Friday, September 26, 2014

Two post docs in Philly

Postdoctoral Fellowship in Noninvasive Brain Stimulation in Neurorehabilitation and Aphasia 
Laboratory for Cognition and Neural Stimulation (LCNS), University of Pennsylvania

A postdoctoral fellowship is available in the Laboratory for Cognition and Neural Stimulation (LCNS) under the direction of Roy Hamilton, MD, MS, a behavioral neurologist at the University of Pennsylvania (Penn). The central thrust of work in the LCNS is to use electrical and magnetic noninvasive brain stimulation to explore the characteristics and limits of functional plasticity in the intact and injured adult human brain. The principle NIH-grant funded project related to the postdoctoral position involves behavioral, neuropsychological, and neurostimulation (rTMS) approaches in patients with aphasia. Additional available projects in the LCNS involve other forms of neurostimulation, including tDCS and HD-tDCS, as well as neuroimaging (fMRI, fNIRS) approaches. The ideal candidate must have experience in one or more of the following areas: behavioral studies in brain-injured patient populations, studies involving measures of human neurophysiology (EEG, ERP), functional or anatomical imaging techniques, advanced statistics, or noninvasive brain stimulation techniques. A track record of prior academic authorship is strongly encouraged. Moreover, an ideal candidate must be able to work independently and proactively propose and test new ideas that are relevant to his or her projects. Good oral and written communication skills are expected. The fellow will train with Dr. Hamilton as a primary mentor, but will also be expected to interact and collaborate with a network of outstanding peers and secondary mentors in the Center for Cognitive Neuroscience (CCN) and the Department of Neurology at Penn. Eligible candidates must hold a PhD or comparable degree. While applicants with a wide range of training backgrounds will be considered, a doctoral degree in psychology, cognitive neuroscience, biomedical engineering, or neurorehabilitation will be considered a strong asset to the position. The position is a full-time appointment initially for 12 months, with the possibility of renewing for additional years, contingent upon funding. Pay will follow the NIH payscale. The anticipated start date would be 1/1/15, but there is room for negotiation. Women and under-represented groups are encouraged to apply.

For inquiries please contact Roy Hamilton, MD, MS at roy.hamilton@uphs.upenn.edu, (215) 779-1603.

Post-Doctoral Fellowships in Translational Neuroscience and Neurorehabilitation
Three year NIH-funded fellowships are available at the Moss Rehabilitation Research Institute (MRRI), in collaboration with the University of Pennsylvania (Penn), for research training in cognitive and motor neuroscience and neurorehabilitation. This program is designed specifically to prepare young investigators to adapt emerging theoretical advances to the development of rehabilitation treatments. To that end, we invite applications from (1) individuals with relevant basic science training who wish to learn to apply basic science principles to the study and treatment of neurological deficits and (2) individuals with relevant clinical training who wish to learn cutting-edge neuroscience and neurorehabilitation research methods. Fellows will train with a primary mentor at either MRRI or Penn and will interact with peers and mentors with diverse clinical and experimental backgrounds. Applications will be reviewed on a rolling basis until all of the available positions are filled.
Women and minorities are strongly encouraged to apply.
Applicants must be citizens or non-citizen nationals of the United States or have been lawfully admitted for permanent residence. Both MRRI and Penn are Equal Opportunity Employers and welcome and encourages all qualified candidates to apply including, but not limited to, minorities and individuals with disabilities. A complete list of available mentors and instructions for application are available at http://mrri.org/T32.html.
Applications should be submitted to Kevin Whelihan, Research Administrator,
 whelihak@einstein.edu ) and must include:
- current CV
- cover letter describing research interests and career goals. Given the translational focus of the training program, applicants should indicate a preferred primary mentor and, if possible, one or more secondary mentors who appear to offer the best fit in balancing basic and applied aspects of the candidate’s interests.
- 2-3 letters of reference

Professor or Reader in Human Neuroscience Royal Holloway, University of London - Department of Psychology

Full Time - permanent role
Professorial salary is in the range £60,791 to £112,365 per annum inclusive of London Allowance,dependent on assessment through the College Professorial Pay Banding Scheme.
Reader salary is in the range £49,462 to £56,975 per annum inclusive of London Allowance
Applications are invited for a permanent post at Professorial or Reader level in the Department of Psychology, Royal Holloway, University of London. 
We invite applicants with a PhD in Psychology or related discipline, who possess an outstanding international research profile in human neuroscience, both in terms of research publications and in gaining research funding, to join our internationally recognized academic team.  Successful applicants will be expected to have an established programme of research in the neuroscience of human behaviour that includes functional MRI. Experience of other MRI techniques (e.g. DTI and MRS) will be an advantage and ideally candidates will have expertise in MRI data acquisition as well as data analysis. It is envisaged that the appointee may take on a leadership role in our MRI unit and will contribute strongly to the strategic direction of neuroscience research in the Department. The successful candidate would contribute to the undergraduate and postgraduate student curriculum as well as contributing across a range of departmental activities.
We offer a dynamic and supportive environment, in an internationally recognized department that ranks among the best in the UK for research and teaching and has ambitious plans for development and growth. The Department has state-of-the-art facilities available for researchers including MRI, EEG, TMS, eye trackers, behavioural testing suites, social and infant observation labs. It also has strong links with clinical organisations, as well as government, industrial, and charity affiliations. The College was ranked 102 in the Times HE World University Rankings 2013-14 and is the leading university, in the UK, in terms of its “international outlook”. Information about our existing research groups and department structure can be found on our Departmental website: http://www.rhul.ac.uk/psychology
This is a full time and permanent post based in Egham, Surrey where the College is situated in a beautiful, leafy campus with excellent local schools and easy commuting distance to central London.  The start date for this post is flexible however we would expect that the appointee would take up the position in the first half of 2015.
Informal enquiries regarding this post can be directed to the Head of Department, Professor Patrick Leman (Patrick.Leman@royalholloway.ac.uk).
To view further details of this post and to apply please visit https://jobs.royalholloway.ac.ukThe RHUL Recruitment Team can be contacted with queries by email at: recruitment@rhul.ac.uk or via telephone on: +44 (0)1784 41 4241.
Please quote the reference: 0914-186
Closing Date:  Midnight 29th October 2014
Interview Date:  Likely to take place 13th November 2014 and candidate presentations are very likely to be on that date.  
The College is committed to equality and diversity, and encourages applications from all sections of the community.

Wednesday, September 24, 2014

Mirror neurons do not resonate with actions: two pieces of single-unit evidence

Gergley Csibra (2007) noticed a fundamental flaw in the logic of the mirror neuron theory of action understanding:
[there is] a tension between two conflicting claims about action mirroring implied by the direct-matching hypothesis: the claim that action mirroring reflects low-level resonance mechanisms, and the claim that it reflects high-level action understanding. The tension arises from the fact that the more it seems that mirroring is nothing else but faithful duplication of observed actions, the less evidence it provides for action understanding; and the more mirroring represents high-level interpretation of the observed actions, the less evidence it provides that this interpretation is generated by low-level motor duplication.  
Csibra's tension is evident in two famous and influential monkey mirror neuron studies by the Parma group.  In one, Umilta et al. 2001, mirror neurons were shown to fire during the observation of object-directed actions even when the object was hidden from view during the actual reaching (it was shown to the monkey before being hidden).  These same cells tended not to fire when there was no object behind the occluding screen (an empty platform was shown to the monkey).  The result was interpreted as evidence that mirror neurons are responding to the meaning or goal of the action, not the action itself. They write,

In order to activate the neurons in the hidden condition, two requirements need to be met: the monkey must “know” that there is an object behind the occluder and must see the hand of the experimenter disappearing behind the occluder. It appears therefore that the mirror neurons responsive in the hidden condition are able to generate a motor representation of an observed action, not only when the monkey sees that action, but also when it knows its outcome without seeing its most crucial part (i.e., hand-object interaction).
But if the monkey already knows the outcome, what is the point of simulating it with a motor response?  Note that the action, the movement itself, is the same in both cases.  What causes the mirror neurons to fire, then, is not the movement, but the presence or absence of the object (in the monkey's memory).  It is not a simple resonance.

The other experiment is even more famous, the report on parietal lobe mirror neurons in Science by Fogassi, et al. 2005. In this experiment, monkeys observed an experimenter reaching for an object and either bringing it to the mouth or placing it in a container. The figure here, from a 2006 Scientific American piece by Rizzolatti, shows a schematic of the set up:



The figure shows the response of a grasping-to-eat mirror neuron responding both when the monkey performs the action (1) and when he observes the action (2).  Notice, though, the the point in time when the cell starts firing during observation: it is during the reach toward the object, prior to the grasp (the red line=moment of grasp).  This is puzzling because the reach toward the object is identical in both conditions.  Only the subsequent movement, bringing to mouth or placing in container, distinguishes the action. How could the mirror neuron know ahead of time?  Is it mystically reading the mind of the experimenter?  Not at all.  

The figure is actually misleading.  If you look in the online supplemental material of the original report in Science you find this:

The container was present only in the trials in which the grasped object was subsequently placed into it. The presence of the container acted as a cue allowing the monkey to predict the most likely subsequent motor act.
It was the visual context that told the monkey ahead of time what was going to happen.  So again like the occlusion study, what determines mirror neuron activity is not the action itself but the monkey's broader understanding of the action context.  

Monkeys do not understanding because their motor system resonates with observed actions. The motor system resonates with observed actions because the monkey understands already what's going to happen.  

References

Csibra, G. (2007). Action mirroring and action understanding: An alternative account. In P. Haggard, Y. Rosetti & M. Kawato (Eds.), Sensorimotor foundations of higher cognition. Attention and Performance XII (pp. 453-459). Oxford: Oxford University Press. 


Fogassi, L., Ferrari, P. F., Gesierich, B., Rozzi, S., Chersi, F., & Rizzolatti, G. (2005). Parietal lobe: from action organization to intention understanding. Science, 308(5722), 662-667.

Hickok, G. (2014). The Myth of Mirror Neurons. New York: Norton


Umiltà, M., Kohler, E., Gallese, V., Fogassi, L., Fadiga, L., Keysers, C., & Rizzolatti, G. (2001). I know what you are doing. a neurophysiological study. Neuron, 31, 155-165. 

Tuesday, September 16, 2014

Aphasia and the brain: from syndromes to symptoms to computations

For the first 100 years of modern aphasia research (~since the 1860s) the focus was mainly on syndromes: motor (Broca's) aphasia, sensory (Wernicke's) aphasia, conduction aphasia, and so on.  Things changed after the Cognitive... er, make that the Information Processing Revolution (see discussion here or here) when symptoms came more into focus.  The symptom approach was an important advance and is still dominant, as the popular method, voxel-based lesion-symptom mapping (VLSM), highlights.

But mapping symptoms isn't the goal.  What we are really after are the computations that underlie the symptoms. Recent work by Gary Dell and colleagues suggests that this might be possible using what they call, voxel-based lesion parameter mapping (VLPM). The basic idea is this. Start with an explicit computational model of the process of interest; Dell et al. use the two-step naming model. Collect data on the symptoms in brain injured patients; for Dell et al, this is the distribution of types of naming errors. Adjust the parameters of your model to fit each patient's error pattern; semantic and phonological weights in the Dell model.  Then run your voxel-based analysis using the parameter values as your dependent measure instead of say error rate.  And it actually works.  To the extent that the model is a reasonable approximation to what's going on in the wetware (no model is "right" of course), you are now mapping computations.  Pretty cool.  All we need now is to improve our models.

Dell, G. S., Schwartz, M. F., Nozari, N., Faseyitan, O., & Branch Coslett, H. (2013). Voxel-based lesion-parameter mapping: Identifying the neural correlates of a computational model of word production. Cognition, 128(3), 380-396. doi: 10.1016/j.cognition.2013.05.007

The right theory of mirror neuron function. Guess who said it.

A quote on mirror neuron function.  I think it is spot on, as discussed in The Myth of Mirror Neurons.  Who said it? (It wasn't me.)

One of the fundamental functions of the premotor cortex is that of retrieving appropriate motor acts in response to sensory stimuli. Evidence has been provided that action retrieval can occur in response to two-dimensional patterns, color, and size and shape of three-dimensional objects. The present data indicate that in addition to these physical factors, retrieval can also occur in response to the meaning of the gestures made by other individuals. If one considers the rich social interactions within a monkey group, the understanding by a monkey of actions performed by other monkeys must be a very important factor in determining action selection. Thus, the capacity of inferior premotor neurons to select actions according to gesture meanings fits well in the conceptual framework of current theory on the functions of premotor cortex and expands it to include movement selection related to interpersonal relations.

Two tenure-track jobs at SDSU

We are writing to let you know of two tenure/tenure-track positions for Fall 2015 that we are currently conducting in the School of Speech, Language and Hearing Sciences at San Diego State University. 
Language Clinical Scientist, Bilingual emphasis,  Assistant Professor (Dr. Sonja Pruitt, Search Chair)
Tenure-track position in Bilingualism and Language Science. Required: Ph.D. in Language Science and Disorders or related field, excellence in teaching, strong research abilities, and commitment to students from diverse backgrounds. Preferred: CCC-SLP and eligibility for California licensure.  Responsibilities: undergraduate and graduate (MA/Ph.D.) teaching, supervising theses/dissertations and pursuing a research program.
Brain–based disorders and neuroplasticity, Associate Professor (Dr. Tracy Love, Search Chair)
Tenure-track position in brain-based disorders of speech, language, or cognitive processing, with adult and/or child populations, and with neuroplasticity as one focus.  Required: Ph.D. in Communication Sciences and Disorders, Linguistics, Psychology, Neurosciences or a related field, excellence in teaching, strong research abilities, and commitment to students from diverse backgrounds. Responsibilities: undergraduate and graduate (MA/Ph.D.) teaching, supervising theses/dissertations and pursuing a research program in specialty area.

Details for both positions can be found on our website (http://slhs.sdsu.edu/open-positions/)

Saturday, September 13, 2014

Job announcement: Department Head, Communication Sciences & Disorders (CSD), Penn State

Department Head, Communication Sciences & Disorders (CSD)
The Pennsylvania State University
Work Unit: College of Health & Human Development
Department: Communication Sciences & Disorders
Job Number: 52263
Date Announced: July 9, 2014

The Department of Communication Sciences and Disorders (CSD), College of Health and Human Development (HHD), at The Pennsylvania State University, invites applications for the position of Department Head to begin Fall 2015. Penn State seeks an innovative and energetic leader to build upon the existing strengths of this nationally and internationally acclaimed department.
The Department Head is expected to be a leader who promotes excellence in the full range of missions that are embodied at a comprehensive, land-grant and research intensive university such as Penn State. As a key academic leader, and in keeping with the strategic initiatives of the University and the College, the Department Head must have the ability to stimulate and facilitate research productivity, encourage interdisciplinary research, and promote and assist faculty with securing external funds to fulfill the mission of the department. The Department Head must also expand upon the current strengths of the faculty by identifying and facilitating new opportunities in undergraduate, graduate, and on-line education.

The CSD Department has a long history of tradition and excellence, and has consistently ranked in the top 10% of the communication sciences and disorders programs in the nation. Further information about the College of HHD and the Department of CSD can be found at: http://www.hhdev.psu.edu/
Qualifications: Earned doctorate; evidence of an active, focused program of research in speech, language, or hearing, or a related field; previous college teaching and administrative experience; and be eligible for appointment as a full tenured professor at The Pennsylvania State University. CCC-SLP or CCC-A certification is preferred. Significant leadership experience in a university setting, including coordination and fiscal management of department programs, is highly desirable.
Application procedures: Review of applications and nominations will begin immediately and continue until a suitable candidate is found. Candidates must apply on-line by going to the PSU Jobs Website at: https://app2.ohr.psu.edu/Jobs/External/EVMS2_External/currentap1.cfm#52263
Candidates should be prepared to provide contact information (name, address, phone number and email address) for three professional references upon request. References will not be contacted without the consent of the candidate. Direct questions to: Kathryn Drager, Ph.D., CCC-SLP, CSD Search Committee Chair, Interim Associate Dean for Research and Graduate Education, College of Health and Human Development, University Park, PA 16802-1307, 814-863-2426, or kdd5@psu.edu. Please indicate CSD Department Head Search in the subject line of email correspondence. All inquiries will be held in confidence and all applications will be held in confidence until finalists are invited to the University Park campus.

We encourage applications from individuals of diverse backgrounds. We are supportive of dual career situations.


CAMPUS SECURITY CRIME STATISTICS: For more about safety at Penn State, and to review the Annual Security Report which contains information about crime statistics and other safety and security matters, please go to http://www.police.psu.edu/clery/ , which will also provide you with detail on how to request a hard copy of the Annual Security Report.
Penn State is an equal opportunity, affirmative action employer, and is committed to providing employment opportunities to minorities, women, veterans, disabled individuals, and other protected groups.

Friday, September 12, 2014

Clarifying the auditory dorsal stream, again: a comment on Rauschecker 2014

Josef Rauschecker has a new paper out in Frontiers titled, "Is there a tape recorder in your head? How the brain stores and retrieves melodies." It's worth a look.  The problem of coding sequences of information is an important, and poorly understood one.

But that's not I want to highlight here.  Instead I want to put some comments of Rauschecker's in their proper context, i.e., the context of the neuroscience of hearing that exists outside of his laboratory. He writes,  
The dorsal stream was originally defined by its involvement in auditory spatial processing (Rauschecker and Tian, 2000) and movement in space (Warren et al., 2002). This is still believed to be correct (Rauschecker, 2012), but the role of the dorsal stream has been expanded to include sensorimotor integration and control in more general terms (Rauschecker and Scott, 2009Rauschecker, 2011), including the representation of sequences.
As I pointed out in this post, the idea of dual streams in auditory processing pre-date Rauschecker and Tian by at least a half a century, and can trace their route back even farther to Carl Wernicke who argued for the existence of two auditory pathways, one that projects to the motor system and on that projects to the conceptual system.

Secondly, the idea that the dorsal auditory stream processes spatial information has been questioned and re-questioned by the likes of Robert Zatorre, John Middlebrooks, as well as by work in my own lab headed by former grad student Kevin Smith.  A discussion of why, from a purely conceptual standpoint, "spatial processing" cannot possibly be a "stream" can be found in this review by Hickok & Saberi.  To summarize our point, streams are organized around computational tasks (what you do with information) not around information types.  So "This is still believed to be correct" is better stated as, "This is still believed to be correct, by Rauschecker."

Good to see, though, that Rauschecker has correctly acknowledged the "expansion" of the role of the dorsal stream to include sensorimotor integration.  I'm sure his omission of Hickok & Poeppel, 2000, 2004, 2007, Wise et al. 2001, Buchsbaum et al. 2001, Hickok et al. 2003, 2009, 2011, Pa & Hickok, 2008, Isenberg et al. 2012, to name few, was a merely a proofing error.

The rest of the references for Rauschecker 2014:


Buchsbaum, B., Hickok, G., & Humphries, C. (2001). Role of Left Posterior Superior Temporal Gyrus in Phonological Processing for Speech Perception and Production. Cognitive Science, 25, 663-678. 


Hickok, G., & Poeppel, D. (2000). Towards a functional neuroanatomy of speech perception. Trends Cogn Sci, 4, 131-138. 


Hickok, G., & Poeppel, D. (2004). Dorsal and ventral streams: A framework for understanding aspects of the functional anatomy of language. Cognition, 92, 67-99. 


Hickok, G., & Poeppel, D. (2007). The cortical organization of speech processing. Nature Reviews Neuroscience, 8(5), 393-402. 

Hickok, G., Buchsbaum, B., Humphries, C., & Muftuler, T. (2003). Auditory-motor interaction revealed by fMRI: Speech, music, and working memory in area Spt. Journal of Cognitive Neuroscience, 15, 673-682. 

Hickok, G., Okada, K., & Serences, J. T. (2009). Area Spt in the human planum temporale supports sensory-motor integration for speech processing. J Neurophysiol, 101(5), 2725-2732. doi: 91099.2008 [pii]
10.1152/jn.91099.2008

Hickok, G., Houde, J., & Rong, F. (2011). Sensorimotor integration in speech processing: computational basis and neural organization. Neuron, 69(3), 407-422. doi: S0896-6273(11)00067-5 [pii]10.1016/j.neuron.2011.01.019

Isenberg, A. L., Vaden, K. I., Jr., Saberi, K., Muftuler, L. T., & Hickok, G. (2012). Functionally distinct regions for spatial processing and sensory motor integration in the planum temporale. Hum Brain Mapp, 33(10), 2453-2463. doi: 10.1002/hbm.21373


Middlebrooks, J. C. (2002). Auditory space processing: here, there or everywhere? Nat Neurosci, 5(9), 824-826.

Pa, J., & Hickok, G. (2008). A parietal-temporal sensory-motor integration area for the human vocal tract: Evidence from an fMRI study of skilled musicians. Neuropsychologia, 46, 362-368. 


Smith, K. R., Okada, K., Saberi, K., & Hickok, G. (2004). Human cortical motion areas are not motion selective. Neuroreport, 9, 1523-1526.

Smith, K. R., Saberi, K., & Hickok, G. (2007). An event-related fMRI study of auditory motion perception: no evidence for a specialized cortical system. Brain Res, 1150, 94-99. 

Smith, K. R., Hsieh, I. H., Saberi, K., & Hickok, G. (2010). Auditory spatial and object processing in the human planum temporale: no evidence for selectivity. Journal of Cognitive Neuroscience, 22(4), 632-639. doi: 10.1162/jocn.2009.21196

Wise, R. J. S., Scott, S. K., Blank, S. C., Mummery, C. J., Murphy, K., & Warburton, E. A. (2001). Separate neural sub-systems within "Wernicke's area". Brain, 124, 83-95. 


Zatorre, R. J., Bouffard, M., Ahad, P., & Belin, P. (2002). Where is 'where' in the human auditory cortex? Nat Neurosci, 5(9), 905-909. 

Monday, September 8, 2014

Why "embodied simulation" is a vacuous concept - from Myth of Mirror Neurons

From "Chapter 6: The Embodied Brain" in The Myth of Mirror Neurons:

To say that a cognitive operation is accomplished via simulation doesn’t simplify the problem, it just hands it off to another domain of inquiry, in this case sensory and motor information processing. It’s akin to a hypothetical rogue head-of-state who calls in his top physicists and demands that they work out how to build a nuclear weapon. The physicists come back a week later and proclaim that they’ve got it all figured out: 

PHYSICISTS: We have determined that Oppenheimer and his team have succeeded in building a nuclear weapon. All we need to do is simulate what they did.
HEAD-OF-STATE: Great! So how did they do it?
PHYSICISTS: We don’t know. But simulating their methods will definitely work.
.
.
MIRROR NEURON THEORISTS: We have determined that when we carry out an action of our own we understand the meaning of that action. When we observe someone else’s action, all we need to do is simulate that action in our own motor system and we will achieve understanding.
SKEPTIC: Yes, but how do we understand the meaning of our own actions in the first place?
MIRROR NEURON THEORISTS: We don’t know, but we know that simulating that process will work.