Tuesday, August 21, 2012

Give me a Voice. Brain Science & Speech

Technion & UCLA researchers have identified a structured code for representing speech movements by neurons in the human brain. The researchers were able to directly decode vowels from neural activity - a finding which could allow individuals who are paralyzed to "speak" to people around them through a brain-computer interface

In the photo: the two language areas where cell reactions during speech were researched. The graphs present a selective code for vowels in an area in the frontal lobe and a non-selective code in an area in the temporal lobe (each color represents a neuron). The image highlights the brain areas where neurons with a structured code for speech generation were found. In the frontal region neurons were highly vowel-selective while in the temporal region (on the right) the code was broad and non-selective.

Technion and UCLA researchers have directly decoded vowels from the neural activity which leads to their articulation - a finding which could allow individuals who are paralyzed to "speak" to the people around them through a direct brain-computer interface. 

Prof. Shy Shoham and Dr. Ariel Tankus of the Technion Department of Biomedical Engineering, together with Prof. Itzhak Fried of the University of California Los Angeles (UCLA) and the Tel Aviv University and Medical Center departments of Neurosurgery, describe the way in which neurons in different areas of the human brain encode different speech segments (vowels) during their articulation in the scientific journal Nature Communications

The discovery will indirectly enable scientists to decode the content of the subjects' speech based on brain activity alone. One of the possible applications of speech decoding from brain activity is the creation of a brain-computer interface that can restore speech faculties in paralyzed individuals who have lost them.

"There are diseases in which the patient's entire body is paralyzed, he is effectively 'locked in' (locked-in syndrome) and is unable to communicate with the environment, but his mind still functions", explains Prof. Shoham, Head of the Neural Interface Engineering Laboratory in the Technion Department of Biomedical Engineering. "Our long term goal is to restore these patients' ability to speak using systems that will include implanting electrodes in their brains, decoding the neural activity that encodes speech, and sounding artificial speech sounds. For this purpose, we wanted to first understand how the information about the articulated syllable is encoded in the electrical activity of an individual brain neuron and of a neuron population. In our experiments we identified cell populations that distinctly participate in the representation. For example, cells we registered in an area in the medial frontal lobe that includes the anterior cingulate cortex, surprised us in the manner in which they 'sharply' represented certain vowels but not others, even though the area is not necessarily known as having a major role in the speech generation process".

The experiments were conducted in the UCLA Medical Center with the participation of epilepsy patients, in whose brain Prof. Fried and his team implanted depth electrodes. The objective of the implant is to locate the epileptic focus, which is the area in the brain where epileptic seizures begin. After the surgery, the patients were hospitalized for a week or two with the electrodes in their brain, and waited for the occurrence of spontaneous seizures. 

During that time, Dr. Tankus, who was a post-doctoral fellow at UCLA and is now a researcher at the Technion, conducted experiments in which he asked patients to articulate vowels as well as syllables comprising a consonant and a vowel, and recorded the resulting neuronal activity in their brain. 

The researchers discovered two neuron populations that encode the information about the vowel articulated in an entirely different way. In the first population, identified in the medial frontal lobe, each neuron encodes only one or two vowels by changing its firing rate, but does not change its activity when other vowels are articulated. However, in the second population, located in the superior temporal gyrus, each neuron reacts to all vowels tested, but the cell's reaction strength changes gradually between vowels. 

Moreover, the researchers were able to deduce a mathematical arrangement of the manner in which the vowels are represented in the brain, showing it to match the phonetic vowel trapezoid, which is built according to the location of the highest point of the tongue during articulation. Thus, the researchers succeeded in connecting the brain representation with the anatomy and physiology of vowel articulation.

Understanding brain representation of speech generation constitutes a significant step on the road to decoding cellular activity using a computer, as Dr. Tankus explains: "We have developed a new algorithm that improves the ability to identify from brain activity which syllable was articulated, and this algorithm has allowed us to obtain very high identification rates. Based on the present findings, we are currently conducting experiments toward the creation of a brain-machine interface that will restore  speech faculties".

Sunday, August 19, 2012

A new year - and the robots are ready to party!

The Jewish year of 

Geeks are boring? NO way. Nobel Laureates live in ivory towers? University presidents are inaccessible? Perhaps you should ask Technion President Prof. Peretz Lavie for some Hip Hop.

Join the entire Technion family and the world community of lovers of education, science and technology with some of the hottest robots from Technion - Israel Institute of Technology as they strut their stuff to a hip-hop cover of the traditional Jewish song, Shana Tova, or happy new year. Save it and share it with children and loved ones everywhere as a special new year's greeting!

Bonne année, З Новим роком, نیا سال مبارک ہو, Yeni iliniz mübarək, Buon anno, Hamingjusamur Nýtt Ár, Athbhliain faoi mhaise daoibh, Gëzuar Vitin e Ri, Head uut aastat, Bonan Novjaron, Честита Нова Година, З Новым годам, শুভ নববর্ষ, გილოცავთ
 ახალ წელს, હેપ્પી ન્યુ યર, Feliz ano, Glückliches neues Jahr,
Godt Nytår. Gelukkig Nieuwjaar, नया साल मुबारक, Blwyddyn Newydd Dda, Chúc mừng năm mới, புத்தாண்டு, Yeni Yılınız Kutlu Olsun, హ్యాపీ న్యూ ఇయర్, Ευτυχισμένο το Νέο Έτος, מזל ניו יאָר, 明けましておめでとうございます, Laimīgu Jauno gadu, Felix Novus Annus, Naujųjų Metų, Selamat Tahun Baru, Godt Nyttår, Heri ya Mwaka Mpya, 新年好, Srečno novo leto, Šťastný Nový Rok, Feliz Año Nuevo, Срећна Нова Година, سنة جديدة سعيدة, Manigong Bagong Taon, Onnellista uutta vuotta, سال نو مبارک, Šťastný Nový Rok, Bonne année, 새해 복 많이 받으세요, Feliç Any Nou, La mulți ani, С Новым годом, Gott Nytt År, สวัสดีปีใหม่!!!!!!!!!!!

Sunday, August 12, 2012

An optical spin - the nanoscience of electrons

Prof. Erez Hasman, Technion.

The spin Hall effect - the impact of the intrinsic spin on the particle trajectory, which produces transverse deflection of the particle - is a central tenet in the field of spintronics regarding particles of electrons. Now, its optical equivalent has been observed.

The Magnus effect is seen in a wide range of systems. For example, it describes the sideways force applied to a spinning ball as it travels through the air explains Prof. Erez Hasman, head of the Micro- and Nanooptics Laboratory and an avid tennis player.

Light waves, comprising mass-less particles called photons, also demonstrate spin. Light's spin is determined by its polarization: whether the wave vibration rotates in one direction or the opposite as it travels. Hasman, together with his PhD student Avi Niv, Dr Vladimir Kleiner - a senior scientist in the lab - and Ukrainian visiting scientist Dr Konstantin Bliokh, were the first to observe the effect of spin on the trajectories of polarized light beams.

The researchers launched a laser beam at a sliding angle to the internal surface of a glass cylinder. Once inside the cylinder the beam traveled in a helical trajectory along the glass-air interface, and was collected and analyzed at the far end using polarization optics and a camera. They observed a transverse spin-dependent deflection of the optical beam. These results have promising applications in nano-optics leading to much faster and more accurate computational data processing.

Physics Prof. Mordechai (Moti) Segev, a world leader in the area of Nonlinear Optics, comments, "Nanophotonics is a field where light is manipulated and controlled on a scale that is smaller than the optical wavelength. Erez Hasman has written a series of important papers in this area, leading to a new branch in optics - spinoptics. His discoveries offer an unprecedented ability to control light and its polarization state in nanometer-scale optical devices, thereby facilitating a variety of applications related to nanophotonics."

Applied to other areas Hasman says, "There are a number of systems where the spin of a particle couples with its trajectory in high-energy and condensed matter physics. The math is the same in all cases, but experimentally it's hard to understand what's going on. Our experimental system offers a new way to get at some of these fundamental questions clearly and precisely."

What is Photonics?

Photonics is the science of generating, controlling, and detecting photons. Photonics researchers investigate the emission, transmission, amplification, detection, and modulation of light. Applications include laser manufacturing, biological and chemical sensing, medical diagnostics and therapy, display technology, and optical computing.

Spinoptics: The Magnus effect for light, also called the optical spin Hall effect, causes the light to deflect due to the interaction between the intrinsic spin of the photons and the shape of the light's trajectory.

Can you see Mars? Technion Science.

Mars is live - thanks to the Lempel Ziv algorithm for lossless data compression developed at Technion.


"The video compression on Curiosity rover is indeed a version of the LOCO system that was developed by Marcelo Weinberger  and Gadiel Seroussi -both are Technion graduates," says Technion Distinguishe Prof. Jacob Ziv

Images sent back to Earth from the Curiosity rover are using a version of the LOCO system for video compression developed by Technion alumni, Drs Marcelo Weinberger and Gadiel Seroussi. Weinberger and Seroussi’s doctoral advisors were Profs. Abraham Lempel and Jacob Ziv, developers of the Lempel-Ziv coding algorithm – a world standard for compressed information transmission.
NASA's groundbreaking mission seeks to determine whether Mars is or has ever been capable of supporting life and to assess the planet's habitability for future human missions. 

To maximize the number of images acquired during the mission, virtually all image data will be compressed by the rover CPU (using either lossy or lossless compression) prior to placement into the telemetry stream. To perform this task the rovers will utilize a software implementation of the JPL-developed ICER wavelet-based image compressor [Kiely and Klimesh, 2003], capable of providing lossy and lossless compression. In cases where lossless compression is desired and speed is particularly important, compression will be performed (in software) by a modified version of the low-complexity (LOCO) lossless image compression algorithm [Klimesh et al., 2001; Weinberger et al., 1996]. The MER mission is utilizing state of the art image compression technology by flying compressors that deliver compression effectiveness comparable to that achieved by the JPEG- 2000 image compression standard [Adams, 2001], but with lower computational complexity [Kiely and Klimesh, 2003].

Did you know? 
Mars's average distance from the Sun is roughly 230 million km (1.5 AU, or 143 million miles) and its orbital period is 687 (Earth) days as depicted by the red trail, with Earth's orbit shown in blue.(Animation)

Tuesday, August 7, 2012

The Technion Birthright

Birthright Bar Mitzvah Celebrated in Haifa
Date: 06/08/2012
Source: Technion FOCUS.
Taglit - also known as the Birthright Israel program - is celebrating its Bar Mitzvah (13th anniversary). To mark the occasion, more than 500 current participants came to Technion where they heard two lectures from dynamic faculty who are both immigrants to Israel: Dr. Josue Sznitman of Technion's Faculty of Biomedical Engineering and Prof. Mark Talesnick of the Faculty of Civil and Environmental Engineering.
Talesnick spoke about Technion's Engineers Without Borders outreach program that he initiated and Sznitman discussed his cutting-edge research.
Albert Sweet, of Los Angeles, CA, has been one of Technion's generous supporters for many years as well as a supporter of the Birthright program. Through an initiative he started a few years ago Birthright participants are brought to Technion to get a sense of Technion's contribution to Israel's becoming a high-technology superpower and a critical player in helping drive Israel's economy, medical research and security.