Adolescent-specific memory effects: Evidence from working memory, immediate and 24-hour recognition memory performance in 8- to 30-year-olds

Working memory and long-term memory develop from childhood to adulthood, but the relationship between them is not fully understood, especially during adolescence. We investigated associations between n-back task performance and subsequent recognition memory in a community sample (8-30 years, n=150) using tasks from the Adolescent Brain Cognitive Development Study (ABCD Study®). We added a 24-hour delay condition to assess long-term memory and assessed ages that overlap with those to be assessed in the 10-year ABCD study. Overall working memory, immediate, and long-term recognition memory performance peaked during adolescence. Age effects in recognition memory varied by items (i.e., old targets and distractors and new items) and delay. For immediate recognition, accuracy was higher for new items and targets than distractors, with the highest accuracy for new items emerging by the mid-teens. For long-term recognition, adolescents were more accurate in identifying new items than children and adults and adolescents showed more long-term forgetting of distractors relative to targets. In contrast, adults showed similar accuracy for targets and distractors, while children showed long-term forgetting of both. The results suggest that working memory processes may facilitate long-term storage of task-relevant items over irrelevant items and may benefit the detection of novel information during adolescence.

A Novel Method to Control Leakage and Noise in Domino Circuit for Wide Fan-in OR Logic

This paper proposes a novel method to control leakage and noise in domino circuits for wide fan-in OR logic with low power consumption, low process variation, and higher noise margin under the similar delay condition. In the proposed method, output and dynamic nodes are isolated from the PDN (Pull-Down Network) to improve the noise immunity and reduce switching activity. Further, with the aid of a transistor in the stack, the sub-threshold current is reduced. Thus, the proposed domino is applicable for high-speed and low-power applications in deep sub-micro-range. Simulation results show that the proposed domino improves the noise immunity and figure of merit (FOM) by factors of 1.95 and 2.34, respectively, with respect to the conventional domino with a footer. Along with this improvement, 26% reduction is also observed in power consumption. The entire simulations for all the domino circuits are done at 45-nm CMOS technology by using SPECTRE simulator under the Cadence Virtuoso environment.

D-OLIA: A Hybrid MPTCP Congestion Control Algorithm with Network Delay Estimation

With the recent evolution of mobile technology, modern devices equipped with multiple communication interfaces have become popular. The multipath transmission control protocol (MPTCP) has evolved to facilitate multiple communication interfaces through a single TCP connection for faster Internet access. MPTCP congestion control algorithms (MPTCP-CCAs) control data flow by fulfilling three design goals, i.e., ensuring improvement over single-path flows, ensuring fairness, and balancing congestion. Current MPTCP-CCAs cannot fulfill these design goals. For example, the opportunistic-linked increase algorithm (OLIA), a well-known MPTCP-CCA in load balancing, often results in low throughput because it cannot properly utilize the underlying network. In addition, the current Internet has a rapidly changing characteristic due to a large amount of short-lived traffic, making it difficult for MPTCP-CCAs to cope. An awareness of prevailing network delay conditions might help MPTCP-CCAs to utilize the network capacity fully. Therefore, we propose dynamic OLIA (D-OLIA), a hybrid MPTCP-CCA that enhances the performance of OLIA by integrating an awareness of the current network delay condition for deciding the congestion window (CWND) decrease factor. We estimate the current network delay condition, i.e., less-congested or congested, by observing the changes in the round-trip-time (RTT). Based on the estimated network delay condition, we decide the CWND decrease factor in real-time for reducing the CWND during packet loss events. We implemented D-OLIA in the Linux kernel and experimented using the Mininet emulator. The emulation results demonstrate that D-OLIA successfully estimates current network delay conditions and results in approximately a 20% increased throughput compared to the original OLIA. Compared to certain MPTCP-CCAs, it also yields a highly improved performance in terms of throughput, RTT, packet retransmissions, and fairness among the MPTCP sub-flows.

Midfrontal theta oscillation encodes haptic delay

Haptic technologies aim to simulate tactile or kinesthetic interactions with a physical or virtual environment in order to enhance user experience and/or performance. However, due to stringent communication and computational needs, the user experience is influenced by delayed haptic feedback. While delayed feedback is well understood in the visual and auditory modalities, little research has systematically examined the neural correlates associated with delayed haptic feedback. In this paper, we used electroencephalography (EEG) to study sensory and cognitive neural correlates caused by haptic delay during passive and active tasks performed using a haptic device and a computer screen. Results revealed that theta power oscillation was significantly higher at the midfrontal cortex under the presence of haptic delay. Sensory correlates represented by beta rebound were found to be similar in the passive task and different in the active task under the delayed and synchronous conditions. Additionally, the event related potential (ERP) P200 component is modulated under the haptic delay condition during the passive task. The P200 amplitude significantly reduced in the last 20% of trials during the passive task and in the absence of haptic delay. Results suggest that haptic delay could be associated with increased cognitive control processes including multi-sensory divided attention followed by conflict detection and resolution with an earlier detection during the active task. Additionally, haptic delay tends to generate greater perceptual attention that does not significantly decay across trials during the passive task.

Parieto-Occipital Alpha and Low-Beta EEG Power Reflect Sense of Agency

The sense of agency (SoA) is part of psychophysiological modules related to the self. Disturbed SoA is found in several clinical conditions, hence understanding the neural correlates of the SoA is useful for the diagnosis and determining the proper treatment strategies. Although there are several neuroimaging studies on SoA, it is desirable to translate the knowledge to more accessible and inexpensive EEG-based biomarkers for the sake of applicability. However, SoA has not been widely investigated using EEG. To address this issue, we designed an EEG experiment on healthy adults (n = 15) to determine the sensitivity of EEG on the SoA paradigm using hand movement with parametrically delayed visual feedback. We calculated the power spectral density over the traditional EEG frequency bands for ten delay conditions relative to no delay condition. Independent component analysis and equivalent current dipole modeling were applied to address artifact rejection, volume conduction, and source localization to determine the effect of interest. The results revealed that the alpha and low-beta EEG power increased in the parieto-occipital regions in proportion to the reduced SoA reported by the subjects. We conclude that the parieto-occipital alpha and low-beta EEG power reflect the sense of agency.

Young children share more under time pressure than after a delay

Adults under time pressure share with others generously, but with more time they act more selfishly. In the current study, we investigated whether young children already operate in this same way, and, if so, whether this changes over the preschool and early school age years. We tested 144 children in three age groups (3-, 5-, and 7-year olds) in a one-shot dictator game: Children were given nine stickers and had the possibility to share stickers with another child who was absent. Children in the Time Pressure condition were instructed to share quickly, whereas children in the Delay condition were instructed to take time and consider their decision carefully. Across ages, children in the Time Pressure condition shared significantly more stickers than children in the Delay condition. Moreover, the longer children waited, the less they shared. Thus, children, like adults, are more prosocial when acting spontaneously than after considering their decision more carefully.

EXPRESS: Distraction by auditory novelty during reading: Evidence for disruption in saccade planning, but not saccade execution

Novel or unexpected sounds that deviate from an otherwise repetitive sequence of the same sound cause behavioural distraction. Recent work has suggested that distraction also occurs during reading as fixation durations increased when a deviant sound was presented at the fixation onset of words. The present study tested the hypothesis that this increase in fixation durations occurs due to saccadic inhibition. This was done by manipulating the temporal onset of sounds relative to the fixation onset of words in the text. If novel sounds cause saccadic inhibition, they should be more distracting when presented during the second half of fixations when saccade programming usually takes place. Participants read single sentences and heard a 120 ms sound when they fixated five target words in the sentence. On most occasions (p= 0.9), the same sine wave tone was presented (“standard”), while on the remaining occasions (p= 0.1) a new sound was presented (“novel”). Critically, sounds were played either during the first half of the fixation (0 ms delay) or during the second half of the fixation (120 ms delay). Consistent with the saccadic inhibition hypothesis, novel sounds led to longer fixation durations in the 120 ms compared to the 0 ms delay condition. However, novel sounds did not generally influence the execution of the subsequent saccade. These results suggest that unexpected sounds have a rapid influence on saccade planning, but not saccade execution.

Time Perception and Depression Symptoms: A Perceived Delay Cues Feelings of Hopelessness

The relationship between time perception and affect is bidirectional: Negative affective states tend to dilate (i.e., expand or slow) perceived duration, and unexpected delays (i.e., expanded durations) can induce negative affect like boredom or frustration. However, when studying time perception in affective disorders like depression, the direction of effect is typically viewed in terms of how affect, emotion or mood distort time perception. This experimental study reverses the direction of effect by showing that an experimentally-induced and unexpected expansion of time (i.e., “delay” condition) can increase reported levels of hopelessness, a symptom of depression. After a brief time production task, non-depressed participants who had been randomly allocated longer second than first intervals (i.e., an experimentally cued “delay”) reported higher levels of subsequent hopelessness. This was especially true for their “feelings about the future”, a subscale of the Beck Hopelessness Scale. It is proposed that the “delay” effect occurred where feelings of frustration or boredom with short-term present experience were generalized to the long-term expected future. Increased hopelessness after an unexpected delay is thought to be the result of a change in hierarchical Bayesian inference. A change in lower-order statistical reasoning about the present timing task affected higher-order abstract reasoning about the future. This suggests a potentially modifiable link between time perception and a common symptom of depression.