Categorising: Inside the crow's brain.

Crows can learn to categorise line lengths into experimenter-defined categories. The crow's brain codes and recodes line lengths in individual neurons in the nidopallium caudolaterale, part of the telencephalon.

Digital games for learning basic arithmetic at home.

Many early learners need individualized support when regular teaching is not readily available. Here we present results of a progressive digital game that was played at home rather than under the supervision of the teacher. "NumberBeads" was designed to help low attaining learners, but also typical early learners. The game required learners to construct objects-sets and digits-to match a target object, and was played at home using an online platform. The participants were first-graders (n=140) enrolled in 10 classrooms randomly assigned to two groups. One group played NumberBeads, requiring students to construct solutions in a microworld of sets and digits. Another group played a similar game, NumberChoice, which contained the same elements, sets and digits, but used multiple-choice questions with right/wrong feedback. Results showed that learners using both games were able to complete the game unsupervised at home, but there was greater improvement with NumberBeads especially with learners identified as low attaining. Overall these findings support the feasibility of boosting early numeracy at home using a game designed to help basic numerical competence that requires no teacher supervision, and very little guidance by parents or carers.

Characterizing ontogeny of quantity discrimination in zebrafish.

A sense of non-symbolic numerical magnitudes is widespread in the animal kingdom and has been documented in adult zebrafish. Here, we investigated the ontogeny of this ability using a group size preference (GSP) task in juvenile zebrafish. Fish showed GSP from 21 days post-fertilization and reliably chose the larger group when presented with discriminations of between 1 versus 3, 2 versus 5 and 2 versus 3 conspecifics but not 2 versus 4 conspecifics. When the ratio between the number of conspecifics in each group was maintained at 1 : 2, fish could discriminate between 1 versus 2 individuals and 3 versus 6, but again, not when given a choice between 2 versus 4 individuals. These findings are in agreement with studies in other species, suggesting the systems involved in quantity representation do not operate separately from other cognitive mechanisms. Rather they suggest quantity processing in fishes may be the result of an interplay between attentional, cognitive and memory-related mechanisms as in humans and other animals. Our results emphasize the potential of the use of zebrafish to explore the genetic and neural processes underlying the ontogeny and function of number cognition.

Drivers of Decadal Carbon Fluxes Across Temperate Ecosystems.

Long-running eddy covariance flux towers provide insights into how the terrestrial carbon cycle operates over multiple timescales. Here, we evaluated variation in net ecosystem exchange (NEE) of carbon dioxide (CO2) across the Chequamegon Ecosystem-Atmosphere Study AmeriFlux core site cluster in the upper Great Lakes region of the USA from 1997 to 2020. The tower network included two mature hardwood forests with differing management regimes (US-WCr and US-Syv), two fen wetlands with varying levels of canopy sheltering and vegetation (US-Los and US-ALQ), and a very tall (400 m) landscape-level tower (US-PFa). Together, they provided over 70 site-years of observations. The 19-tower Chequamegon Heterogenous Ecosystem Energy-balance Study Enabled by a High-density Extensive Array of Detectors 2019 campaign centered around US-PFa provided additional information on the spatial variation of NEE. Decadal variability was present in all long-term sites, but cross-site coherence in interannual NEE in the earlier part of the record became weaker with time as non-climatic factors such as local disturbances likely dominated flux time series. Average decadal NEE at the tall tower transitioned from carbon source to sink to near neutral over 24 years. Respiration had a greater effect than photosynthesis on driving variations in NEE at all sites. Declining snowfall offset potential increases in assimilation from warmer springs, as less-insulated soils delayed start of spring green-up. Higher CO2 increased maximum net assimilation parameters but not total gross primary productivity. Stand-scale sites were larger net sinks than the landscape tower. Clustered, long-term carbon flux observations provide value for understanding the diverse links between carbon and climate and the challenges of upscaling these responses across space.

Numerical activities of daily living: a short version.

Specific impairments in numerical functions may cause severe problems in everyday life that cannot be inferred from the available scales evaluating instrumental activities of daily living. The Numerical Activities of Daily living (NADL) is a battery designed to assess the patient's performance in everyday activities involving numbers (Informal Test) and in more scholastic capacities (Formal Test). A downside of this battery is its duration (45 min). The aim of the present study is to build a shorter version of NADL to make it more suitable for clinical and research purposes. The shortening procedure involved only the Formal test, and followed two steps: (i) a correlation of subtests with the general scores, and (ii) an item-analysis within the subtests previously showing higher correlations. Correlations between NADL-Short and NADL original version, and the new cut-offs were calculated. Lastly, the relationship between NADL-Short and other brief cognitive screening tests used in the clinical practice was evaluated in neurological patients and healthy controls. The NADL-Short includes the original Informal Test and the shortened Formal Test. It is a quick and easy clinical tool (15 min) to assess numerical abilities applied to informal and formal situations. It correlates highly with the original battery (Kendall's tau greater than 0.6 across tasks) and the cut-offs correctly identify impaired performance (accuracy of 95% or above). Correlation analysis showed a low positive correlation between NADL-Short and other brief cognitive scales. These findings suggest that it is appropriate to use specific tools to make inferences about a person's numerical abilities.

Arithmetic learning modifies the functional connectivity of the fronto-parietal network.

How Resting-State Functional Connectivity (RSFC) is modified by learning is an important but rarely asked question. Here we used functional near-infrared spectroscopy (fNIRS) to measure changes in RSFC after learning novel subtraction and multiplication facts by forty-one young adult volunteers. We also measured changes in regional hemoglobin concentration. Fronto-parietal RSFC was modified by arithmetic learning and the fronto-parietal RSFC configuration before learning predicted the effectiveness of arithmetic learning. We also found a significant learning effect indicated by a monotonic decrease in reaction time and an increase in accuracy. Regional task-dependent oxy-hemoglobin concentration differentiated subtraction from multiplication learning supporting previous fMRI findings. These results suggest the sensitivity and importance of fronto-parietal connectivity to arithmetic learning.

Variability in Single Digit Addition Problem-Solving Speed Over Time Identifies Typical, Delay and Deficit Math Pathways.

We assessed the degree to which the variability in the time children took to solve single digit addition (SDA) problems longitudinally, predicted their ability to solve more complex mental addition problems. Beginning at 5 years, 164 children completed a 12-item SDA test on four occasions over 6 years. We also assessed their (1) digit span, visuospatial working memory, and non-verbal IQ, and (2) the speed with which they named single numbers and letters, as well the speed enumerating one to three dots as a measure of subitizing ability. Children completed a double-digit mental addition test at the end of the study. We conducted a latent profile analysis to determine if there were different SDA problem solving response time (PRT) variability patterns across the four test occasions, which yielded three distinct PRT variability patterns. In one pattern, labeled a typical acquisition pathway, mean PRTs were relatively low and PRT variability diminished over time. In a second pattern, label a delayed pathway, mean PRT and variability was high initially but diminished over time. In a third pattern, labeled a deficit pathway, mean PRT and variability remained relatively high throughout the study. We investigated the degree to which the three SDA PRT variability pathways were associated with (1) different cognitive ability measures, and (2) double-digit mental addition abilities. The deficit pathway differed from the typical and delayed pathway on the subitizing measure only, but not other measures; and the latter two pathways also differed from each other on the subitizing but not other measures. Double-digit mental addition problem solving success differed between each of the three pathways, and mean PRT variability differed between the typical and the delayed and deficit pathways. The latter two pathways did not differ from each other. The findings emphasize the value of examining individual differences in problem-solving PRT variability longitudinally as an index of math ability, and highlight the important of subitizing ability as a diagnostic index of math ability/difficulties.

Culture-Independent Prerequisites for Early Arithmetic.

In numerate societies, early arithmetic development is associated with visuospatial working memory, executive functions, nonverbal intelligence, and magnitude-comparison abilities. To what extent do these associations arise from cultural practices or general cognitive prerequisites? Here, we administered tests of these cognitive abilities (Corsi Blocks, Raven's Colored Progressive Matrices, Porteus Maze) to indigenous children in remote northern Australia, whose culture contains few counting words or counting practices, and to nonindigenous children from an Australian city. The indigenous children completed a standard nonverbal addition task; the nonindigenous children completed a comparable single-digit addition task. The correlation matrices among variables in the indigenous and nonindigenous children showed similar patterns of relationships, and parallel regression analyses showed that visuospatial working memory was the main predictor of addition performance in both groups. Our findings support the hypothesis that the same cognitive capacities promote competence for learners in both numerate and nonnumerate societies.

The implications for education of an innate numerosity-processing mechanism.

One specific cause of low numeracy is a deficit in a mechanism for representing and processing numerosities that humans inherited and which is putatively shared with many other species. This deficit is evident at each of the four levels of explanation in the 'causal modelling' framework of Morton and Frith (Morton and Frith 1995 In Manual of developmental psychopathology, vol. 1 (eds D Cichetti, D Cohen), pp. 357-390). Very low numeracy can occur in cognitively able individuals with normal access to good education: it is linked to an easily measured deficit in basic numerosity processing; it has a distinctive neural signature; and twin studies suggest specific heritability, though the relevant genes have not yet been identified. Unfortunately, educators and policymakers seem largely unaware of this cause, but appropriate interventions could alleviate the suffering and handicap of those with low numeracy, and would be a major benefit to society.This article is part of a discussion meeting issue 'The origins of numerical abilities'.

The principles and practices of educational neuroscience: Comment on Bowers (2016).

In his recent critique of Educational Neuroscience, Bowers argues that neuroscience has no role to play in informing education, which he equates with classroom teaching. Neuroscience, he suggests, adds nothing to what we can learn from psychology. In this commentary, we argue that Bowers' assertions misrepresent the nature and aims of the work in this new field. We suggest that, by contrast, psychological and neural levels of explanation complement rather than compete with each other. Bowers' analysis also fails to include a role for educational expertise-a guiding principle of our new field. On this basis, we conclude that his critique is potentially misleading. We set out the well-documented goals of research in Educational Neuroscience, and show how, in collaboration with educators, significant progress has already been achieved, with the prospect of even greater progress in the future. (PsycINFO Database Record

Zero in the brain: A voxel-based lesion-symptom mapping study in right hemisphere damaged patients.

Transcoding numerals containing zero is more problematic than transcoding numbers formed by non-zero digits. However, it is currently unknown whether this is due to zeros requiring brain areas other than those traditionally associated with number representation. Here we hypothesize that transcoding zeros entails visuo-spatial and integrative processes typically associated with the right hemisphere. The investigation involved 22 right-brain-damaged patients and 20 healthy controls who completed tests of reading and writing Arabic numbers. As expected, the most significant deficit among patients involved a failure to cope with zeros. Moreover, a voxel-based lesion-symptom mapping (VLSM) analysis showed that the most common zero-errors were maximally associated to the right insula which was previously related to sensorimotor integration, attention, and response selection, yet for the first time linked to transcoding processes. Error categories involving other digits corresponded to the so-called Neglect errors, which however, constituted only about 10% of the total reading and 3% of the writing mistakes made by the patients. We argue that damage to the right hemisphere impairs the mechanism of parsing, and the ability to set-up empty-slot structures required for processing zeros in complex numbers; moreover, we suggest that the brain areas located in proximity to the right insula play a role in the integration of the information resulting from the temporary application of transcoding procedures.

Numerical Activities and Information Learned at Home Link to the Exact Numeracy Skills in 5-6 Years-Old Children.

It is currently accepted that certain activities within the family environment contribute to develop early numerical skills before schooling. However, it is unknown whether this early experience influences both the exact and the approximate representation of numbers, and if so, which is more important for numerical tasks. In the present study the mathematical performance of 110 children (mean age 5 years 11 months) was evaluated using a battery that included tests of approximate and exact numerical abilities, as well as everyday numerical problems. Moreover, children were assessed on their knowledge of number information learned at home. The parents of the participants provided information regarding daily activities of the children and socio-demographic characteristics of the family. The results showed that the amount of numerical information learned at home was a significant predictor of participants' performance on everyday numerical problems and exact number representations, even after taking account of age, memory span and socio-economic and educational status of the family. We also found that particular activities, such as board games, correlate with the children's counting skills, which are foundational for arithmetic. Crucially, tests relying on approximate representations were not predicted by the numerical knowledge acquired at home. The present research supports claims about the importance and nature of home experiences in the child's acquisition of mathematics.

"My Mind Is Doing It All": No "Brake" to Stop Speech Generation in Jargon Aphasia.

OBJECTIVE: To study whether pressure of speech in jargon aphasia arises out of disturbances to core language or executive processes, or at the intersection of conceptual preparation. BACKGROUND: Conceptual preparation mechanisms for speech have not been well studied. Several mechanisms have been proposed for jargon aphasia, a fluent, well-articulated, logorrheic propositional speech that is almost incomprehensible. METHODS: We studied the vast quantity of jargon speech produced by patient J.A., who had suffered an infarct after the clipping of a middle cerebral artery aneurysm. We gave J.A. baseline cognitive tests and experimental word- and sentence-generation tasks that we had designed for patients with dynamic aphasia, a severely reduced but otherwise fairly normal propositional speech thought to result from deficits in conceptual preparation. RESULTS: J.A. had cognitive dysfunction, including executive difficulties, and a language profile characterized by poor repetition and naming in the context of relatively intact single-word comprehension. J.A.'s spontaneous speech was fluent but jargon. He had no difficulty generating sentences; in contrast to dynamic aphasia, his sentences were largely meaningless and not significantly affected by stimulus constraint level. CONCLUSIONS: This patient with jargon aphasia highlights that voluminous speech output can arise from disturbances of both language and executive functions. Our previous studies have identified three conceptual preparation mechanisms for speech: generation of novel thoughts, their sequencing, and selection. This study raises the possibility that a "brake" to stop message generation may be a fourth conceptual preparation mechanism behind the pressure of speech characteristic of jargon aphasia.

Ratio dependence in small number discrimination is affected by the experimental procedure.

Adults, infants and some non-human animals share an approximate number system (ANS) to estimate numerical quantities, and are supposed to share a second, 'object-tracking,' system (OTS) that supports the precise representation of a small number of items (up to 3 or 4). In relative numerosity judgments, accuracy depends on the ratio of the two numerosities (Weber's Law) for numerosities >4 (the typical ANS range), while for numerosities ≤4 (OTS range) there is usually no ratio effect. However, recent studies have found evidence for ratio effects for small numerosities, challenging the idea that the OTS might be involved for small number discrimination. Here we tested the hypothesis that the lack of ratio effect in the numbers 1-4 is largely dependent on the type of stimulus presentation. We investigated relative numerosity judgments in college students using three different procedures: a simultaneous presentation of intermingled and separate groups of dots in separate experiments, and a further experiment with sequential presentation. As predicted, in the large number range, ratio dependence was observed in all tasks. By contrast, in the small number range, ratio insensitivity was found in one task (sequential presentation). In a fourth experiment, we showed that the presence of intermingled distractors elicited a ratio effect, while easily distinguishable distractors did not. As the different ratio sensitivity for small and large numbers has been often interpreted in terms of the activation of the OTS and ANS, our results suggest that numbers 1-4 may be represented by both numerical systems and that the experimental context, such as the presence/absence of task-irrelevant items in the visual field, would determine which system is activated.

Anatomical substrates and neurocognitive predictors of daily numerical abilities in mild cognitive impairment.

Patients with mild cognitive impairment experience difficulties in mathematics that affect their functioning in the activities of everyday life. What are the associated anatomical brain changes and the cognitive correlates underlying such deficits? In the present study, 33 patients with Mild Cognitive Impairments (MCI) and 29 cognitively normal controls underwent volumetric MRI, and completed the standardized battery of Numerical Activities of Daily Living (NADL) along with a comprehensive clinical neuropsychological assessment. Group differences were examined on the numerical tasks and volumetric brain measures. The gray (GM) and white matter (WM) volume correlates were also evaluated. The results showed that relative to controls, the MCI group had impairments in number comprehension, transcoding, written operations, and in daily activities involving time estimation and money usage. In the volumetric measures, group differences emerged for the transcoding subtask in the left insula and left superior temporal gyrus. Among MCI patients, number comprehension and formal numerical performance were correlated with volumetric variability in the right middle occipital areas and right frontal gyrus. Money-usage scores showed significant correlations with left mesial frontal cortex, right superior frontal and right superior temporal cortex. Regression models revealed that neuropsychological measures of long-term memory, language, visuo-spatial abilities, and abstract reasoning were predictive of the patients' decline in daily activities. The present findings suggest that early neuropathology in distributed cortical regions of the brain including frontal, temporal and occipital areas leads to a breakdown of cognitive abilities in MCI that impacts on numerical daily functioning. The findings have implications for diagnosis, clinical and domestic care of patients with MCI.

Longitudinal changes in young children's 0-100 to 0-1000 number-line error signatures.

We use a latent difference score (LDS) model to examine changes in young children's number-line (NL) error signatures (errors marking numbers on a NL) over 18 months. A LDS model (1) overcomes some of the inference limitations of analytic models used in previous research, and in particular (2) provides a more reliable test of hypotheses about the meaning and significance of changes in NL error signatures over time and task. The NL error signatures of 217 6-year-olds' (on test occasion one) were assessed three times over 18 months, along with their math ability on two occasions. On the first occasion (T1) children completed a 0-100 NL task; on the second (T2) a 0-100 NL and a 0-1000 NL task; on the third (T3) occasion a 0-1000 NL task. On the third and fourth occasions (T3 and T4), children completed mental calculation tasks. Although NL error signatures changed over time, these were predictable from other NL task error signatures, and predicted calculation accuracy at T3, as well as changes in calculation between T3 and T4. Multiple indirect effects (change parameters) showed that associations between initial NL error signatures (0-100 NL) and later mental calculation ability were mediated by error signatures on the 0-1000 NL task. The pattern of findings from the LDS model highlight the value of identifying direct and indirect effects in characterizing changing relationships in cognitive representations over task and time. Substantively, they support the claim that children's NL error signatures generalize over task and time and thus can be used to predict math ability.

A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living.

The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities.

Collective enhancement of numerical acuity by meritocratic leadership in fish.

It has been known for more than a century that interacting people can generally achieve more accurate decisions than single individuals. Here we show that interacting guppy fish (Poecilia reticulata) achieve a superior level of numerosity discrimination well beyond the average ability of the isolated individual fish. This enhancement of numerical acuity was observed in dyadic interactions when (Experiment 1) the dyad chose which larger shoal of guppies to join and when (Experiment 2) the dyad chose the higher or the lower numerosity among two decision options after having learned the task individually. Dyadic accuracy and that of the more competent member of each dyad matched closely, supporting the hypothesis that meritocratic leadership arises spontaneously between dyadically interacting fish, rather than the 'many wrongs' principle that has been used to explain group superiority in many species.