Hasan Ayaz

Drexel University | DU · School of Biomedical Engineering, Science and Health Systems

The understanding of the brain functioning in the real world is the next frontier: discovering its operational principles, architectural design, and internal mechanisms are attributed as a significant opportunity to advance human civilization (National Academy of Engineering, 2008). How low-level brain processes translate into cognition is one of t...

Training to master a new skill often takes a lot of time, effort, and financial resources, particularly when the desired skill is complex, time sensitive, or high pressure where lives may be at risk. Professions such as aircraft pilots, surgeons, and other mission-critical operators that fall under this umbrella require extensive domain-specific de...

Until recently, neural assessments of gross motor coordination could not reliably handle active tasks, particularly in realistic environments, and offered a narrow understanding of motor-cognition. By applying a comprehensive neuroergonomic approach using optical mobile neuroimaging, we probed the neural correlates of motor functioning in young peo...

This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive hu...

Recent advances in neuroscience and engineering have allowed increasingly accessible, mobile, and wearable neurotechnologies that can record or alter human brain activity in natural everyday settings. Following significant conceptual and methodological improvements within the last decades, portable neuroimaging sensors are now widely adopted to stu...

Objective: Introduction of brain hypoxia by frequent mask-wearing is a concern voiced by some who resist masking mandates. Studies have examined acute effects of one-shot mask-wearing on peripheral and cerebral oxygenation in the laboratory, but not effects of everyday mask-wearing frequencies on task-related functional activation. The objective of...

This work describes a unique ultrasound exposure system designed to create very localized (~100μm) sound fields at operating frequencies that are currently being used for pre-clinical ultrasound neuromodulation. This system can expose small clusters of neuronal tissue, such as cell cultures or intact brain structures in target animal models, openin...

Background: Gait deficits are common after concussion in adolescents. However, the neurophysiological underpinnings of these gait deficiencies are currently unknown. Thus, the goal of this study was to compare spatiotemporal gait metrics, prefrontal cortical activation, and neural efficiency between concussed adolescents several weeks from injury...

There is concern that repetitive head impact exposure (RHIE) may lead to neurophysiological deficits in adolescents. Twelve high school varsity soccer players (5 female) completed the King-Devick (K-D) and complex tandem gait (CTG) assessments pre- and post-season while wearing a functional near-infrared spectroscopy (fNIRS) sensor. The average hea...

There is a gap in our understanding of how best to apply transcranial direct-current stimulation (tDCS) to enhance learning in complex, realistic, and multifocus tasks such as aviation. Our goal is to assess the effects of tDCS and feedback training on task performance, brain activity, and connectivity using functional magnetic resonance imaging (f...

Developmental coordination disorder (DCD) is characterized by motor learning deficits that are poorly understood within whole-body activities context. Here we present results of one of the largest non-randomized interventional trials combining brain imaging and motion capture techniques to examine motor skill acquisition and its underpinning mechan...

Purpose: Difficulty reappraising drives to consume palatable foods may promote poorer inhibition and binge eating (BE) in adults with obesity, but neural underpinnings of food-related reappraisal are underexamined. Methods: To examine neural correlates of food-related reappraisal, adults with obesity with and without BE wore a portable neuroimag...

BackgroundThere is a gap in our understanding of how best to apply transcranial direct current stimulation (tDCS) to enhance learning in complex, realistic, and multi-focus tasks such as aviation.ObjectiveOur goal was to assess the effects of tDCS applied during training with feedback on task performance, brain activity, and connectivity using func...

Objective: The objective of the current investigation was to examine associations between symptomatic COVID-19 history, neurocognitive function, and psychiatric symptoms using cognitive task performance, functional brain imaging, and a prospective population survey. Methods: Study 1 was a laboratory study conducted between 3 May 2022 and 16 Nov...

Clinical myoelectric prostheses lack the sensory feedback and sufficient dexterity required to complete activities of daily living efficiently and accurately. Providing haptic feedback of relevant environmental cues to the user or imbuing the prosthesis with autonomous control authority have been separately shown to improve prosthesis utility. Few...

One of the fundamental principles of neuroergonomics is that human cognition is profoundly shaped by the environment in which it operates. In the modern world, this environment can often be highly artificial, noisy, barren, and intentionally distracting. On the other hand, natural environments compare favorably as they may offer not only an appreci...

Clinical myoelectric prostheses lack the sensory feedback and sufficient dexterity required to complete activities of daily living efficiently and accurately. Providing haptic feedback of relevant environmental cues to the user or imbuing the prosthesis with autonomous control authority have been separately shown to improve prosthesis utility. Few...

Reconstructing perceived images from human brain activity monitored by functional magnetic resonance imaging (fMRI) is hard, especially for natural images. Existing methods often result in blurry and unintelligible reconstructions with low fidelity. In this study, we present a novel approach for enhanced image reconstruction, in which existing meth...

Reconstructing perceived images from human brain activity monitored by functional magnetic resonance imaging (fMRI) is hard, especially for natural images. Existing methods often result in blurry and unintelligible reconstructions with low fidelity. In this study, we present a novel approach for enhanced image reconstruction, in which existing meth...

The medial prefrontal cortex (MPFC) plays an important role in representing semantic self-knowledge. Studies comparing semantic self-judgments with judgments of close others suggest that interpersonal closeness may influence the degree to which the MPFC differentiates self and other. We used optical neuroimaging to examine if support for competence...

Background Vaccine hesitancy and inconsistent mitigation behavior performance have been significant challenges throughout the COVID-19 pandemic. In Canada, despite relatively high vaccine availability and uptake, willingness to accept booster shots and maintain mitigation behaviors in the post-acute phase of COVID-19 remain uncertain. The aim of th...

Background In concussion, functional near infrared spectroscopy (fNIRS) has been shown to detect differences in cortical oxygenation during neurocognitive testing, with concussed adults manifesting less task-based cortical activation compared to controls. In addition, fNIRS has identified significantly reduced interhemispheric coherence in adult co...

Adaptive interpersonal functioning relies on the effectiveness of behavioral and neural systems involved in cognitive control. Whether different subcomponents of cognitive control and their neural representations are associated with distinctive interpersonal dispositions has yet to be determined. The present study investigated the relationships bet...

Hemorrhage is a common consequence of traumatic brain injury and can be detected by near-infrared spectroscopy (NIRS)-based noninvasive sensors over scalp. In this study, our aim was to investigate NIRS measurements comprehensively using both phantoms and simulated head models of different age groups from infant to adult with intracranial hematoma...

Statement of Purpose Concussed adolescents frequently experience neurocognitive deficits even after symptom resolution. Measurement of cognitive deficits can be obtained using functional near-infrared spectroscopy (fNIRS), a portable, non-invasive imaging technology that measures prefrontal cortical (PFC) activity. The goal of this exploratory stud...

Statement of Purpose Adolescents frequently experience neurocognitive deficits post-concussion, potentially affecting driving performance. Measurement of cognitive workload and deficits can be obtained using functional near-infrared spectroscopy (fNIRS), a portable, non-invasive imaging technology that measures prefrontal cortical (PFC) activity. T...

Objective Women’s experiences of sexual violence can be not only psychologically and physically traumatizing but may also have lasting effects on brain functions, including cognitive control relating to the inhibition and processing of emotion. Thus, the purpose of this pilot study is to explore underlying neural correlates of sexual violence’s imp...

Background The sense of ‘loss of control’ (LOC), or a feeling of being unable to stop eating or control what or how much one is eating, is the most salient aspect of binge eating. However, the neural alterations that may contribute to this experience and eating behavior remain poorly understood. Methods We used functional near-infrared spectroscop...

To understand how to improve interactions with dog-like robots, we evaluated the importance of “dog-like” framing and physical appearance on interaction, hypothesizing multiple interactive benefits of each. We assessed whether framing Aibo as a puppy (i.e., in need of development) versus simply a robot would result in more positive responses and in...

Latent Dirichlet Allocation (LDA) and Sentiment Analysis have become prominent tools in natural language processing applications for both research and industry. While LDA is a generative probabilistic modeling methodology that is widely used in Topic Modeling to extract underlying themes and topics from a collection of words, Sentiment Analysis is...

Video games provide a high-octane competitive sports platform where players with diverse skills engage in tasks that require precise control of cognitive skills and emotional responses. Electrodermal activity (EDA) is a portable, non-invasive, and wearable physiological activity sensing modality that captures correlates of emotional responses. In t...

Much work has been done to engineer robots’ mechanical capabilities to best suit the general demands of their users and tasks. However, minimal research has addressed the impact of individual differences on perceptions of robot trustworthiness. These conclusions can provide guidance to optimize adaptive robotic systems in education, healthcare, and...

Traditionally, recording from and stimulating the brain with high spatial and temporal resolution required invasive means. However, recently, the technical capabilities of less invasive and non-invasive neuro-interfacing technology have been dramatically improving, and laboratories and funders aim to further improve these capabilities. These techno...

Neurotechnologies combine neuroscience and engineering to create tools for studying, repairing, and enhancing brain function. Traditionally, researchers have used neurotechnologies, such as Brain-Computer Interfaces (BCIs), as assistive devices, for example to allow locked-in patients to communicate. In the last few decades, non-invasive brain imag...

The brain undergoes dramatic changes over the course of the adolescent years, and these developmental changes are implicated in the emergence of disorders that involve negative emotionality. Late adolescence might be the window within which brain networks manifest vulnerabilities to depressive and anxiety symptomology; particularly within the prefr...

A within-subjects experimental design examined differences in functional near-infrared spectroscopy (fNIRS) assessment of prefrontal cortex (PFC) activation with two virtual reality (VR) drawing conditions (rote tracing and creative self-expression) with and without a fragrance stimulus. Participants were healthy adults and included 18 women, 6 men...

Until recently, neural assessments of gross motor coordination could not reliably handle active tasks, particularly in realistic environments, and offered a narrow understanding of motor-cognition. By applying a comprehensive neuroergonomic approach using optical mobile neuroimaging, we demonstrated the broader capability for ecologically relevant...

Several adolescent health behaviours have been hypothesized to improve academic performance via their beneficial impact on cognitive control and functional aspects of the prefrontal cortex (PFC). The primary objective of this study is to examine the association between lifestyle behaviours and academic performance in a sample of adolescents, and to...

Brain computer interface (BCI) technology is an alternate communication option for individuals with neuromuscular impairments. There are several challenges to optimal BCI use including positioning of the screen, ease of use, independence in access, and calibration. Our study is directed at the development of a practical, accessible, at-home use BCI...

The performance of a team is tightly connected to how well its members communicate and collaborate while working towards shared objectives, a process known as group cognition. In competitive team sports, strategic and efficient coordination between team members often makes the difference between success and failure. Professional e-sport gaming, in...

Brain Computer Interface (BCI) systems potentially provide those with disabilities an alternative means to communicate and control their environment, increasing independence and quality of life. The goal of our study was to examine the effect of disease progression on the efficiency of communication using a P300 BCI speller. To address this, BCI da...

The use of mobile, low-cost, and wearable sensors to measure physiological activity, continuously and non-intrusively during everyday tasks has the potential to improve our understanding of human perception, cognition, and behavior at large. One applied field with the practical use of such expansive assessment is consumer neuroergonomics. In this s...

Mental workload assessment is a core element of designing complex high-precision human machine interfaces with industrial and medical applications, from aviation to robotic neurosurgery. High accuracy and continuous mental state decoding play an essential role for keeping the operator’s mental workload on a moderate level to prevent cognitive tunne...

Visual messaging has been widely researched in psychology and communications specifically within the area of advertising [2, 3]. Such messaging research seeks to identify the characteristics and variables within an advertisement that contribute most to its effectiveness [4]. The present study aimed to investigate the relationship between the presen...

Objective This review highlights the scope and significance of the coronavirus disease 2019 (COVID-19) pandemic with a focus on biobehavioral aspects and critical avenues for research. Methods A narrative review of the published research literature was undertaken, highlighting major empirical findings emerging during the first and second waves o...

Hyperscanning studies using functional Near-Infrared Spectroscopy (fNIRS) have been performed to understand the neural mechanisms underlying human-human interactions. In this study, we propose a novel methodological approach that is developed for fNIRS multi-brain analysis. Our method uses support vector regression (SVR) to predict one brain activi...

Evaluations of haptic feedback in myoelectric prostheses are generally limited to task performance outcomes, which while necessary, fail to capture the mental effort of the user operating the prosthesis. Cognitive load is usually investigated with reaction time metrics and secondary task accuracy, which are indirect, and may not capture the time-va...

The dorsolateral prefrontal cortex (dlPFC) and dorsomedial prefrontal cortex (dmPFC) are important nodes for self-control and decision-making, but through separable processes (cognitive control versus evaluative processing). This study aimed to examine the effects of excitatory brain stimulation (intermittent theta-burst stimulation; iTBS) targetin...

[This corrects the article DOI: 10.1117/1.NPh.8.1.012101.].

Persons with opioid use disorder (OUD) often experience anhedonia and demoralization, yet there is relatively little research on the pathophysiology of anhedonia and demoralization in OUD treatment and recovery. In the current study, persons maintained on methadone (N = 29) underwent a natural reward-cue paradigm during functional near-infrared spe...

The application of functional near-infrared spectroscopy (fNIRS) in the neurosciences has been expanding over the last 40 years. Today, it is addressing a wide range of applications within different populations and utilizes a great variety of experimental paradigms. With the rapid growth and the diversification of research methods, some inconsisten...

Robots are a human-like product. To address the challenge of measuring responses to an object perceived as part product – part entity, researchers have evaluated robot appearance based on human-likeness. This review presents research that views human-likeness through the lens of the psychological construct of anthropomorphism. This review also brie...

The field of enhancing skill acquisition, particularly in professions necessitating the mastery of a complex combination of physical and mental abilities, is rapidly progressing and amenable to novel training protocols involving both neuroimaging and neurostimulation. Aircraft piloting in particular is an ideal medium for testing new training proto...

This book offers broad overview of the field of cognitive engineering and neuroergonomics, covering emerging practices and future trends toward the harmonious integration of human operators and computer systems. It presents novel theoretical findings on mental workload and stress, activity theory, human reliability, error and risk, and a wealth of...

The dorsolateral prefrontal cortex (dlPFC) and dorsomedial prefrontal cortex (dmPFC) are important nodes for self-control and decision-making, but through separable processes (cognitive control versus evaluative processing). This study aimed to examine the effects of excitatory brain stimulation (intermittent theta-burst stimulation; iTBS) targetin...

Background: Several adolescent health behaviors have been hypothesized to improve academic performance via their beneficial impact on cognitive control and functional aspects of the prefrontal cortex (PFC). Specifically, exercise, restorative sleep, and proper diet are thought to improve PFC function, while substance abuse is thought to reduce it....

Food waste is a global crisis that paradoxically exists alongside food scarcity. A promising solution to these connected problems of food insecurity and food waste is upcycled foods. Upcycled foods are made from ingredients that are usable but generally discarded. While upcycled foods can help reduce food waste, little is known about the best marke...

Research on food waste reduction suggests that solutions aimed at reducing waste early in the consumption cycle are the most impactful. Based on this premise, food research labs and food manufacturers have started creating and selling foods made from food ingredients that are generally discarded. Such foods, termed upcycled foods, are safe for huma...

Understanding how we make decisions has far-reaching practical implications from medicine to marketing as it is a fundamental cognitive construct intertwined in our everyday lives. Even though there is research on the influence of messaging on decision-making behavior, the effects from a psychophysiological perspective have not yet been fully under...

Understanding the impact of messaging on choice from a neural perspective is a major research interest in the fields of cognitive science, psychology, business and communications. In this study, we investigated the impact of a pro-environmental audiovisual message on consumer electricity supply preference as well as the differences in consumer hemo...

Neuroergonomics is an emerging field that investigates the human brain about behavioral performance in natural environments and everyday settings. This study investigated the body and brain activity correlates of a typical daily activity, hot beverage preparation, and consumption in a realistic office environment where participants performed natura...

For over two centuries, the wheelchair has been one of the most common assistive devices for individuals with locomotor impairments without many modifications. Wheelchair control is a complex motor task that increases both the physical and cognitive workload. New wheelchair interfaces, including Power Assisted devices, can further augment users by...

Background: Transcranial direct current stimulation (tDCS) has been shown to be an inexpensive, safe, and effective way of augmenting a variety of cognitive abilities. Relatively recent advances in neuroimaging technology have provided the ability to measure brain activity concurrently during active brain stimulation rather than after stimulation....

Coffee and tea are two of the most popular beverages in the world and have been consumed for more than a thousand years. They have become an integral part of the day for many consumers and may aid not only increased social interactions but also productivity. However, there is no conclusive evidence of their comparative effect on cognitive ability....

OBJECTIVES This document aims at providing an overview of the existing and developing standards in the field of neurotechnologies for brain‐machine interfacing. It is mainly focused on systems that provide a closed‐loop interaction with artificial devices based on information extracted from measures of the activity in the nervous systems. In additi...

Human facial expressions are regarded as a vital indicator of one's emotion and intention, and even reveal the state of health and wellbeing. Emotional states have been associated with information processing within and between subcortical and cortical areas of the brain, including the amygdala and prefrontal cortex. In this study, we evaluated the...

The wheelchair is a key invention that provides individuals with limitations in mobility increased independence and participation in society. However, wheelchair control is a complicated motor task that increases physical and mental workload. New wheelchair interfaces, including power-assisted devices can further enable users by reducing the requir...

The classification of workload memory tasks based on fNIRS and EEG signals requires solving high-dimensional pattern classification problems with a relatively small number of training patterns. In the use of conventional machine learning algorithms, feature selection is a fundamental difficulty given the large number of possible features and the sm...

Electrodermal activity (EDA) is a portable, non-invasive and wearable sensor that measures skin electrical properties to track correlates of autonomic nervous system activity. Although EDA utilization is sparse compared to some other biomedical signals in ambulatory settings, it can be a potentially helpful adjunct tool in neuroergonomics studies a...