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What are the geometric and information processing characteristics of elementary figures composed of simple physical dimensions? There have been a number of investigations of perception of rectangles, including debate about configurality (e.g., integrality and gestalt properties) as well as the prime perceptual dimensions. Yet, because of ambiguity even in the “right” definition of configurality and an absence of penetrating methodologies, there is still little known concerning the information processing of these patterns. To this end, the present study brings together two separate theory-driven methodologies, general recognition theory (GRT) and systems factorial technology (SFT). The first attacks the problem of dimensional interactions while the latter seeks to uncover process characteristics such as architecture, decisional stopping rules, and workload capacity. The same observers and as much as possible, the same stimuli were used in both approaches. Through our GRT analyses, we found strong evidence for dependencies between the percepts of height and width on both within-stimulus and cross-stimulus bases. Height perception was better with narrow widths and width perception was superior with short heights. In addition, a significant positive within-trial correlation of dimensions was evidenced within squares but not with rectangles. Our SFT initiative uncovered consistent signatures of parallelism paired with super capacity, the latter appearing both through the traditional conditioning on being correct and still present when modest speed accuracy trade-off was accounted for. Thus, the SFT and GRT inferences were quite compatible with a plausible cause of the positive correlations being across-channel facilitatory interactions which led to super capacity processing.

BackgroundIron deficiency (ID) and iron deficiency anemia (IDA) are highly-prevalent nutrient deficiencies and have been shown to have a range of negative effects on cognition and brain function. Human intervention studies including measures at three levels—blood, brain, and behavior—are rare and our objective was to model the relationships among measures at these three levels in school-going Indian adolescents.MethodsMale and female adolescents in rural India were screened for ID/IDA. Subjects consumed 2 meals/day for 6 months; half were randomly assigned to consume meals made from a standard grain (pearl millet) and half consumed meals made from an iron biofortified pearl millet (BPM). Prior to and then at the conclusion of the feeding trial, they completed a set of cognitive tests with concurrent electroencephalography (EEG).ResultsOverall, serum ferritin (sFt) levels improved over the course of the study. Ten of 21 possible measures of cognition showed improvements from baseline (BL) to endline (EL) that were larger for those consuming BPM than for those consuming the comparison pearl millet (CPM). Critically, the best model for the relationship between change in iron status and change in cognition had change in brain measures as a mediating factor, with both change in serum ferritin as a primary predictor and change in hemoglobin as a moderator.ConclusionsA dietary intervention involving a biofortified staple grain was shown to be efficacious in improving blood iron biomarkers, behavioral measures of cognition, and EEG measures of brain function. Modeling the relationships among these variables strongly suggests multiple mechanisms by which blood iron level affects brain function and cognition.Trial registrationRegistered at ClinicalTrials.gov,NCT02152150, 02 June 2014.

One vein of our research on psychological systems has focused on parallel processing models in disjunctive (OR) and conjunctive (AND) stopping-rule designs. One branch of that research has emphasized that a common strategy of inference in the OR situations is logically flawed. That strategy equates a violation of the popular Miller race bound with a coactive parallel system. Pointedly, Townsend & Nozawa (1997) revealed that even processing systems associated with extreme limited capacity are capable of violating that bound. With regard to the present investigation, previous theoretical work has proven that interactive parallel models with separate decision criteria on each channel can readily evoke capacity sufficiently super to violate that bound (e.~g., Colonius & Townsend, 1997; Townsend & Nozawa, 1995; Townsend & Wenger, 2004). In addition, we have supplemented the usual OR task with an AND task to seek greater testability of architectural, decisional, and capacity mechanisms (e.~g., Eidels et al., 2011; Eidels et al., 2015). The present study presents a broad meta-theoretical structure within which the past and new theoretical results are embedded. We further exploit the broad class of stochastic linear systems and discover that interesting classical results from Colonius (1990) can be given an elegant process interpretation within that class. In addition, we learn that conjoining OR with AND data affords an experimental test of the crucial assumption of context invariance, long thought to be untestable.

In their seminal study of chess expertise, Simon and Chase (Chase & Simon, 1973; Simon & Chase, 1973) proposed that perceptual learning was a necessary component of skill acquisition. In their view, acquisition of skill results from the strategic use of learning at multiple levels to adaptively overcome inherent limitations. The knowledge acquired by way of perceptual learning that supported increasingly sophisticated perceptual discrimination processes, according to Simon and Chase, was referred to as a chunk. The chunk was conceptualized as a meaningful complex set of features that abstracted the notion of a perceptual object. Simon and Chase further suggested that meaningful combinations of chunks could be combined to form configurations (Simon & Chase, 1973, p. 399). The present study addresses this idea by framing the notion of a chunk in terms of two formal metatheories, one that addresses representation (Ashby & Townsend, 1986) and one that addresses processing (Townsend & Nozawa, 1995), and tests the prediction that perceptual learning produces organized perceptual objects (chunks). Two experiments combine behavioral and electroencephelographic (EEG) measures to show that perceptual learning produces (a) a shift from perceptual independence and separability to violations of separability, and (b) shifts from limited-capacity serial processing to supercapacity parallel processing. The evidence from both experiments is strong and consistent: perceptual learning does indeed induce chunking-the production of perceptual objects, and the foundation of perceptual expertise. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Iron deficiency (ID) and iron deficiency anemia (IDA) are highly-prevalent nutrient deficiencies and have been shown to have a range of negative effects on cognition and brain function. Human intervention studies including measures at three levels-blood, brain, and behavior-are rare and our objective was to model the relationships among measures at these three levels in school-going Indian adolescents.Male and female adolescents in rural India were screened for ID/IDA. Subjects consumed 2 meals/day for 6 months; half were randomly assigned to consume meals made from a standard grain (pearl millet) and half consumed meals made from an iron biofortified pearl millet (BPM). Prior to and then at the conclusion of the feeding trial, they completed a set of cognitive tests with concurrent electroencephalography (EEG).Overall, serum ferritin (sFt) levels improved over the course of the study. Ten of 21 possible measures of cognition showed improvements from baseline (BL) to endline (EL) that were larger for those consuming BPM than for those consuming the comparison pearl millet (CPM). Critically, the best model for the relationship between change in iron status and change in cognition had change in brain measures as a mediating factor, with both change in serum ferritin as a primary predictor and change in hemoglobin as a moderator.A dietary intervention involving a biofortified staple grain was shown to be efficacious in improving blood iron biomarkers, behavioral measures of cognition, and EEG measures of brain function. Modeling the relationships among these variables strongly suggests multiple mechanisms by which blood iron level affects brain function and cognition.Registered at ClinicalTrials.gov, NCT02152150 , 02 June 2014.

OBJECTIVES: Smoking cessation research suggests that women are more likely than men to respond to financial incentives to quit smoking, despite having lower rates of smoking cessation overall. Animal models suggest that iron deficiency, which is more prevalent in women, may alter dopaminergic pathways involved in both reward processing and addiction. The present study examines the extent to which iron status impacts ability to quit smoking and performance on a battery of cognitive tasks, including tasks assessing learning and decision-making which depend on the integrity of the dopaminergic pathways. METHODS: Participants were recruited from a local smoking cessation clinic and followed for 6 months as they received counseling to quit smoking. Visits included a baseline appointment, as well as 1- and 6-month follow up visits. At each appointment, participants performed cognitive tests, including the serial reaction time task (SRT) and probabilistic selection task (PST), with concurrent EEG, then gave a small sample of blood. Smoking behavior was examined using time to relapse (TTR), which was the week (1–26) in which the participant relapsed, if relapse occurred. Iron status variables of interest were hemoglobin (Hb) and percentile of the NHANES III age- and race-adjusted distributions of serum ferritin (sFtP). Correlations examined the associations between iron status variables and reaction times (RTs) on the SRT and PST, choice behavior on PST, and TTR. RESULTS: TTR was positively related to sFtP (r = 0.79, P

Much progress has been made in the investigation of perceptual, cognitive, and action mechanisms under the assumption that when one subprocess precedes another, the first one starts and finishes before the other begins. We call such processes "Dondersian" after the Dutch physiologist who first formulated this concept. Serial systems obey this precept (e.g., Townsend, 1974). However, most dynamic systems in nature do not: instead, each subprocess communicates its state to its immediate successors continuously. Although the mathematics for physical systems has received extensive treatment over the last three centuries, applications to human cognition have been exiguous. Therefore, the pioneering papers by Charles Eriksen and colleagues on continuous flow dynamics (e.g., Eriksen & Schulz, Perception & Psychophysics, 25, 249-263, 1979; Coles et al.,, Journal of Experimental Psychology: Human Perception and Performance, 11(5), 529, 1985) must be viewed as truly revolutionary. Surprisingly, there has been almost no advancement on this front since. With the goal of bringing this theme back into the scientific consciousness and extending and deepening our understanding of such systems, we develop a taxonomy that emphasizes the fundamental characteristics of continuous flow dynamics. Subsequently, we complexify the treated systems in such a way as to illustrate the popular cascade model (Ashby, Psychological Review, 89, 599-607, 1982; McClelland, Psychological Review, 86, 287-330, 1979) and use it to simulate the classic findings of Eriksen and colleagues (Eriksen & Hoffman, Perception & Psychophysics, 12(2), 201-204, 1972).

The present study used information theory to quantify the extent to which different spatial cues conveyed the entropy associated with the identity and location of a visual search target. Single-distribution cues reflected the probability that the target would appear at one fixed location whereas joint-distribution cues reflected the probability that the target would appear at the location where another cue (arrow) pointed. The present study used a novel demand-selection paradigm to examine the extent to which individuals explicitly preferred one type of probability cue over the other. Although both cues conveyed equal entropy, the main results suggested representation of greater target entropy for joint- than for single-distribution cues based on a comparison between predicted and observed probability cue choices across four experiments. The present findings emphasize the importance of understanding how individuals represent basic information-theoretic quantities that underlie more complex decision-theoretic processes such as Bayesian and active inference.

Musical training is required for individuals to correctly label musical modes using the terms "major" and "minor," whereas no training is required to label these modes as "happy" or "sad." Despite the high accuracy of nonmusicians in happy/sad labeling, previous research suggests that these individuals may exhibit differences in the neural response to the critical note-the note (the third of the relevant key) that defines a melody as major or minor. The current study replicates the presence of a late positive component (LPC) to the minor melody in musicians only. Importantly, we also extend this finding to examine additional neural correlates of critical notes in a melody. Although there was no evidence of an LPC response to a second occurrence of the critical note in either group, there was a strong early right anterior negativity response in the inferior frontal gyrus in musicians in response to the first critical note in the minor mode. This response was sufficient to classify participants based on their musical training group. Furthermore, there were no differences in prefrontal asymmetry in the alpha or beta bands during the critical notes. These findings support the hypothesis that musical training may enhance the neural response to the information content of critical note in a minor scale but not the neural response to the emotional content of a melody.

BACKGROUND Iron deficiency remains the most prevalent micronutrient deficiency globally, but few studies have examined how iron status relates to cognition in adolescents. Iron biofortification of staple food crops is being scaled up, yet it is unknown whether consuming biofortified crops can benefit cognition. Objective Our objective was to determine the efficacy of iron-biofortified pearl millet in improving attention and memory in Indian school-going adolescents. Methods A double-blind, randomized, intervention study was conducted in 140 Indian boys and girls, aged 12-16 y, who were assigned to consume iron-biofortified [Fe = 86 parts per million (ppm)] or conventional (Fe = 21-52 ppm) pearl millet. Hemoglobin, ferritin, and transferrin receptor (TfR) were measured and body iron (BI) was calculated at baseline and after 4 and 6 mo. Five measures of cognitive function were obtained at baseline and 6 mo: simple reaction time (SRT), Go/No-Go (GNG) task, Attentional Network Task (ANT), Composite Face Effect (CFE) task, and Cued Recognition Task (CRT). Intention-to-treat analysis was used. Results Daily iron intake from pearl millet was higher in those consuming biofortified compared with conventional pearl millet (19.6 compared with 4.8 mg/d). Effects on ferritin, TfR, and BI at 4 mo, and on TfR at 6 mo (all P

OBJECTIVES: Iron deficiency (ID)—a highly-prevalent nutritional deficiency—has been shown to have deleterious effects on measures of cognitive performance and brain activity. Many of these results are suggestive of the impact of ID on neurotransmitter regulation and myelination. A third critical potential effect of ID on brain function is at the level of brain energy expenditure, however to date there has not been any method for indirectly estimating the impact of ID on energy expenditure in humans in the context of cognitive work. METHODS: We report here a study comparing ID and iron sufficient (IS) college students in which simultaneous behavioral, electrophysiological (EEG), and metabolic data were collected in a task designed as a cognitive analog to standard physical exertion tasks. RESULTS: We show that increases in cognitive demands produced decrements in behavioral measures of performance, and increases in EEG and metabolic measures of work. Critically, we found that the magnitudes of those changes were directly related to iron levels. DISCUSSION: We find support for the idea that brain activity mediates the relationship between cognitive demands and energy expenditure, with ferritin and hemoglobin moderating those relationships in distinct ways. Finally, we show that levels of energy expenditure can be indirectly estimated by measures of EEG spectral power.

Background: Iron deficiency is a global public health concern and has implications on the health status of women in reproductive age. Objective: We hypothesized that improving iron intake with double fortified salt would improve food intake, resulting in higher energy, nutrient intakes, and weight indicators of female tea plantation workers. Methods: In this randomized double-masked study, the participants (n = 245) were assigned to receive salt double fortified with iron and iodine (DFS; treatment) or salt fortified with iodine (control) and followed for 7.5 to 9 months. Dietary intakes were measured at three time points, baseline, midpoint, and end line using (1) food frequency questionnaire, (2) 24-hour recall, and (3) weighed lunch intake. Anthropometric measures of height (cm), weight (kg), and mid-upper arm circumference (cm) were also recorded at three time points. Mixed-model repeated-measures approach was used to detect group differences across time. Results: Double fortified salt improved dietary iron intake in the treatment group compared to the control group ( P < .001). No other dietary or anthropometric differences could be attributed to treatment. Significant effect of time was observed in the intake frequency of major food groups and calcium, vitamin A and C ( P Conclusion: Addition of DFS in the diet improved dietary iron intake but did not affect the intake of energy, other nutrients, or nutritional status indicators. The improvement observed in the dietary iron intake demonstrates that fortification is an effective strategy to address iron deficiency in at-risk populations.

Background: Cognitive complaints (“chemo brain”) are reported frequently after breast cancer treatment but little is known about its incidence and causes. Before we can intervene we need to be able to diagnose it properly. Mini Mental state examination (MMSE) can detect advanced Alzheimer's but won't help in detecting mild cognitive disturbances. We used Montreal Cognitive Assessment for Telephone (MoCA-T) and full scale Montreal Cognitive Assessment for Telephone (MoCA) to diagnose mild cognitive impairments in patients having normal MMSE. Methods: 20 breast cancer survivors aged 50 years or older completed MoCA-T and MoCA, a year after they completed their treatment for breast cancer, describing the impact of their treatment regimen on their short term memory and ability to think and concentrate. On Day 5, they underwent a standardized laboratory protocol that assessed both behavioral and electroencephalographic (EEG) indicators of memory consolidation. Results: Patient characteristics: 20 postmenopausal breast cancer survivors aged 50 or above participated in the study a year after they completed their therapy. We are reporting preliminary results of 10 patients. Patients had stage I-III disease (stage I – One patient, Stage II – five patients, and stage III- four patients). All of them received various chemo regimens e.g. Cytoxan, methotrexate, 5-FU (CMF), Taxol, Trastuzumab (TH), Adriamycin (AC), taxotere, carboplatin (TCH). 8/10 patients received adjuvant radiation. 1/10 patient underwent reconstruction later. 7/10 patients received hormonal therapy with aromatase inhibitors. Results of MoCA –T and MoCA: MoCA-T, tests attention and concentration, executive functions, memory, language, conceptual thinking, calculations, and orientation. Possible scores range from 0-22 and scores 26 is normal but 5/10 patients had abnormal MoCA and 3/10 patients had impaired MoCA-T signifying that almost 50%patients develop mild cognitive impairment after breast cancer treatment. During memory consolidation, EEG contained less theta and frequent bursts of alpha waves which is commonly seen in patients with neuropathic pain and insomnia. MoCA-T and MoCA results for the patientsPatient no.MoCA-TMoCAPtient 00817*23*Patient 0102126Patient 0111923*Patient 01216*27Patient 0132027Patient 01517*21*Patient 0161824*Patient 0172025*Patient 0191926Patient 0202129*presents affected patient Conclusions: The study signifies that mild cognitive impairment from breast cancer treatment (or “chemo brain”) was frequently reported and MoCA-T and MoCA tests were able to show even mild cognitive impairment in these patients. We are compiling our full data for EEG but the early results show that the patients had less theta but had frequent bursts of alpha waves, a pattern seen commonly in patients with insomnia and neuropathic pain. They retain fewer items and take more time responding to items as compared to normal people. We need more studies to diagnose and treat mild cognitive impairment (“chemo brain”) in breast survivors as most of these patients are still working and can be a valuable part of the community. Citation Format: Razaq WA, Tanaka T, Carlson B, Wenger M, Friedman J, Benbrook D, Craft M. Diagnosing cognitive impairment (“chemo brain”) in breast cancer survivors [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-20-09.

OBJECTIVES: The present study sought to determine the possibility of identifying someone as either iron deficient or sufficient based solely on brain activity, and, if possible, how quickly (based on processing time on a cognitive task) this could be done. METHODS: Both iron sufficient(IS) and iron deficient non-anemic (IDNA) females (mean age 21.1 y) learned two visual categorization tasks while concurrent EEG was acquired. Both tasks involved classifying gray-scale gabor patches on the basis of spatial frequency and orientation; one task used an easily-verbalized rule (rule-based, RB), the other required complex integration of the information (II). Moving windows (20 ms width) of EEG data from 100 electrodes were used to predict the participant's iron status using logistic regression; model form was determined using stepwise variable selection. The outcome variable was the area under the curve (AUC) of the receiver operating characteristic for the classification. We set a criterion of AUC ≥ 0.80 for successful classification performance. RESULTS: For both tasks, successful classification was possible before 200 ms of processing on the basis of fewer than 12 electrodes. Classification in the RB task suggested some early right lateralization in the selection of electrodes, which became more central as processing proceeded. Classification in the II task did not suggest lateralization, although there was some change to more central electrodes as processing proceeded. At each 20 ms time window, for each of the selected set of electrodes, a measure of neural efficiency was calculated as the ratio of the hazard function of the reaction time distribution and the global field power of the selected set of electrodes. This ratio can be interpreted as the amount of work accomplished per unit of energy expended. In all cases, neural efficiency for the IS females exceeded that for the IDNA females, suggesting that the efficiency with which neural energy is expended in cognitive work differs as a function of iron status. CONCLUSIONS: Iron deficiency without anemia results in distinct patterns of brain activity early in processing that reflect reduced levels of neural efficiency, relative to females who are iron sufficient. FUNDING SOURCES: OU Office of the Vice President for Research.

Background The literature on correlates of nutrition has seen an increase in studies focused on functional consequences at the levels of neural, perceptual, and cognitive functioning. A range of measurement methodologies have been used in these studies, and investigators and funding agencies have raised the questions of how and if these various methodologies are at all comparable. Objective The aim was to determine the extent to which 3 different sets of cognitive measures provide comparable information across 2 subsamples that shared culture and language but differed in terms of socioeconomic status (SES) and academic preparation. Methods A total of 216 participants were recruited at 2 US universities. Each participant completed 3 sets of cognitive measures: 1 custom-designed set based on well-understood laboratory measures of cognition [cognitive task battery (COGTASKS)] and 2 normed batteries [Cambridge Neuropsychological Test Automated Battery (CANTAB), Weschler Adult Intelligence Scale, fourth edition (WAIS-IV)] designed for assessing general cognitive function. Results The 3 sets differed with respect to the extent to which SES and educational preparation affected the results, with COGTASKS showing no differences due to testing location and WAIS-IV showing substantial differences. There were, at best, weak correlations among tasks sharing the same name or claiming to measure the same construct. Conclusions Comparability of measures of cognition cannot be assumed, even if measures have the same name or claim to assess the same construct. In selecting and evaluating different measures, construct validity and underlying biological mechanisms need to be at least as important as population norms and the ability to connect with existing literatures.

This paper proposes a novel approach to assess audiovisual integration for both congruent and incongruent speech stimuli using reaction times (RT). The experiments are based on the McGurk effect, in which a listener is presented with incongruent audiovisual speech signals. A typical example involves the auditory consonant/b/combined with a visually articulated/g/, often yielding a perception of/d/. We quantify the amount of integration relative to the predictions of a parallel independent model as a function of attention and congruency between auditory and visual signals. We assessed RT distributions for congruent and incongruent auditory and visual signals in a within-subjects signal detection paradigm under conditions of divided versus focused attention. Results showed that listeners often received only minimal benefit from congruent auditory visual stimuli, even when such information could have improved performance. Incongruent stimuli adversely affected performance in divided and focused attention conditions. Our findings support a parallel model of auditory-visual integration with interactions between auditory and visual channels.

Background: Iron deficiency is the most widespread nutritional deficiency in the world. Objective: The objective of this randomized efficacy trial was to determine the effects of iron-biofortified pearl millet (FePM) on iron status compared with control pearl millet (Control-PM). Methods: A randomized trial of biofortified pearl millet (Pennisetum glaucum), bred to enhance iron content, was conducted in 246 children (12‐16 y) for 6 mo in Maharashtra, India. Iron status [hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), and total body iron (TBI)], inflammation (C-reactive protein and a-1 acid glycoprotein), and anthropometric indices were evaluated at enrollment and after 4 and 6 mo. Hodges-Lehmann-Sen 95% CIs were used to examine the effect of the Fe-PM on iron status compared with commercially available Control-PM. Linear and binomial regression models were usedtoevaluatetheeffectsofFe-PM onironstatusandincidence ofanemiaandirondeficiency,compared withControl-PM. Results: At baseline, 41% of children were iron deficient (SF

The uncertainty paradigm has been used in vision research to evaluate whether stimulus components are processed independently or not. The paradigm consists of several experimental conditions from which sensitivity indices are estimated and combined to provide evidence for or against the independence of stimulus components in perception. In typical applications, a multicomponent stimulus differs in one of its components from a standard value and the observer needs to decide if the change is an increment or decrement. In the certainty condition, the observer knows which component will contain the change; in the uncertainty condition, the component that differs from standard is unknown. Performance across the two conditions can be compared to that which is predicted by independence of components. The mathematical foundations upon which performance indices are related to component independence have been inadequately examined in previous applications and we clarify many of these concepts here. We derive predictions for observer sensitivity in the uncertainty condition and a relative measure, root-mean-square (RMS) that incorporates both uncertainty and certainty performance for three major decision models using a signal detection theory framework: a distance-classifier, the optimal decision model, and a decisionally separable (“independent” decisions) strategy. We also consider, using these decision models, implications for sensitivity and RMS when stimulus components are perceptually correlated. We present data from an experiment involving the perception of facial features in order to demonstrate how to apply the theoretical results.

Theoretical analyses suggest that the regularities indicative of holistic processing can be obtained by combinations of perceptual and decisional factors. Kuefner and colleagues used electrophysiological results to suggest that the composite face effect is driven solely by perceptual factors. Two limitations of their approach are (a) it did not involve behavioral measures of perceptual sensitivity or bias, and (b) it is unclear how the measures used in that study are consistent with other measures of perceptual and decisional processing. Eight observers completed three tasks involving the stimuli used by Kuefner et al.. The first was a direct replication. The second was a complete identification task, associated with the perceptual and decisional distinctions formalized in general recognition theory. The third was an implementation of the Eriksen fianker task, which allows for a pattern of results that have been interpreted in terms of perceptual and decisional influences. While the empirical distinctions used by Kuefner et al. were not consistent with either the EEG data from the other tasks or the established behavioral measures of perceptual sensitivity and decisional bias, the inferences drawn from the EEG and behavioral data from those tasks were consistent with one another, underscoring the importance of converging operations.

Background: Iron deficiency and iron deficiency anemia have been shown to have negative effects on aspects of perception, attention, and memory. Objective: The purpose of this investigation was to assess the extent to which increases in dietary iron consumption are related to improvements in behavioral measures of perceptual, attentional, and mnemonic function. Methods: Women were selected from a randomized, double-blind, controlled food-fortification trial involving ad libitum consumption of either a double-fortified salt (DFS) containing 47 mg potassium iodate/kg and 3.3 mg microencapsulated ferrous fumarate/g (1.1 mg elemental Fe/g) or a control iodized salt. Participants’ blood iron status (primary outcomes) and cognitive functioning (secondary outcomes) were assessed at baseline and after 10 mo at endline. The study was performed on a tea plantation in the Darjeeling district of India. Participants (n = 126; 66% iron deficient and 49% anemic at baseline) were otherwise healthy women of reproductive age, 18–55 y. Results: Significant improvements were documented for iron status and for perceptual, attentional, and mnemonic function in the DFS group (percentage of variance accounted for: 16.5%) compared with the control group. In addition, the amount of change in perceptual and cognitive performance was significantly (P < 0.05) related to the amount of change in blood iron markers (mean percentage of variance accounted for: 16.0%) and baseline concentrations of blood iron markers (mean percentage of variance accounted for: 25.0%). Overall, there was evidence that the strongest effects of change in iron status were obtained for perceptual and low-level attentional function. Conclusion: DFS produced measurable and significant improvements in the perceptual, attentional, and mnemonic performance of Indian female tea pickers of reproductive age. This trial was registered at clinicaltrials.gov as NCT01032005.

Amnestic Mild Cognitive Impairment (aMCI), a condition in which the memory functions of cognition are significantly impaired, is an established risk factor for Alzheimer's disease. Electroencephalography (EEG) is a tool capable of measuring the dynamics of the brain's neural networks, and is thus an important means in analysis and understanding of aMCI. In this proof-of-concept study, we compared the brain activation patterns of ten aMCI subjects with those of four healthy subjects during sleep by employing a 64-channel EEG data collection system. The power spectrum was analyzed to identify sleep stages, while spectral topography and source imaging techniques were employed to study the fluctuating patterns of the brain. Results of this study show an increase in activation power across all sleep stages in the delta and theta frequency bands alongside a decrease in alpha band activity for aMCI subjects. Source imaging analysis of the resting EEG identified default mode network, which becomes decoupled as sleep stages deepen. In the proof-of-concept study, our exploratory analysis demonstrated the feasibility of imaging dynamic network organization using EEG in aMCI.

Background: Evidence shows that iron deficiency in adulthood may affect cognitive performance, possibly by disrupting neurotransmitter regulation or brain energy metabolism. Women of reproductive age (WRA) are among those who are most vulnerable to iron deficiency; however, they have been largely ignored in the literature relating iron status to cognition. Objective: Our aim was to determine the efficacy of iron-biofortified beans in improving cognition in WRA compared with control beans. Methods: A double-blind, randomized intervention study was conducted in 150 women aged 18–27 y with low iron status (ferritin 2-fold greater improvement in the specificity of memory retrieval; and a >2-fold larger improvement in the speed and a >3-fold larger improvement in the efficiency of memory search—all of which are relative to consumption of the control beans (P < 0.01 for all comparisons). Conclusions: Cognitive performance is sensitive to iron status, and consumption of iron-biofortified beans for 18 wk improved cognitive performance, especially the efficiency of search and the speed of retrieval on memory tasks, in young adult women. This trial was registered at clinicaltrials.gov as NCT01594359.

Two of the most prominent strengths of the conjoined metatheory and methodology in systems factorial theory and the double-factorial paradigm (SFT/DFP) are its generality and its emphasis on strong-inference hypothesis testing. The intellectual history of SFT/DFP shows that these two strengths have been central to the evolution of this approach. We review that intellectual history by considering two critical predecessors—the parallel–serial testing paradigm, and the trichotomy method—and by briefly reviewing a range of studies that have applied the approach. We close by presenting a new application that illustrates and emphasizes the generality of DFT/DFP by showing how the approach can be used with the timing of neural events.

Right visual field-left hemisphere (RVF-LH) and left visual field-right hemisphere (LVF-RH) specialisations found for categorical and coordinate visuospatial judgements, respectively, are thought to demonstrate two different perceptual processes. In the current experiment, we used signal detection theory to investigate categorical and coordinate processes, and to explore the relationship between response time (RT), sensitivity and bias measures. We found a LVF-RH advantage for the processing of categorical spatial relations when this effect was indexed by sensitivity. We also found that task influenced response bias in RVF-LH trials, but not in LVF-RH trials. Increased sensitivity was correlated with faster responses in the coordinate task but slower responses in the categorical task, and faster RTs when responding liberally in RVF-LH but not LVF-RH categorical trials. By analysing signal detection measures alongside RT, the findings suggest that differences in sensitivity and response bias may contribute to typical task by hemisphere effects in RT.

The ability to effectively combine sensory inputs across modalities is vital for acquiring a unified percept of events. For example, watching a hammer hit a nail while simultaneously identifying the sound as originating from the event requires the ability to identify spatio-temporal congruencies and statistical regularities. In this study, we applied a reaction time and hazard function measure known as capacity (e.g., Townsend and AshbyCognitive Theory 200-239, 1978) to quantify the extent to which observers learn paired associations between simple auditory and visual patterns in a model theoretic manner. As expected, results showed that learning was associated with an increase in accuracy, but more significantly, an increase in capacity. The aim of this study was to associate capacity measures of multisensory learning, with neural based measures, namely mean global field power (GFP). We observed a co-variation between an increase in capacity, and a decrease in GFP amplitude as learning occurred. This suggests that capacity constitutes a reliable behavioral index of efficient energy expenditure in the neural domain.

We propose a measure of audiovisual speech integration that takes into account accuracy and response times. This measure should prove beneficial for researchers investigating multisensory speech recognition, since it relates to normal-hearing and aging populations. As an example, age-related sensory decline influences both the rate at which one processes information and the ability to utilize cues from different sensory modalities. Our function assesses integration when both auditory and visual information are available, by comparing performance on these audiovisual trials with theoretical predictions for performance under the assumptions of parallel, independent self-terminating processing of single-modality inputs. We provide example data from an audiovisual identification experiment and discuss applications for measuring audiovisual integration skills across the life span.

A prominent theory in the face perception literature—the parallel-route hypothesis (Bruce & Young, 1986)—assumes a dedicated channel for the processing of identity that is separate and independent from the channel(s) in which nonidentity information is processed (e.g., expression, eye gaze). The current work subjected this assumption to experimental tests from the perspective of three characterizations of independence and separability: Garner’s speeded classification task (Garner, 1974), general recognition theory (Ashby & Townsend, 1986), and systems factorial technology (Townsend & Nozawa, 1995). The goals of the study were to (a) provide converging evidence on validity of the parallel-route hypothesis, and (b) understand the relationships between various definitions of independence and separability. The results of the current work demonstrated that identity and expression are not completely independent, using data from all three perspectives. Consequently, a modification of the central assumption of the parallel-route hypothesis is required. In addition, the intricate but orderly relationships between various types of separability and independence have implications for theories of perceptual independence.

What factors contribute to redundant target processing speed besides statistical facilitation? one possibility is that multiple percepts may drive these effects. Another, although not mutually exclusive hypothesis, is that cross- channel cueing from one modality to another may influence response times. We implemented an auditory–visual detection task using the sound- induced flash illusion to examine whether one or both of these possibilities contributes to changes in processing speed; we did so by examining the data of individual participants. our results indicated shorter response times in several participants when multiple flashes were perceived in the standard sound- induced flash illusion, thereby replicating previous work in the literature. Additionally, we found evidence for faster responses in several participants when carrying out the same analysis in trials in which 1 beep was presented with 2 real flashes. overall, our analysis indicates that some observers benefit from cross- modal facilitation, whereas others may benefit from a combination of cross- modal facilitation and increased perceptual judgments.

The Thatcher illusion (Thompson, 1980) is considered to be a prototypical illustration of the notion that face perception is dependent on configural processes and representations. We explored this idea by examining the relative contributions of perceptual and decisional processes to the ability of observers to identify the orientation of two classes of forms-faces and churches-and a set of their component features. Observers were presented with upright and inverted images of faces and churches in which the components (eyes, mouth, windows, doors) were presented either upright or inverted. Observers first rated the subjective grotesqueness of all of the images and then performed a complete identification task in which they had to identify the orientation of the overall form and the orientation of each of the interior features. Grotesqueness ratings for both classes of image showed the standard modulation of rated grotesqueness as a function of orientation. The complete identification results revealed violations of both perceptual and decisional separability but failed to reveal any violations of within-stimulus (perceptual) independence. In addition, exploration of a simple bivariate Gaussian signal detection model of the relationship between identification performance and judged grotesqueness suggests that within-stimulus violations of perceptual independence on their own are insufficient for producing the illusion. This lack of evidence for within-stimulus configurality suggests the need for a critical reevaluation of the role of configural processing in the Thatcher illusion. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Variations in perceptual and cognitive demands (load) play a major role in determining the efficiency of selective attention. According to load theory (Lavie, Hirst, Fockert, & Viding, 2004) these factors (a) improve or hamper selectivity by altering the way resources (e.g., processing capacity) are allocated, and (b) tap resources rather than data limitations (Norman & Bobrow, 1975). Here we provide an extensive and rigorous set of tests of these assumptions. Predictions regarding changes in processing capacity are tested using the hazard function of the response time (RT) distribution (Townsend & Ashby, 1978; Wenger & Gibson, 2004). The assumption that load taps resource rather than data limitations is examined using measures of sensitivity and bias drawn from signal detection theory (Swets, 1964). All analyses were performed at two levels: the individual and the aggregate. Hypotheses regarding changes in processing capacity were confirmed at the level of the aggregate. Hypotheses regarding resource and data limitations were not completely supported at either level of analysis. And in all of the analyses, we observed substantial individual differences. In sum, the results suggest a need to expand the theoretical vocabulary of load theory, rather than a need to discard it.

Biofortification is the breeding of crops to increase their nutritional value, including increased contents of micronutrients or their precursors. Biofortification aims to increase nutrient levels in crops during plant growth rather than during processing of the crops into foods. Emerging research from 8 human trials conducted in the past decade with staple food crops that have been biofortified by traditional plant breeding methods were presented in this symposium. Specifically, data from 6 efficacy and 2 effectiveness trials were discussed to assess the effects of regular consumption of these enhanced staple crops on improving population vitamin A and iron status and reducing the burden of micronutrient deficiencies in targeted populations living in South Asia, Sub-Saharan Africa, and Latin America. Biofortified food crops appear to have a positive impact on nutritional and functional health outcomes, as the results from the trials suggest. Additional implementation research will be needed to ensure maximization of the beneficial impact of this intervention and a smooth scaling up to make biofortification a sustainable intervention in public health. The challenge for the global health community remains how to take this efficacious intervention and implement at large scale in the real world.

Epistemic actions are physical actions people take to simplify internal problem solving rather than to move closer to an external goal. When playing the video game Tetris, for instance, experts routinely rotate falling shapes more than is strictly needed to place the shapes. Maglio and Kirsh [Kirsh, D., & Maglio, P. (1994). On distinguishing epistemic from pragmatic action. Cognitive Science, 18, 513-549; Maglio, P. P. (1995). The computational basis of interactive skill. PhD thesis, University of California, San Diego] proposed that such actions might serve the purpose of priming memory by external means, reducing the need for internal computation (e.g., mental rotation), and resulting in performance improvements that exceed the cost of taking additional actions. The present study tests this priming hypothesis in a set of four experiments. The first three explored precisely the conditions under which priming produces benefits. Results showed that presentation of multiple orientations of a shape led to faster responses than did presentation of a single orientation, and that this effect depended on the interval between preview and test. The fourth explored whether the benefit of seeing shapes in multiple orientations outweighs the cost of taking the extra actions to rotate shapes physically. Benefits were measured using a novel statistical method for mapping reaction-time data onto an estimate of the increase in processing capacity afforded by seeing multiple orientations. Cost was measured using an empirical estimate of time needed to take action in Tetris. Results showed that indeed the increase in internal processing capacity obtained from seeing shapes in multiple orientations outweighed the time to take extra actions.

Researchers have used several composite face paradigms to assess holistic processing of faces. In the selective attention paradigm, participants decide whether one face part (e.g., top) is the same as a previously seen face part. Their judgment is affected by whether the irrelevant part of the test face is the same as or different than the relevant part of the study face. This failure of selective attention implies holistic processing. However, the authors show that this task alone cannot distinguish between perceptual and decisional sources of holism. The distinction can be addressed by the complete identification paradigm, in which both face parts are judged to be same or different, combined with analyses based on general recognition theory (F. G. Ashby & J. T. Townsend, 1986). The authors used a different paradigm, sequential responses, to relate these 2 paradigms empirically and theoretically. Sequential responses produced the same results as did selective attention and complete identification. Moreover, disruptions of holistic processing by systematic misalignment of the faces corresponded with systematic and significant changes in the decisional components, but not in the perceptual components, that were extracted using general recognition theory measures. This finding suggests a significant decisional component of holistic face processing in the composite face task.

BACKGROUND Food-based strategies to reduce nutritional iron deficiency have not been universally successful. Biofortification has the potential to become a sustainable, inexpensive, and effective solution. OBJECTIVE This randomized controlled trial was conducted to determine the efficacy of iron-biofortified beans (Fe-Beans) to improve iron status in Rwandan women. METHODS A total of 195 women (aged 18-27 y) with serum ferritin

Iron deficiency (ID) in otherwise healthy adults can impair perceptual and cognitive functioning, along with brain dynamics (as measured by EEG). We used structural equation modeling (SEM) to test the hypothesis that changes in iron status lead to changes in brain functioning and then to changes in behavioral measures. The data used here were taken from 54 ID (sFt