Mapping the origins of time: Scalar errors in infant time estimation

Time is central to any understanding of the world. In adults, estimation errors grow linearly with the length of the interval, much faster than would be expected of a clock-like mechanism. Here we present the first direct demonstration that this is also true in human infants. Using an eye-tracking paradigm, we examined 4-, 6-, 10-, and 14-month-olds' responses to the omission of a recurring target, on either a 3- or 5-s cycle. At all ages (a) both fixation and pupil dilation measures were time locked to the periodicity of the test interval, and (b) estimation errors grew linearly with the length of the interval, suggesting that trademark interval timing is in place from 4 months

Help Yourself

Yet another novel about comedy, fame and madness. But with answers to the meaning of life thrown in for free. John Smith just died as a comedian but may have been reborn as a prophet of the present moment. Dr Hazel Cole has written a self-help book so good that it might even work on daytime TV presenters. Behind the scenes, billionaire press baron Eric Hayle seems to be pressing all the buttons. But will this mysterious man spoil everything? God only knows. And what happens if you ask 644 professional philosophers about the meaning of life, the universe and everything? Caspar knows because he tried it. The results are included in this edition at no extra cost to you. But knowledge comes at a price. You will have to put up with some of Caspar's ranting at the universe. This novel is published under a Creative Commons 3.0 CC-BY-SA licence. In other words... Help Yourself! Free Kindle and EBook versions available at the book URL

Unifying prospective and retrospective interval-time estimation: a fading-gaussian activation-based model of interval-timing

Hass and Hermann (2012) have shown that only variance-based processes will lead to the scalar growth of error that is characteristic of human time judgments. Secondly, a major meta-review of over one hundred studies (Block et al., 2010) reveals a striking interaction between the way in which temporal judgments are queried and cognitive load on participants’ judgments of interval duration. For retrospective time judgments, estimates under high cognitive load are longer than under low cognitive load. For prospective judgments, the reverse pattern holds, with increased cognitive load leading to shorter estimates. We describe GAMIT, a Gaussian spreading-activation model, in which the sampling rate of an activation trace is differentially affected by cognitive load. The model unifies prospective and retrospective time estimation, normally considered separately, by relating them to the same underlying process. The scalar property of time estimation arises naturally from the model dynamics and the model shows the appropriate interaction between mode of query and cognitive load

Embodiment and the origin of interval timing: kinematic and electromyographic data

Recent evidence suggests that interval timing (the judgment of durations lasting from approximately 500 ms. to a few minutes) is closely coupled to the action control system. We used surface electromyography (EMG) and motion capture technology to explore the emergence of this coupling in 4-, 6-, and 8-month-olds. We engaged infants in an active and socially relevant arm-raising task with 7 cycles and response period. In one condition cycles were slow (every 4 seconds) in another they were fast (every 2 seconds). In the slow condition, we found evidence of time locked sub-threshold EMG activity even in the absence of any observed overt motor responses at all 3 ages. This study shows that EMGs can be a more sensitive measure of interval timing in early development than overt behavior

Embodiment and the origin of interval timing: kinematic and electromyographic data

Recent evidence suggests that interval timing (the judgment of durations lasting from approximately 500 ms. to a few minutes) is closely coupled to the action control system. We used surface electromyography (EMG) and motion capture technology to explore the emergence of this coupling in 4-, 6-, and 8-month-olds. We engaged infants in an active and socially relevant arm-raising task with seven cycles and response period. In one condition, cycles were slow (every 4 s); in another, they were fast (every 2 s). In the slow condition, we found evidence of time-locked sub-threshold EMG activity even in the absence of any observed overt motor responses at all three ages. This study shows that EMGs can be a more sensitive measure of interval timing in early development than overt behavior

Motor activity improves temporal expectancy

Certain brain areas involved in interval timing are also important in motor activity. This raises the possibility that motor activity might influence interval timing. To test this hypothesis, we assessed interval timing in healthy adults following different types of training. The pre- and post-training tasks consisted of a button press in response to the presentation of a rhythmic visual stimulus. Alterations in temporal expectancy were evaluated by measuring response times. Training consisted of responding to the visual presentation of regularly appearing stimuli by either: (1) pointing with a whole-body movement, (2) pointing only with the arm, (3) imagining pointing with a whole-body movement, (4) simply watching the stimulus presentation, (5) pointing with a whole-body movement in response to a target that appeared at irregular intervals (6) reading a newspaper. Participants performing a motor activity in response to the regular target showed significant improvements in judgment times compared to individuals with no associated motor activity. Individuals who only imagined pointing with a whole-body movement also showed significant improvements. No improvements were observed in the group that trained with a motor response to an irregular stimulus, hence eliminating the explanation that the improved temporal expectations of the other motor training groups was purely due to an improved motor capacity to press the response button. All groups performed a secondary task equally well, hence indicating that our results could not simply be attributed to differences in attention between the groups. Our results show that motor activity, even when it does not play a causal or corrective role, can lead to improved interval timing judgments

The Laughing Baby: The Extraordinary Science behind what makes babies happy

Few things in life are more delightful than sharing in the laughter of a baby. Until now, however, psychologists and parenting experts have largely focused on moments of stress and confusion. Developmental psychologist Caspar Addyman decided to change that. Since 2012 Caspar has run the Baby Laughter project, collecting data, videos and stories from parents all over the world. This has provided a fascinating window into what babies are learning and how they develop cognitively and emotionally. Deeper than that, he has observed laughter as the purest form of human connection. It creates a bond that parents and infants share as they navigate the challenges of childhood. Moving chronologically through the first two years of life, The Laughing Baby explores the origin story for our incredible abilities. In the playful daily lives of babies, we find the beginnings of art, science, music and happiness. Our infancy is central to what makes us human, and understanding why babies laugh is key to understanding ourselves

Local redundancy governs infants' spontaneous orienting to visual-temporal sequences

Two experiments demonstrate that 5-month-olds are sensitive to local redundancy in visual-temporal sequences. In Experiment 1, 20 infants saw 2 separate sequences of looming colored shapes that possessed the same elements but contrasting transitional probabilities. One sequence was random whereas the other was based on bigrams. Without any prior exposure, infants looked longer at the random sequence. In Experiment 2, 17 infants looked equally long at bigram- and trigram-based sequences. However, an analysis of local redundancy revealed that in both experiments disengagement from the sequences was governed by local repetitions rather than by global sequence statistics. This finding suggests that a spontaneous sensitivity to stimulus complexity helps orient infants to sequences they can learn from

Rules and Similarity in the Development of Category Learning in Children and Infants

<p><strong>Abstract</strong></p> <p>Most theorists agree that adults can learn and use categories that are both rule- and similarity-based. There is less agreement about the mechanisms involved or on the distinction between rules and similarity. We begin by reviewing two recent theoretical positions, that of Pothos (2005) and of Ashby & colleagues (Ashby et al., 1998; Ashby and O’Brien, 2005). Identifying the notion of a rule to be the most problematic concept, we continue with a broader survey of rules in cognition.</p> <p>We propose that a developmental perspective could provide insight into these prob- lems. We review the existing literature from infancy and early childhood to show that previous studies have only tangentially investigated rules and similarity. We adapt and extend existing methods and present novel procedures and analyses that allow us to focus on a range of questions; When do rules emerge? What form do early rules take? Can statistical mechanisms give rise to rule-like performance? Is there a competition between rule and similarity processes?</p> <p>Four groups of experiments explore these questions. One set of experiments looks at 5-month-olds’ (and adults’) performance on several artificial grammar tasks devel- oped from Kirkham et al. (2002). We demonstrate that participants are sensitive to the complexity of certain sequence structures. Another pair of tasks investigate infants’ learning of abstract Same-Different relations. We find that 8-month-olds will learn the relation in both an habituation and an anticipation task, whereas 4-month-olds only succeed on the latter. A third group of tasks juxtapose unidi- mensional and family resemblance categorization using both rich and impoverished stimuli. We find that infants form flexible classifications. Finally, we present a set of computer games for young children that explore these questions in a more ecologically valid setting than traditional laboratory classification tasks.</p

Assessing Sensorimotor Synchronisation in Toddlers Using the Lookit Online Experiment Platform and Automated Movement Extraction.

Adapting gross motor movement to match the tempo of auditory rhythmic stimulation (sensorimotor synchronisation; SMS) is a complex skill with a long developmental trajectory. Drumming tasks have previously been employed with infants and young children to measure the emergence of rhythmic entrainment, and may provide a tool for identification of those with atypical rhythm perception and production. Here we describe a new protocol for measuring infant rhythmic movement that can be employed at scale. In the current study, 50 two-year-olds drummed along with the audiovisual presentation of four steady rhythms, using videos of isochronous drumming at 400, 500, 600, and 700 ms IOI, and provided their spontaneous motor tempo (SMT) by drumming in silence. Toddlers' drumming is observed from video recordings made in participants' own homes, obtained via the Lookit platform for online infant studies. We use OpenPose deep-learning model to generate wireframe estimates of hand and body location for each video. The vertical displacement of the hand was extracted, and the power and frequency of infants' rhythmic entrainment quantified using Fast Fourier Transforms. We find evidence for age-appropriate tempo-flexibility in our sample. Our results demonstrate the feasibility of a fully digital approach to measuring rhythmic entrainment from within the participant's home, from early in development