Temporal predictive mechanisms modulate motor reaction time during initiation and inhibition of speech and hand movement

Skilled movement is mediated by motor commands executed with extremely fine temporal precision. The question of how the brain incorporates temporal information to perform motor actions has remained unanswered. This study investigated the effect of stimulus temporal predictability on response timing of speech and hand movement. Subjects performed a randomized vowel vocalization or button press task in two counterbalanced blocks in response to temporally-predictable and unpredictable visual cues. Results indicated that speech and hand reaction time was decreased for predictable compared with unpredictable stimuli. This finding suggests that a temporal predictive code is established to capture temporal dynamics of sensory cues in order to produce faster movements in responses to predictable stimuli. In addition, results revealed a main effect of modality, indicating faster hand movement compared with speech. We suggest that this effect is accounted for by the inherent complexity of speech production compared with hand movement. Lastly, we found that movement inhibition was faster than initiation for both hand and speech, suggesting that movement initiation requires a longer processing time to coordinate activities across multiple regions in the brain. These findings provide new insights into the mechanisms of temporal information processing during initiation and inhibition of speech and hand movement.     

Manipulating cues in mind wandering: Verbal cues affect the frequency and the temporal focus of mind wandering

Our understanding of mind wandering (MW) has dramatically increased over the past decade. A key challenge still facing research is the identification of the processes and events that directly cause and control its occurrence. In the present study we sought to shed light on this question, by investigating the effects of verbal cues on the frequency and temporal focus of MW. To this aim, we experimentally manipulated the presence of irrelevant verbal cues during a vigilance task, in two independent groups (Verbal-cues group vs. No-cues group).We found that compared to the No-cues group, the Verbal-cues group reported a higher amount of MW, mostly triggered by the irrelevant cue-words, and a higher proportion of past-oriented MW compared to the other temporal orientations. These results demonstrate that task-irrelevant verbal stimulation increases the frequency of MW and steers its temporal orientation toward the past. Implications for the research on MW are discussed.     

The roles of the temporal lobe in creative insight: an integrated review

Recent studies have revealed that the temporal lobe, a cortical region thought to be in charge of episodic and semantic memory, is involved in creative insight. This work examines the contributions of discrete temporal regions to insight. Activity in the medial temporal regions is indicative of novelty recognition and detection, which is necessary for the formation of novel associations and the “Aha!” experience. The fusiform gyrus mainly affects the formation of gestalt-like representation and perspective taking. The anterior and posterior middle temporal gyri (MTG) are individually associated with extensive semantic processing and inhibiting salient or routine word associations, which are necessary to form non-salient, novel and remote associations. The anterior and posterior superior temporal gyri (STG) are individually responsible for integrating/binding and accessing various types of available conceptual representations. Based on the current knowledge, an integrated model of the temporal lobe's role in insight and some future directions are proposed.     

Intertrial pellets influence the acquisition and expression of timed appetitive responding in rats

Two experiments examined temporally based changes in the conditioned magazine-entries of rats when a target food pellet arrived at a fixed time before the termination of a conditioned stimulus. Both experiments found that increasing the rate of intertrial pellets systematically interfered with the rate of acquisition. When intertrial pellets were featured in acquisition, their omission on test trials also resulted in a very poorly expressed conditioned response. On test trials preceded by intertrial pellets, however, peak times in groups trained with intertrial pellets were shifted in a rightward direction under a long but not short interstimulus interval. This rightward shift was accompanied by a smaller standard deviation. Our key findings are best accommodated by real-time associative models.     

Sharing with others and delaying for the future in preschoolers

This study explored age differences in preschoolers’ temporal and social discounting and the association of these abilities. Research indicates that 4-year-olds are sensitive to rewards of differing magnitude (Lemmon & Moore, 2007). However, it is unclear whether preschoolers are able to consider length of time when making a choice to delay (Mischel, Masters, & Grusec, 1969). In this study, 66, 3- and 4-year-olds were presented a delay of gratification task in which length of delay was manipulated. Additionally, they were given a sharing task in which they distributed toys between themselves, a friend, and another peer. Results suggested sensitivity to delay differences only in the oldest group. Furthermore, delay sensitivity was associated with sharing more preferred toys with friends compared to another peer, suggesting that favoring the “self” closer in time overlaps with favoring “another” who is closer socially.     

Perception of intersensory synchrony in audiovisual speech: not that special

Perception of intersensory temporal order is particularly difficult for (continuous) audiovisual speech, as perceivers may find it difficult to notice substantial timing differences between speech sounds and lip movements. Here we tested whether this occurs because audiovisual speech is strongly paired (“unity assumption”). Participants made temporal order judgments (TOJ) and simultaneity judgments (SJ) about sine-wave speech (SWS) replicas of pseudowords and the corresponding video of the face. Listeners in speech and non-speech mode were equally sensitive judging audiovisual temporal order. Yet, using the McGurk effect, we could demonstrate that the sound was more likely integrated with lipread speech if heard as speech than non-speech. Judging temporal order in audiovisual speech is thus unaffected by whether the auditory and visual streams are paired. Conceivably, previously found differences between speech and non-speech stimuli are not due to the putative “special” nature of speech, but rather reflect low-level stimulus differences.     

The ecological rationality of delay tolerance: insights from capuchin monkeys

Both human and non-human animals often face decisions between options available at different times, and the capacity of delaying gratification has usually been considered one of the features distinguishing humans from other animals. However, this characteristic can widely vary across individuals, species, and types of task and it is still unclear whether it is accounted for by phylogenetic relatedness, feeding ecology, social structure, or metabolic rate. To disentangle these hypotheses, we evaluated temporal preferences in capuchin monkeys, South-American primates that, despite splitting off from human lineage approximately 35 million years ago, show striking behavioural analogies with the great apes. Then, we compared capuchins’ performance with that of the other primate species tested so far with the same procedure. Overall, capuchins showed a delay tolerance significantly higher than closely related species, such as marmosets and tamarins, and comparable to that shown by great apes. Capuchins’ tool use abilities might explain their comparatively high preference for delayed options in inter-temporal choices. Moreover, as in humans, capuchin females showed a greater delay tolerance than males, possibly because of their less opportunistic foraging style. Thus, our results shed light on the evolutionary origins of self-control supporting explanations of delay tolerance in terms of feeding ecology.     

Cognitive control of a simple mental image in patients with obsessive--compulsive disorder

The nature of obsessions has led researchers to try to determine if the main problem in obsessive-compulsive disorder (OCD) is impaired inhibitory control. Previous studies report that the effort to suppress is one of the factors that increase the frequency of obsessive thoughts. Based on these results and those of the present study that suggest inferior parietal lobe (IPL) abnormality in OCD and findings of a recent study that reported the importance of the right posterior parietal cortex in cognitive control of a simple mental image, the present cognitive control paradigm study aimed to determine whether there is a difference in brain dynamics between OCD patients and non-obsessive controls while performing tasks that necessitate cognitive control of a simple mental image, and whether the right posterior parietal region is one of the regions in which a difference in activity between the OCD patients and controls would be observed. Functional brain imaging was performed while the participants attempted to suppress, imagine, or manipulate a mental image. The general linear model showed that there was a main effect of group and main effect of task. Accordingly, in all contrasts (suppression minus free-imagination, erasing minus free-imagination, and imagination minus free-imagination), the right IPL, right posterior cingulate cortex, and right superior frontal gyrus activity were lower in the OCD patients than in the healthy controls. These results and the observed correlations between activity levels, and symptom and subjective performance scores are discussed. In conclusion, the results of the present study and those of previous studies suggest that the main problem in OCD might be difficulty activating the right frontoparietal networks during tasks that require cognitive control, which might result in the intrusiveness of obsessive thoughts.     

Temporal stability of the Francis Scale of Attitude toward Christianity: Test-retest data over five weeks

Recently Lewis, Cruise, and Mc Guckin (2005) have reported on the test-retest reliability of the 7-item version of the Francis Scale of Attitude toward Christianity; however, their study was limited. The present aim was to evaluate the temporal stability of both the 24- and 7-item versions of the Francis Scale of Attitude toward Christianity over a five-week period among a sample of 114 Irish undergraduate university students. Data demonstrated that stability across the two administrations was very high for both the 24- (r = .95) and 7-item (r = .94) versions. These data support the short-term test-retest reliability of both the 24- and 7-item versions of the Francis Scale of Attitude toward Christianity.     

Present and future temporal profiles and their relationship to health intentions and behaviors: A test on a Norwegian general population sample

We investigated the temporal profiles of a Norwegian general population sample and their relation to health behaviors and intentions. The profiles were based on variables from the present and future dimensions of the Zimbardo Time Perspective Inventory (ZTPI), the Consideration of Future Consequences Scale (CFCS), and the combination of both scales. The analysis revealed that there were only two stable clusters that corresponded to the present and the future profiles. Generally, CFCS‐based present and future profiles were more effective at predicting health behaviors and intentions than ZTPI‐based profiles. Profiles based on the CFCS variables were more predictive of eating behaviors. However, the profiles based on the combination of both CFCS and ZTPI were more predictive of smoking, exercising, and health intentions than the profiles based solely on the CFCS. The variation in walking was explained only by the profiles based on a combination of CFCS and ZTPI.