with different display durations. This second protocol tested for conscious perception of the visual cue. The results of this study show that subjects achieved significantly more correct responses in the Motor reaction protocol than in the Verbalization protocol. This difference was only observed at the very short display durations of the visual cue. Since correct responses in the Verbalization protocol required conscious perception of the visual information, our findings imply that the subjects performed correct motor responses to visual cues, which they were not conscious about. It is therefore concluded that humans may reach decisions based on subconscious visual information in a choice reaction task.

Examining the Effects of Cue Valence and Attention Load on Prospective Memory

Previous research has shown that emotion can affect memory. The current study examines the influence of target cues’ valence on prospective memory performance under both nondivided and divided attention loads. We predict that positive and negative valence words will lead to better prospective memory performance than neutral words. Understanding exactly how target cue valence impacts prospective remembering is vital in the future research and design of memory aids.

Conditioned suppression is an inverted-U function of footshock intensity

Most theories of associative learning assert that conditioned responding to a target cue is a monotonically increasing function of unconditioned-stimulus (US) intensity. In a lick suppression preparation with rats, a cue was paired with a 0.4-, 0.6-, 0.8-, 1.0-, 1.2-, or 1.4-mA footshock in Experiment 1a, and with a 0.3-, 0.8-, 1.3-, or 1.8-mA footshock in Experiment 1b. Subsequent suppression in response to the cue was an inverted-U function of the US intensity. In Experiment 2, we demonstrated that massive extinction of the training context and compound conditioning can each attenuate the response decrement caused by training with a high-intensity US. The sometimes-competing-retrieval model (Stout & Miller, Psychological Review 114:759-783, 2007) provides a better fit to these data than do several other models of associative learning.

Implementation-intention encoding in a prospective memory task enhances spontaneous retrieval of intentions

Although forming implementation intentions (Gollwitzer, 1999) has been demonstrated to generally improve prospective memory, the underlying cognitive mechanisms are not completely understood. It has been proposed that implementation-intention encoding encourages spontaneous retrieval (McDaniel & Scullin, 2010). Alternatively one could assume the positive effect of implementation-intention encoding is caused by increased or more efficient monitoring for target cues. To test these alternative explanations and to further investigate the cognitive mechanisms underlying implementation-intention benefits, in two experiments participants formed the intention to respond to specific target cues in a lexical decision task with a special key, but then had to suspend this intention during an intervening word-categorisation task. Response times on trials directly following the occurrence of target cues in the intervening task were significantly slower with implementation-intention encoding than with standard encoding, indicating that spontaneous retrieval was increased (Experiment 1). However, when activation of the target cues was controlled for, similar slowing was found with both standard and implementation-intention encoding (Experiment 2). The results imply that implementation-intention encoding as well as increased target–cue activation foster spontaneous retrieval processes.

Biological motion as a cue for spatial attention: Walking

Introduction: Movements of living entities in our environment are an important source of information. Here we explored walking movements as a cue for attention. A recent study reported a point-light walker (PLW) could induce reflexive attentional orienting in the direction it is facing, even when it is task irrelevant (Shi, et al., 2010). Given direction information from PLWs can be extracted without motion (Lange & Lappe, 2006) or from local motion alone (Troje & Westhoff, 2006), we wondered whether the attentional orienting effect was driven by form- or by motion-based processes. Methods: Subjects viewed PLWs that faced left or right that could also walk forward or backward (i.e., PL moonwalkers). A gabor patch was then presented either on the left or the right side of the screen. In Experiment 1, all PLWs were presented centrally and were task irrelevant. In Experiment 2, we presented occasional scrambled "catch" trials requiring subjects to attend the PLWs (even though they still did not cue target locations). We also presented the PLW cues both centrally and peripherally. Results: Experiment 1 failed to replicate Shi et al (2010): There was no evidence of attentional orienting in our data, neither for facing, nor for walking direction. In Experiment 2, where subjects had to attend the PLWs for an unrelated task, subjects were significantly more accurate in responding to targets congruent with the motion direction of the PLW. The effects were found only for central presentation of the PLWs. Conclusions: Reflexive attentional orienting effects induced by a PLW appear to be fickle. When subjects did not attend the PLW, there was no attentional effect. When subjects attended the PLW, we found a significant effect of motion direction, and not facing direction, and only when the PLW was presented centrally. Meeting abstract presented at VSS 2012

Averaging saccades are repelled by prior uninformative cues at both short and long intervals

When two spatially proximal stimuli are presented simultaneously, a first saccade is often directed to an intermediate location between the stimuli (averaging saccade). In an earlier study, Watanabe (2001) showed that, at a long cue–target onset asynchrony (CTOA; 600 ms), uninformative cues not only slowed saccadic response times (SRTs) to targets presented at the cued location in single target trials (inhibition of return, IOR), but also biased averaging saccades away from the cue in double target trials. The present study replicated Watanabe's experimental task with a short CTOA (50 ms), as well as with mixed short (50 ms) and long (600 ms) CTOAs. In all conditions on double target trials, uninformative cues robustly biased averaging saccades away from cued locations. Although SRTs on single target trials were delayed at previously cued locations at both CTOAs when they were mixed, this delay was not observed in the blocked, short CTOA condition. We suggest that top-down factors, such as expectation and attentional control settings, may have asymmetric effects on the temporal and spatial dynamics of oculomotor processing.

Context effects in evaluative conditioning of implicit evaluations

Propositional models of evaluative conditioning postulate that the impact of stimulus pairings on liking should depend not on the pairings themselves but on what the pairings imply about the relation between stimuli. Hence, context manipulations that change the implications of stimulus pairings should moderate evaluative conditioning. We manipulated context by varying the way in which context cues were paired with affective outcomes while keeping the pairings between target cues and affective outcomes constant. All participants saw one target cue compound that was followed by a positive outcome (XF+) and another target cue compound that was followed by a negative outcome (YG−). In condition Same, each context cue was consistently paired with a positive or negative outcome, regardless of whether it was presented alone or in compound with another cue (A+, B+, AB+; C−, D−, CD−). In condition Opposite, however, a context cue was paired with a certain outcome when presented alone and with an outcome of the opposite valence when presented in a compound with another cue (A+, B+, AB−; C−, D−, CD+). Employing several implicit measures, we assessed the implicit evaluations of the target cues X and Y. In all three studies, the outcome of the measurement procedure differed between conditions. In condition Same, the positively paired cue X was evaluated more positively than the negatively paired cue Y. In condition Opposite, however, this preference was not present. This pattern of results suggests that EC is determined not only by the objective pairings but also by the context in which these pairings occur. Implications for models of evaluative conditioning are discussed.

Attentional biases to foods: The effects of caloric content and cognitive restraint

The goal of the present study was to determine whether female restrained and unrestrained eaters demonstrated differential levels of attentional bias to high calorie foods when they were presented as distractors in a flanker task. This task consisted of four blocks of 68 trials in which three food pictures were briefly presented simultaneously on a computer screen. On each trial a high or low calorie target food was presented in the center of a pair of high or low calorie food flanker pictures and participants’ reaction times to answer a basic question about whether they would consume the target food for breakfast were recorded. In Experiment 1, in which all participants were fed a snack prior to engaging in the flanker task, there was no evidence that restrained (n=29) or unrestrained (n=37) eaters had an attentional bias. However, in Experiment 2, when participants completed the flanker task while hungry, restrained eaters (n=27) experienced response conflict only when low calorie targets were flanked by high calorie distractors, whereas unrestrained eaters (n=46) were distracted by high calorie flankers regardless of the caloric content of the target cue. The results from this implicit task indicate that flankers interfere with hungry participants’ responses to varying degrees depending on their cognitive restraint. Whether attentional bias to food cues subsequently affects food choices and eating behavior is a topic for further investigation.

Which cue to ‘want’? Opioid stimulation of central amygdala makes goal-trackers show stronger goal-tracking, just as sign-trackers show stronger sign-tracking

Pavlovian cues that have been paired with reward can gain incentive salience. Drug addicts find drug cues motivationally attractive and binge eaters are attracted by food cues. But the level of incentive salience elicited by a cue re-encounter still varies across time and brain states. In an animal model, cues become attractive and ‘wanted’ in an ‘autoshaping’ paradigm, where different targets of incentive salience emerge for different individuals. Some individuals (sign-trackers) find a predictive discrete cue attractive while others find a reward contiguous goal cue more attractive (location where reward arrives: goal-trackers). Here we assessed whether central amygdala mu opioid receptor stimulation enhances the phasic incentive salience of the goal-cue for goal-trackers during moments of predictive cue presence (expressed in both approach and consummatory behaviors to goal cue), just as it enhances the attractiveness of the predictive cue target for sign-trackers. Using detailed video analysis we measured the approaches, nibbles, sniffs, and bites directed at their preferred target for both sign-trackers and goal-trackers. We report that DAMGO microinjections in central amygdala made goal-trackers, like sign-trackers, show phasic increases in appetitive nibbles and sniffs directed at the goal-cue expressed selectively whenever the predictive cue was present. This indicates enhancement of incentive salience attributed by both goal trackers and sign-trackers, but attributed in different directions: each to their own target cue. For both phenotypes, amygdala opioid stimulation makes the individual's prepotent cue into a stronger motivational magnet at phasic moments triggered by a CS that predicts the reward UCS.