Thursday, August 21, 2014

Assistant Professor in Cognitive Neuroscience, Brown University, Providence, R.I. 02912

The Department of Cognitive, Linguistic, and Psychological Sciences (CLPS) invites applications for a
tenure-track Assistant Professor position in cognitive neuroscience beginning July 1, 2015. All
candidates utilizing methodological approaches such as neuroimaging to address basic questions in any
area of cognitive neuroscience will be considered. Exceptional candidates whose research addresses
topics relevant to psychiatric disorders are particularly encouraged to apply. This appointment will be
made in conjunction with the Department of Psychiatry and Human Behavior (DPHB) and the
interdepartmental Brown Institute for Brain Science (BIBS) as part of an expansion that includes seven
new faculty positions. Brown has a highly interdisciplinary research environment in the study of mind,
brain, behavior, and language, including the recently created CLPS Department housed within a newly
renovated, state-of-the-art building in the heart of campus. The affiliated appointment in the DPHB will
ensure access to patient populations through Brown's affiliated teaching hospitals.

QUALIFICATIONS
PhD Required
Applicants must have broad teaching abilities in related areas at both the undergraduate and graduate
levels, a high-quality research program, and an appropriate record of accomplishment.

APPLICATION INSTRUCTIONS
Curriculum vitae, reprints and preprints of publications, a maximum two-page statement of research
interests, a one-page statement of teaching interests, and three letters of reference should be submitted
on-line as PDFs to http://apply.interfolio.com/25621. Applications received by October 31, 2014 will
receive full consideration.

Brown University is committed to fostering a diverse and inclusive academic global community; as an
EEO/AA employer, Brown considers applicants for employment without regard to, and does not
discriminate on the basis of, gender, race, protected veteran status, disability, or any other legally

protected status.

Wednesday, August 20, 2014

Post-Doc position, Sleep and Cognition Lab, UC Riverside


The Sleep and Cognition (SaC) Lab of the Department of Psychology at the University of California, Riverside has an open position for a postdoc researcher. This researcher will be investigating mechanisms of memory encoding, consolidation, and retrieval by using event-related potential (ERP/EEG) during waking and sleep. Successful candidates should have experience in memory research and EEG methodologies, as well as programming skills. Experience in sleep research is not essential. Position is available immediately. Researchers must possess a doctoral degree. The University of California offers excellent benefits. Salary is based on research experience. The initial appointment is for 1 year with a possibility of extension. Please send your CV, statement of research interests and the names of three references or make inquires to Sara C. Mednick smednick@ucr.edu.

Tuesday, August 19, 2014

Mirror neurons may have been inadvertently trained into laboratory macaques

Even though there is a growing consensus that mirror neurons are not the basis of action understanding (or language, theory of mind, autism, etc.), the question remains, What are mirror neurons doing? There are now a couple of good theories.  One is the idea promoted by Cecelia Heyes that observation of self-action results in an association between executed and observed actions, which is then generalized to others' actions.  Another is the view proposed by Michael Arbib that mirror neurons start out as part of a motor control circuit, providing visual feedback on ongoing actions and then later get recruited to bolster action understanding.  

Here's another idea: mirror neurons are not naturally occurring in wild macaques. Instead, they are trained into the lab animals by pairing experimenter object-related actions with the monkey’s own object directed actions.

Consider this quote about the training procedure from a 2001 report (Umlita et al. 2001):
Before starting the neurophysiological experiments, the monkeys were habituated to the experimenters. They were seated in a primate chair and trained to receive food from the experimenters. Monkeys received pieces of food of different size, located in different spatial locations. This pretraining was important for subsequent testing of the neuron’s motor properties … and for teaching the animal to pay attention to the experimenters.
It appears that the Parma group’s training procedures involved exposing the monkeys to a good deal of human actions that are directly related to the monkey’s task of reaching for and interacting with objects. 
Why do I suspect that mirror neurons didn’t exist before this training?  Because there is strong evidence for the development of mirror-like responses where previously they did not exist. 
In the foundational Gallese et al. 1996 report, mirror neurons did not respond to grasping with pliers.  This was viewed as evidence for mirror action specificity and biological relevance: monkeys don’t grasp with pliers so they can’t mirror that action.  However, a later study showed that tool-related mirror neurons do exist, after the monkey is repeatedly exposed to humans picking up and poking items with tools. I quote from that report,
 …observations made in our laboratory showed that at the end of a relatively long period of experiments, it was possible to find mirror neurons responding also to actions made by the experimenter with tools
Did this lead to a new understanding of tool use in the macaque observers? Not so much.  After training, the monkey was presented with food that was just out of reach along with the stick that the experimenters had used to poke food during training (and which generated tool-related mirror neuron responses):
the monkey never attempted to use the tool for reaching food, although in the first minutes after the stick was available, the monkey grasped it and bit it.
I suggest (Hickok, 2014) that the action-related "canonical" mirror neurons discovered in the 1990s and that formed the foundation of new theories of action understanding, language, theory of mind, autism and the rest, formed in the same way, by associations built-up in the sensorimotor system via the training procedure.  This hypothesis is easy to test.

References

Gallese, V., Fadiga, L., Fogassi, L., & Rizzolatti, G. (1996). Action recognition in the premotor cortex. Brain, 119 ( Pt 2), 593-609.

Hickok, G. (2014). The myth of mirror neurons: The real neuroscience of communication and cognition. New York: Norton.

Ferrari, P. F., Rozzi, S., & Fogassi, L. (2005). Mirror neurons responding to observation of actions made with tools in monkey ventral premotor cortex. Journal of Cognitive Neuroscience, 17(2), 212-226.


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, August 12, 2014

UC Irvine - Dept of Cog Sci - Associate or Full Professor - Computational Neuroscience

RECRUITMENT PERIOD

Open Jul 25, 2014 through Nov 15, 2014
If you apply to this recruitment by Nov 15, 2014, you will have until Nov 30, 2014 to complete your application.

DESCRIPTION

The Department of Cognitive Sciences (www.cogsci.uci.edu) at the University of California, Irvine (UCI) invites applications for a faculty position at the Associate or Full Professor level. We are especially interested in candidates who use mathematical, computational, or robotics approaches to study the neural basis of cognition in any of these areas: (1) vision, hearing, and attention; (2) memory and decision-making; (3) learning and development; (4) language. Applicants whose research relates to human behavior are preferred.
A strong record of publications and extramural funding is essential. Exceptional candidates at the Assistant Professor level will also be considered.
The online application includes: A cover letter, CV, research and teaching statements, 3 recent publications, and contact information for 3-5 referees. Interested candidates can apply for the position at: https://recruit.ap.uci.edu/apply/JPF02452. To ensure full consideration, please complete the application by November 15, 2014.
The University of California, Irvine is an Equal Opportunity/Affirmative Action Employer committed to excellence through diversity. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, disability, age, protected veteran status, or other protected categories covered by the UC nondiscrimination policy.

LEARN MORE

More information about this recruitment: http://www.cogsci.uci.edu/cs_jobs

REQUIREMENTS

DOCUMENTS

  • Cover Letter
  • Curriculum Vitae - Your most recently updated C.V.
  • Statement of Research
  • Statement of Teaching
  • Publication #1 - Please provide 3 recent publications.
  • Publication #2 - Please provide 3 recent publications.
  • Publication #3 - Please provide 3 recent publications.

REFERENCES

3-5 references required (contact information only)

HOW TO APPLY

  1. Create an ApplicantID
  2. Provide required information and documents
  3. If any, provide required reference information

Monday, August 11, 2014

Assistant Professor (Tenure-Track) in Developmental Neuroscience - CMU

Assistant Professor (Tenure-Track) in Developmental Neuroscience 

The Department of Psychology and the Center for the Neural Basis of Cognition (CNBC) at Carnegie Mellon University seek to fill a tenure-track faculty position in developmental neuroscience at the assistant professor level. The position is funded by a generous gift from Ronald J. and Mary Ann Zdrojkowski as a Career Development Chair to attract young researchers to further our understanding of how humans develop. A successful candidate will be committed to high-quality teaching and should have a research background that includes core areas within cognitive neuroscience, developmental neuroscience, or social neuroscience, a strong grounding in theory, cutting-edge methods, and an interest in collaborations. We are especially interested in candidates with research interests in the neural basis of human learning, development, and plasticity. 

Carnegie Mellon is committed to an expansion of its faculty and facilities in the area of mind and brain research and is a highly supportive environment for scientists who seek to span multiple disciplines or employ multiple methodologies in their research. Facilities include a state-of-the-art MRI facility (http://www.sibr.cmu.edu), EEG, NIRS, and MEG systems, and large-scale, high-performance computing clusters. The appointment will be joint between the Department of Psychology and the CNBC ñ an interdisciplinary and collaborative research and training center jointly administered across Carnegie Mellon University and the University of Pittsburgh. The candidate will join a growing and highly interactive computational, cognitive, and neuroscience community. 

Carnegie Mellon offers highly competitive salaries and start-up packages in an attractive and highly livable urban environment. Applications will begin to be reviewed on October 1, 2014. Applications, including a cover letter, a curriculum vitae, research and teaching statements, copies of no more than 3 relevant papers, and the contact information for at least three individuals who have been asked to provide letters of reference should be submitted electronically in PDF format to the following email address:faculty-search@cnbc.cmu.edu

Applications should indicate citizenship and, for non-US citizens, current visa status. Only complete applications in PDF format will be considered. Concurrent with the submission of their application, applicants should also arrange for at least three reference letters in PDF format to be sent directly to: faculty-search@cnbc.cmu.edu. If you encounter technical problems, please write to: faculty-search@cnbc.cmu.edu. Carnegie Mellon University is an affirmative action/equal opportunity employer; we invite and encourage applications from women and minorities. 


Carnegie Mellon University does not discriminate in admission, employment, or administration of its programs or activities on the basis of race, color, national origin, sex, handicap or disability, age, sexual orientation, gender identity, religion, creed, ancestry, belief, veteran status, or genetic information. Furthermore, Carnegie Mellon University does not discriminate and is required not to discriminate in violation of federal, state, or local laws or executive orders. Inquiries concerning the application of and compliance with this statement should be directed to the vice president for campus affairs, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, telephone 412-268-2056.

Friday, August 8, 2014

How useful is neural oscillation entrainment?

I've been struggling with this question for a while.  I haven't looked at it deeply.  It's more like a nagging ache that I've been meaning to examine closely at some point.  Here's the basic observation/idea in the auditory domain:

-Observation #1: Neural oscillations tend to entrain in the phase of their response to periodic stimuli.
-Observation #2: Many natural sounds, such as speech, are quasi periodic.
-The Claim: Oscillation entrainment facilitates perception by synching periods of maximal neural sensitivity to temporal windows in the stimulus stream that contain the most useful information.

I like this idea.  It is a reasonable idea.  I don't know if it is correct.  The alternative possibility, given the two observations is that neurons and neural networks oscillate just because--i.e., build a network with excitatory-inhibitory interactions, balance them so you don't get runaway excitation or constant suppression, and it tends to oscillate and will tend to reset it's phase with inputs (this is a fact, btw).  On this alternative possibility, phase-locked oscillations are more of a by product of network design, not something that was selected for to enhance perception.  In fact, it's conceivable that phase locking to a stimulus could actually interfere with neural signal processing, although not sufficiently to preclude the systems useful as a signal processor.

So what we need to show to decide whether oscillation entrainment is a design feature to enhance perception or whether it is a spandrel-like emergent property is examples of perceptual enhancement resulting from neural oscillation entrainment.

A recent paper by Henry & Obleser (Frequency modulation entrains slow neural oscillations  and optimizes human listening behavior, PNAS) claims to do just this.  They used an FM modulating stimulus and inserted gaps at various phases of the modulation.  The listener's task was to detect the gaps.  They found that listener performance was affected by the position of the gap relative to phase angle.  Cool!  But it wasn't consistent across subjects.  Bummer!  Different listeners had different phases that led to best performance.  BUT, when they looked at the EEG signal oscillation phase, then a consistent relation was observed.  Cool!  Behavioral was tied to neural, not signal rhythmicity.

This sounds like a very nice and important result, which is why it's in PNAS.  But again I have a nagging worry.  Maybe it's nothing to get twisted up about but here it is: If the point of neural phase locking is to time neural sensitivity to stimulus rhythmicity, then shouldn't we worry if there is no consistent relation between stimulus phase and perceptibility?  You only see the relation when you look at the neural oscillations themselves.  Maybe different listeners just have different neural delays. But by half a stimulus cycle?  Makes me worry.

So despite how appealing the theory, and how suggestive the growing collection of results is, I still worry that oscillations are doing all that much--at least on purpose.

Wednesday, August 6, 2014

Never confuse a statistically reliable behavioral effect with cognitive/computational relevance

There are plenty of example of statistically reliable effects in the embodied cognition literature.  Stimulation of motor speech areas modulate performance on speech perception tasks; reading sentences about closing drawers makes one faster in generating pushing movements; [insert favorite result here]. Let's assume all of these effects replicate.  I have no particular reason to doubt them.

I do have a problem with the knee jerk interpretations though.  Motor stimulation modulates speech perception, therefore, the motor system is critical for speech perception.  Comprehending sentences about pushing facilitates pushing actions, therefore, motor acts of pushing are part of the concept of pushing.

It's a faulty inference.

The same inferential error has been recognized and called out for lesion work: just because a brain area, when damaged, causes deficits in ability x, doesn't mean that the brain area is "doing x".  Bilateral visual cortex damage will cause naming deficits, but isn't the neurological seat of naming.

A lot of work coming out of the embodied cognition world is making the same inferential error, I suggest.

Tuesday, August 5, 2014

Myth of Mirror Neurons comment forum

Now that the Myth of Mirror Neurons is starting to ship, I'd like to hear your thoughts.  Use the comment box on this post to ask questions, correct my errors, provide counterpoints, or whatever.
-greg

Monday, August 4, 2014

Dual streams in audition -- in case you thought the idea is derivative of Ungerleider and Mishkin

Ungerleider and Mishkin often get the credit for originating dual stream sensory processing models. But, despite the critical importance of their contributions, the idea that the visual system is computationally bifurcated was well established by the time Ungerleider and Mishkin published their hugely influential chapter on the “Two Cortical Visual Systems” in 1982.  They write,

It has been our working hypothesis (Mishkin 1972; Pohl 1973) that the ventral or occipitotemporal pathway is specialized for object perception (identifying what an object is) whereas the dorsal or occipitoparietal pathway is specialized for spatial perception (locating where an object is). This distinction between the two types of visual perception is not new (see, for example, Ingle 1967; Held 1968). [(Ungerleider and Mishkin, 1982) p. 549]

What the 1982 paper did was make the case that the two streams in the macaque monkey were cortical, that the origin of them was the striate visual cortex.  Important stuff, but as with almost all big ideas, it was built on a solid pre-existing foundation.  

In the auditory domain, Josef Rauschecker is often credited with originating the view that auditory cortex is subdivided into two processing streams, a dorsal “where” stream and a ventral “what” stream (Rauschecker, 1998; Rauschecker and Scott, 2009). However, the idea of dual auditory streams predates Rauschecker’s influential papers by several decades. Deutsch and Roll proposed separate “what” and “where” mechanisms for hearing in their 1976 report (Deutsch and Roll, 1976) citing then recent animal neurophysiological evidence for the distinction (Evans and Nelson, 1973). And a historical precedent to a dual-stream model of audition goes even farther back to the work of Poljak who in 1926 discussed the various subdivisions in “the connections of the acoustic nerve” and came to a conclusion that foreshadowed current dual-stream ideas by the better part of a century.

The constituent parts of the central auditory system have mostly a double function – viz. to conduct the peripheral auditory sensations to the prosencephalon [forebrain] on the one hand, and on the other, to establish a reflex path for the cochlear stimuli to the motor mechanisms of the brain stem. (Poljak, 1926)(p. 468)

We could, of course, go back even farther and point to Wernicke’s classic language/brain model, which held that the auditory system had two connections, one to the widely distributed conceptual system and the other to the motor speech system.  Wernicke, as far as I can tell, proposed the original dual stream model of cortical processing. 

Deutsch, D., & Roll, P. L. (1976). Separate "what" and "where" decision mechanisms in processing a dichotic tonal sequence. J Exp Psychol Hum Percept Perform, 2, 23-29.
Evans, E. F., & Nelson, P. G. (1973). On the relationship between the dorsal and ventral cochlear nucleus. Experimental Brain Research, 17, 428-442.
Held, R. 1968. ”Dissociation of visual functions by deprivation and rearrangement.”
Psychol. Forsch. 31: 338-348.
Ingle, D. (1973). Two visual systems in the frog. Science, 181, 1053-1055.
Pohl, W. (1973). Dissociation of spatial discrimination deficits following frontal and parietal lesions in monkeys. J Comp Physiol Psychol, 82, 227-239
Poljak, S. (1926). The connections of the acoustic nerve. Journal of Anatomy, 60, 465-469.
Rauschecker, J. P. (1998). Cortical processing of complex sounds. Current Opinion in Neurobiology, 8, 516-521.
Rauschecker, J. P., & Scott, S. K. (2009). Maps and streams in the auditory cortex: nonhuman primates illuminate human speech processing. Nature Neuroscience, 12, 718-724.
Ungerleider, L. G., & Mishkin, M. (1982). Two cortical visual systems. In D. J. Ingle, M. A. Goodale & R. J. W. Mansfield (Eds.), Analysis of visual behavior (pp. 549-586). Cambridge, MA: MIT Press.

Saturday, August 2, 2014

The fourth brain myth

My NYT OpEd piece on brain myths originally included four: two old, one that has just recently taken hold (mirror neurons) and a fourth that is in the earliest stages of the neuromyth life cycle.  This fourth myth didn't make the editorial cut due to an 800 space limit.  But through the magic of blogging, here it is.

Another 21st century neuromyth is just now being born, the idea that if neuroscientists can map the structure of the brain, from micro to macro circuit, we will achieve a complete understanding of the mind.  The data around which this infant myth is coalescing is the flurry of technological achievements in brain mapping: functional MRI, diffusion-based connectivity, optogenetics, see-through “Clarity” brain technology, and so on.  For the first time in history the prospects of mapping the entire brain seems possible.  There is no question that this research effort will bear fruit, but a complete circuit diagram of the brain won’t explain how the mind works any more than a complete sequence of the human genome explains how the sequence builds a human.  There is simply more to the problem than a sequence or circuit diagram. What we need in addition is a map of the relation between the circuit diagrams, their dynamics, and equally detailed cognitive/computational “maps” of the mental abilities they create.  A number of us in the neuroscience community are making this point already (e.g., Gary Marcus’ recent NYT Op-Ed, “The Trouble with Brain Science” 11 July 2014) and I suspect that under direct questioning many brain mapping practitioners would agree that the maps aren’t the whole story. But given the floodlight of attention cast on the push to map the brain, together with the natural history of science myths, it’s not hard to predict the development of a colossal myth regarding what it will take to truly understand how the brain creates the mind.