Filter by type:

Sort by year:

The Quest for Functional Biomarkers in the Prefrontal Cortex Using Functional Near-Infrared Spectroscopy (fNIRS)

Book Chapter
Hadis Dashtestani, Rachel Zaragoza, Riley Kermanian, Emma Condy, Afrouz Anderson, Fatima Chowdhry, Nader Shahni Karamzadeh, Helga Miguel, Siamak Aram, Amir Gandjbakhche
Neurophotonics and Biomedical Spectroscopy. Elsevier, 2019. 123-136.
Publication year: 2019
The prefrontal cortex (PFC) has been recognized as one of the most crucial brain regions responsible for cognitive control, thoughts, and actions. Advanced functional imaging has provided tools needed for the sensitive assessment of functional brain activities and also functional abnormalities in various brain regions. Functional near-infrared spectroscopy (fNIRS) is a highly promising neuroimaging modality that provides an efficient way to continuously monitor changes in blood oxygenation in the brain. Functional biomarkers validated and measured from fNIRS data have provided reliable and predictive information on various brain functional disorders. However, selecting optimum biomarkers from a set of hemodynamic features can be extremely challenging. Here, we focus on functional biomarkers driven from fNIRS data and advanced multivariate analysis used to extract those biomarkers. We introduce …

Exploring the role of task performance and learning style on prefrontal hemodynamics during a working memory task

Journal paper
Afrouz A Anderson, Kian Parsa, Sydney Geiger, Rachel Zaragoza, Riley Kermanian, Helga Miguel, Hadis Dashtestani, Fatima A Chowdhry, Elizabeth Smith, Siamak Aram, Amir H Gandjbakhche
PloS one 13.6 (2018): e0198257.
Publication year: 2018

Existing literature outlines the quality and location of activation in the prefrontal cortex (PFC) during working memory (WM) tasks. However, the effects of individual differences on the underlying neural process of WM tasks are still unclear. In this functional near infrared spectroscopy study, we administered a visual and auditory n-back task to examine activation in the PFC while considering the influences of task performance, and preferred learning strategy (VARK score). While controlling for age, results indicated that high performance (HP) subjects (accuracy > 90%) showed task dependent lower activation compared to normal performance subjects in PFC region Specifically HP groups showed lower activation in left dorsolateral PFC (DLPFC) region during performance of auditory task whereas during visual task they showed lower activation in the right DLPFC. After accounting for learning style, we found a correlation between visual and aural VARK score and level of activation in the PFC. Subjects with higher visual VARK scores displayed lower activation during auditory task in left DLPFC, while those with higher visual scores exhibited higher activation during visual task in bilateral DLPFC. During performance of auditory task, HP subjects had higher visual VARK scores compared to NP subjects indicating an effect of learning style on the task performance and activation. The results of this study show that learning style and task performance can influence PFC activation, with applications toward neurological implications of learning style and populations with deficits in auditory or visual processing.

Implantable Medical Devices; Networking Security Survey.

Journal paper
Journal of Internet Services and Information Security., 6(3), 40-60.
Publication year: 2016

The industry of implantable medical devices (IMDs) is constantly evolving, which is dictated by the pressing need to comprehensively address new challenges in the healthcare field. Accordingly, IMDs are becoming more and more sophisticated. Not long ago, the range of IMDs’ technical capacities was expanded, making it possible to establish Internet connection in case of necessity and/or emergency situation for the patient. At the same time, while the web connectivity of today’s implantable devices is rather advanced, the issue of equipping the IMDs with sufficiently strong security system remains unresolved. In fact, IMDs have relatively weak security mechanisms which render them vulnerable to cyber-attacks that compromise the quality of IMDs’ functionalities. This study revolves around the security deficiencies inherent to three types of sensor-based medical devices; biosensors, insulin pump systems and implantable cardioverter defibrillators. Manufacturers of these devices should take into consideration that security and effectiveness of the functionality of implants is highly dependent on the design. In this paper, we present a comprehensive study of IMDs’ architecture and specifically investigate their vulnerabilities at networking interface.

Conserving Energy Through Neural Prediction of Sensed Data

Journal paper
Siamak Aram, Ikramullah Khosa, Eros Gian Alessandro Pasero
JOURNAL OF WIRELESS MOBILE NETWORKS, UBIQUITOUS COMPUTING AND DEPENDABLE APPLICATIONS
Publication year: 2015

The constraint of energy consumption is a serious problem in wireless sensor networks (WSNs). In this regard, many solutions for this problem have been proposed in recent years. In one line of research, scholars suggest data driven approaches to help conserve energy by reducing the amount of required communication in the network. This paper is an attempt in this area and proposes that sensors be powered on intermittently. A neural network will then simulate sensors’ data during their idle periods. The success of this method relies heavily on a high correlation between the points making a time series of sensed data. To demonstrate the effectiveness of the idea, we conduct a number of experiments. In doing so, we train a NAR network against various datasets of sensed humidity and temperature in different environments. By testing on actual data, it is shown that the predictions by the device greatly obviate the need for sensed data during sensors’ idle periods and save over 65 percent of energy.

Mobile environmental sensing using smartphones

Book Chapter
Siamak Aram, Amedeo Troiano, Francesco Rugiano, Eros Pasero
Measurement Instrumentation, and Sensors Handbook Second Edition: Electromagnetic Optical Radiation Chemical, and Biomedical Measurement (2014).
Publication year: 2014

Improving lifetime in wireless sensor networks using neural data prediction

Conference paper
Siamak Aram, Luca Mesin, Eros Pasero
Computer Applications & Research (WSCAR), 2014 World Symposium on (pp. 1-3). IEEE.
Publication year: 2014

The acceptance of wireless sensor networks (WSN) has increased greatly due to their comprehensive capabilities. Since WSNs are generally battery-powered networks, reducing energy consumption is critical to improve their lifetime and, in turn, their performance and reliability. Recently, smart processing, especially neural networks, has been employed to efficiently manage the power consumed by Wireless Sensor Networks (WSN). Data driven approaches and, in particular, data reduction schemes can reduce the energy spent for communication by judicious selection of the time in which specific sensors of the network are interrogated. In this paper, a multi-layer perceptron (MLP) is used to decide on the data samples required. To justify the usefulness of our idea, we conduct an experiment for effective monitoring of environmental conditions. Results show that our method reduces the number of required samples …

A neural data-driven approach to increase Wireless Sensor Networks' lifetime

Conference paper
Luca Mesin, Siamak Aram, Eros Pasero
Computer Applications & Research (WSCAR), 2014 World Symposium on. IEEE, 2014.
Publication year: 2014

Wireless Sensor Networks (WSN) play an important role in functioning of various applications. However, technical difficulties, like shortages in power supply, may eventually narrow down WSN’s application range. Minimization of power supply thus can be an adequate mean of prolonging their lifetime. Most of the components of a sensor, including its radio, can be turned off most of the time without influencing the network functionalities it is responsible for. Computational intelligence and, in particular, data prediction methods, may ensure effective operation of the network by the selection of essential samples. In this paper, we apply a multi-layer perception to select the required samples from simulated and experimental meteorological data. The results show that it leads to a considerable reduction of the number of samples and consequently of the power consumption, still preserving the information content.

A neural data-driven algorithm for smart sampling in wireless sensor networks

Journal paper
Luca Mesin, Siamak Aram, Eros Pasero
EURASIP Journal on Wireless Communications and Networking 2014.1 (2014): 23.
Publication year: 2014

Wireless sensor networks (WSN) take on an invaluable technology in many applications. Their prevalence, however, is threatened by a number of technical difficulties, especially the shortage of energy in sensors. To mitigate this problem, we propose a smart reduction in data communication by sensors. Indeed, in case we have a solution to this end, the components of a sensor, including its radio, can be turned off most of the time without noticeable influence on network operation. Thus, reducing the acquired data, the sensors can be idle for longer and power can be saved. The main idea in devising such a solution is to minimize the correlation between the data communicated. In order to reduce the measurements, we present a data prediction method based on neural networks which performs an adaptive, data-driven, and non-uniform sampling. Evidently, the amount of possible reduction in required samples is bounded by the extent to which the sensed data is stationary. The proposed method is validated on simulated and experimental data. The results show that it leads to a considerable reduction of the number of samples required (and hence also a power saving) while still providing a good approximation of the data.

Low power and bluetooth-based wireless sensor network for environmental sensing using smartphones

Conference paper
Siamak Aram, Amedeo Troiano, Francesco Rugiano, Eros Pasero
IFIP International Conference on Artificial Intelligence Applications and Innovations (pp. 332-340). Springer, Berlin, Heidelberg.
Publication year: 2012

Current research and improvements in the field of wireless sensor networks are focused on decreasing the power consumption and miniaturization, improved smartness and better wearability of the sensor, and especially with their capability for environmental sensing. Today, the survival of these kinds of networks is a critical issue especially in order to keep environmental information updated. This paper presents, an improvement of the environmental sensing acquisition system shown in [1], by applying more sensors to gather data. It was found a novel method of reading sensor data using smartphones and also the structure of sensors themselves helps to decrease the power consumption of the network.

Environment sensing using smartphone

Conference paper
Siamak Aram, Amedeo Troiano, Eros Pasero
Sensors Applications Symposium (SAS), 2012 IEEE. IEEE, 2012.
Publication year: 2012

Mobile devices (in particular smartphones and tablets) can be used to monitor quality of life parameters. Today mobile devices use embedded sensors such as accelerometers, compasses, GPSs, microphones, and cameras without considering, for example, the air quality or the pollutants of the environment. This paper presents the possibility to use the smartphones capabilities to gather data from other phones or sensors. Nowadays, monitoring climate condition’s parameters such as temperature and humidity is a prominent factor to control the changes of the environmental condition of living or working places for the human being. This point can be obtained by using distributed devices in different environments that containing high-resolution sensors and a wireless transmission apparatus for transferring data to smartphones. The Bluetooth was chosen as a transmission tool since it is embedded in all smartphones …