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Cognitive Neuroscience

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					Cognitive Neuroscience


 Speech &
 Language

             Methods

 Emotion


             Attention

 Memory &
 Knowledge


               October 2009 entry
                    MEDICAL RESEARCH COUNCIL
                 COGNITION AND BRAIN SCIENCES UNIT


    15 Chaucer Road
    Cambridge
    CB2 7EF

    Tel: 01223 355294

    Fax: 01223 359062

    grad-admin@mrc-cbu.cam.ac.uk

    http://www.mrc-cbu.cam.ac.uk


                                      CONTENTS

    The Medical Research Council       3

    Graduate Studies at the CBSU       3

    The Cambridge Graduate Programme in Cognition and Brain Sciences   4

    Application procedure   5

    Research at the CBSU    6

    Attention   6

    Emotion     10

    Memory and Knowledge         12

    Speech and Language     14

    Methods     19

    Appendix 21

    CBSU procedure for Postgraduate Students 21


2
                      THE MEDICAL RESEARCH COUNCIL

The UK Medical Research Council (MRC) is a national organisation funded by the UK
taxpayer. We promote research into all areas of medical and related science with the
aims of improving the health and quality of life of the UK public and contributing to the
wealth of the nation.

The Medical Research Council (MRC)’s mission is set out in its Royal Charter.
In summary, the MRC’s purpose is to:

•	    Encourage	and	support	high-quality	research	with	the	aim	of	
      improving human health.

•	    Produce	skilled	researchers,	and	to	advance	and	disseminate	knowledge	
      and technology to improve the quality of life and economic competitiveness
      of the UK.

•	    Promote	dialogue	with	the	public	about	medical	research.

The MRC supports medical research by providing funding for research programmes
and infrastructure, and by investing in training and employment both in universities
and in the MRC’s own research centres. Most of the MRC units are based on or
near university campuses or hospitals and are home to some of the UK’s best
biomedical scientists which provide an important multidisciplinary training environ-
ment for researchers. Many of them provide a national focus of expertise in particular
areas of science. The Cognition and Brain Sciences Unit (CBSU), located in pleasant
garden surroundings in the city of Cambridge, is one such institution.



                      GRADUATE STUDIES AT THE CBSU

Applications are invited for research in any topic falling within the research interests
of staff. For eligible applicants, several quota studentships are available (for
eligibility see MRC Postgraduate Studentships Handbook). Applications should reach
us by 13 February 2009, although in exceptional cases late applications may be
considered, especially from those with alternative sources of funding. Please note that
if you are applying for sources of funding other than an MRC Studentship (eg Gates,
ORS etc), you should check the relevant deadlines and ensure that your application is
submitted in good time.

Students at the CBSU are registered as PhD candidates at the University of Cambridge
and are required to fulfil the admissions requirements of the University. (These can be
found in the University Prospectus). General enquiries about awards to overseas
students, fees etc can be made to the Secretary, Board of Graduate Studies, 4 Mill
Lane, Cambridge CB2 1RZ. Initial registration is not for any particular degree or
qualification, and students are registered for the PhD on satisfactory completion of
their first year of study (see Appendix).

You become a member of the University of Cambridge Graduate School of Life
Sciences which oversees the progress of your research and offers additional facilities
and courses. While carrying out your research you are able to enjoy all the advantages
of the University facilities and the collegiate system. There are substantial contacts

                                                                                            3
    with other experimental, clinical and neuroscience groups in the University of
    Cambridge, including the Departments of Experimental Psychology, Neurology, and
    Psychiatry, and the Wolfson Brain Imaging Centre (WBIC) at Addenbrooke’s Hospital.

    Students attend a variety of Unit Seminars given by distinguished scientists and are
    also able to present their research by giving seminars. They are able to draw from the
    CBSU’s panels of research volunteers, both normal and clinical, and enjoy the benefits
    of superb computing facilities and support staff, including a Graphics and Multimedia
    Officer.

    The CBSU has excellent facilities for experimental behavioural studies involving
    normal populations and patients with brain damage, as well as institutional links with
    Addenbrooke’s hospital giving access to various types of patient populations,
    including stroke and progressive neural degenerative diseases. There is an fMRI
    (3Tesla) scanner on the premises, and also a MEG facility and an EEG laboratory.
    Through its partnership with the University of Cambridge Wolfson Brain Imaging
    Centre, the CBSU has excellent access to PET and to additional fMRI (3 Tesla)
    neuro-imaging facilities. The CBSU also offers state of the art computing facilities,
    supporting Unix, PC, and Mac platforms, and handling the large volumes of
    neuro-imaging data as well as extensive computational modelling. All students have
    their own networked desktop computer, with internet access through JANET.


         The Cambridge Graduate Programme in Cognition and Brain Sciences

    CBSU students are full members of the Cambridge Graduate Programme in Cognition
    and Brain Sciences, which has been jointly established by the Unit and the
    Departments of Experimental Psychology and Psychiatry. This consists of a weekly
    series of theoretical seminars presented by senior researchers. The following are
    examples of past seminar topics and speakers:

    •	      William	Marslen-Wilson:	Speech,	language	and	the	brain.	

    •	      Rhodri	Cusack:	Neuroimaging	with	MRI:	combining	physics	and	physiology	to		
            assess brain function.

    •	      Michael	Shadlen:	A	neural	mechanism	of	decision	making,	or	How	I	Learnt	to		
            Stop Worrying and Love the Bound.

    •	      Friedemann	Pulvermüller:	What	is	meaning,	does	it	reside	in	the	brain,	and,	if		
            yes, where?

    •	      Liz	Pellicano:	Adaptive	face-coding	mechanisms	in	typically	developing	children		
            and children with autism spectre disorder.

    •	      Karalyn	Patterson:	Does	Sudoku	require	semantic	memory?

    •	      John	Duncan:	Functional	brain	imaging	as	a	physiological	method.	

    •	      Trevor	Robbins:	Executive	functions	of	the	prefrontal	cortex:	theoretical	and		
            methodological issues from converging cross-species studies.


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•	    Matt	Davis:	Pictures	of	data:	improving	scientific	illustrations.

•	    Jessica	Grahn:	Auditory	processing:	from	illusions	to	the	musical	brain.

•	    Rik	Henson:	The	Systems	Neuroscience	of	Human	Memory

•	    Tim	Croudace:	An	introduction	to	statistical	modeling	with	psychometrics	and		
      structural equations.

•	    Barbara	Sahakian:	Neuroethical	issues	in	cognitive	enhancement	and	
      neuroimaging.

•	    Jon	Simons:	A	slim	grip	on	reality?	Linking	source	memory	and	psychosis.


                            APPLICATION PROCEDURE

Application forms may be obtained from:

Graduate Administration, MRC Cognition and Brain Sciences Unit, 15 Chaucer Road,
Cambridge, CB2 7EF

email: grad-admin@mrc-cbu.cam.ac.uk

Or downloaded from the University of Cambridge Web site:

http://www.admin.cam.ac.uk/offices/gradstud/admissions/

All applications must be submitted via the University of Cambridge admissions pro-
cess. Please note that there is no separate form for applying to us specifically, nor for
applying for MRC studentship funding. In your application you should name the MRC
Cognition & Brain Sciences Unit as the Dept. you wish to be considered by, and the
University Board of Graduate Studies will forward your application to us. Our course
code is NUAPBL22.

You can apply on-line if you prefer:

http://www.admin.cam.ac.uk/univ/gsprospectus/applying/online.html

Once you have submitted your application, please inform us by emailing
grad-admin@mrc-cbu.cam.ac.uk to ensure that we know that it is on the way.

Our closing date for Studentship applications is 13th February 2009, but please note
that in order to meet the deadlines for certain funding - eg ORS, Gates- you may need
to submit your application much earlier than this. You should always check funder’s
own deadlines).

Studentship interviews usually take place in March/April.




                                                                                            5
                                    RESEARCH AT THE CBSU

    The Cognition and Brain Sciences Unit has a long and distinguished history and
    international reputation. At present it houses around 100 scientists, students and
    visiting workers, and research is divided into four general programmes, dealing
    respectively with Attention, Emotion, Memory and Knowledge, and Speech and
    Language. Within these groups, methods include experimental cognitive psychology,
    neuropsychology, and neuroimaging using EEG, MEG and fMRI. An additional
    programme area - Methods - covers quantitative research methods and statistics.

    Details of research in the various groups can be seen on our website at
    http://www.mrc-cbu.cam.ac.uk/research/ and below we give a flavour of each group
    and the individual research areas of some of our senior scientists.


                                          ATTENTION

    The core theoretical objective of this programme is to understand basic processes
    of selective attention and the distributed brain systems on which they depend.
    A number of key areas are represented in this research, including:

    •	    Basic	questions	of	sensory	grouping,	organization	and	representation	within		
          and between the modalities of vision, hearing and body sense.

    •	    Attentional	competition	and	focus,	including	studies	of	selective,	divided	and		
          sustained attention.

    •	    Cognitive	control	and	its	contribution	to	intelligence,	in	particular	the	study	of		
          frontal lobe functions.

    •	    Clinical	applications,	including	studies	of	unilateral	spatial	neglect	in	multiple		
          spatial frames of reference.

    Individual areas of research:

    Rhodri Cusack

    It is a good general rule that the processes our brains perform best are those we
    are least aware of. For example, while it is easy for us to recite the rules of mental
    arithmetic, we are very poor at it, even when compared to the simplest of calculators.
    In contrast, the way we organise the vast jumbles of information arriving from our
    senses into coherent objects, or the subsequent selection of relevant ones, seem trivial
    to us, but these are extremely hard, complex problems. Cognitive neuroscience
    provides an excellent tool for identifying how these tasks are performed by the brain:
    a combination of neuroimaging, neuropsychology and electrophysiology can reveal
    the underlying representations and processes. I work primarily using functional MRI
    and neuropsychology to study the structuring of information (spanning perception,
    attention, memory & cognition) and would welcome candidates for PhDs in this or
    related areas. Perhaps our work will help us understand even those processes humans
    perform best! Additionally, as a new tool, MRI is constantly developing, and I would
    also welcome applications from those with a mathematics, physics or engineering
    background wanting to work to develop new methods for medical imaging.


6
John Duncan

The study of attention is especially well suited to the interdisciplinary approach
of current cognitive neuroscience. We use methods of experimental cognitive
psychology, neuropsychology, and functional brain imaging to investigate perceptual
attention within and between the sensory modalities, and processes of top-down or
executive control. Problems addressed include selection of behaviourally-relevant
information from a visual scene, the time course and neurophysiology of attentional
shifts, attentional impairments including simultanagnosia and unilateral neglect, the
role of the frontal lobes in goal-directed behaviour and its relation to normal
intelligence. Key theoretical constructs include competition for representation in
multiple sensory and motor systems of the brain, and top-down bias of that
competition by relevance to current behavioural concerns. Our hypothesis is that
attentional functions are not the province of particular neural systems or components
of the sensorimotor network. Instead, “attention” is a representational state emerging
from the integrated activity of that network as a whole.

Tom Manly

Brain injury often results in difficulties in attention, awareness and executive
functions. These can range from striking deficits in noticing information from one side
of space (unilateral spatial neglect) through to ‘executive’ problems in maintaining
goal directed behaviour, planning, and inhibition. The sometimes very selective
damage to such capacities has raised questions about how these complex functions
develop, are manifested in the healthy brain, and how they may act to influence the
function of more basic perceptual and output systems. The CBSU has a long history of
innovations in these areas (from the early work of Broadbent, Mackworth etc on
attention and vigilance through to the work of, for example, Alan Baddeley, Tim
Shallice, Paul Burgess, Tony Marcel and John Duncan on executive functions and
awareness).

The Unit now has a thriving cross-disciplinary programme, including the use of fMRI
and MEG functional imaging, as well as work with patients and healthy volunteers,
directed at understanding these higher level capacities. One of the main aims of our
part of the programme lies in applying these developments to neuropsychological
rehabilitation and, in turn, using the result from our work with patients to further
illuminate/constrain models of normal function. Given that attention and executive
abilities may have a particular role in facilitating adaptive recovery, developments in
clinical applications in this area hold great potential to improve outcomes for patients.
In this work we enjoy excellent links with the Oliver Zangwill Centre (a leading
international unit for rehabilitation after brain injury based in Ely) and with stroke
and other neurological services at Addenbrooke’s Hospital. Cambridge is also ideally
placed for increased liaison with developmental and adult psychiatry services for
specific projects.

In addition, the Unit has excellent facilities and methods support for functional
imaging studies and access to a large group of healthy volunteers. Although the broad
themes of the programme relate to how attention/executive functions are best
assessed and facilitated through targeted intervention (and indeed their role in
recovery and outcome more generally) – the details and methods used in studies
varies considerably. In this respect we welcome innovative proposals that could range
from work with clinical groups through to functional imaging/behavioural work with


                                                                                            7
    healthy volunteers. Typically, PhD projects would combine aspects of each – which is
    often of benefit in providing the broadest possible experience to students.

    As an illustration, the following topics have been addressed in recent PhD projects:

    •	    Spatial	function	and	alertness:	Work	with	patients	showing	unilateral	neglect	
          has suggested that the debilitating spatial biases may be significantly reduced
          by increased alertness. In attempting to understand this effect (and as a basis
          for a more general model for the impact of frontal function on recovery), two
          substantial projects have considered whether children with low levels of
          alertness may experience a form of developmental unilateral neglect and
          whether modulations of alertness in the healthy population show similar
          patterns. These projects have included studies with healthy adults and children,
          children with the Attention Deficit Hyperactivity Disorder, sleep deprivation
          studies and pharmacological interventions.

    •	    Variability	in	executive	deficits:	Many	neuropsychological	deficits	are	neither	
          absolute or entirely stable (the residual abilities of patients vary from one time
          to another). An important aim in rehabilitation research – and in understanding
          basic function – is to look at factors that are reliably associated with improved
          levels of performance. A series of studies have examined the effect of content
          free cueing (automated reminders for patients to engage in ‘executive reviews’)
          from simple laboratory paradigms through complex multiple-demand tests, to
          real-life activities. The positive effects, as well as having a potentially direct
          therapeutic benefit, are valuable in understanding the level at which these
          common deficits may be operating.

    Work with patient groups can be challenging and it would be expected that successful
    candidates have skills in working with people who may be unwell, distressed or
    disinhibited and in developing relationships with clinical and other services.

    Adrian Owen

    My research combines functional neuroimaging (fMRI, PET, MEG) with neuropsycho-
    logical studies in brain-injured patients. Specific areas of interest include localisation
    of function (‘brain mapping’) within the human frontostriatal system, cognitive deficits
    in patients with Parkinson’s disease (PD) and detecting residual cognitive function in
    the vegetative state and in related disorders of consciousness. For example, our recent
    work on the human frontal lobe has identified an area within the mid-ventrolateral
    frontal cortex that ‘tunes’ the attentional field to represent only the currently relevant
    task information. Our recent fMRI studies of patients with PD have demonstrated that
    the COMT val158met genotype influences frontoparietal activity during planning and
    attention. In addition, we have recently shown, for the first time, that fMRI can reveal
    conscious awareness in patients who are diagnosed as vegetative, when existing
    clinical methods have been unable to provide that information.

    Specific projects include:

    •	    Functional	neuroimaging	studies	of	working	memory	and	other	executive	
          processes in healthy control volunteers;

    •	    Cognitive	deficits	in	Parkinson’s	disease	examined	using	fMRI;


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•	    Executive	control	of	attentional	processes.		Behavioural	studies	and	fMRI;

•	    Investigating	residual	cognitive	function	in	vegetative	state	and	other	disorders		
      of consciousness using neuroimaging.

Natasha Sigala

A quarter of our brain is involved in the sense of vision, which allows us to perceive
the	world	around	us	and	recognize	familiar	objects,	scenes	and	locations	and	dealing	
with new, unfamiliar ones based on their similarity to things we know. Recognition
and	categorization	are	very	similar	processes,	and	both	ask	the	question	“what	is	this	
object?”	To	recognize	an	object	as	a	car,	a	face,	or	an	apple	is	equivalent	to	assigning	
it in the car, face, or apple category. In both cases, the problem is to match
incoming information with information in memory, which contains stored
representations.	Simple	observation	of	the	categorizations	we	make	every	day	shows	
that the same object may belong to a number of categories, depending on the context,
our	experience	with	it,	or	the	purpose	of	the	categorization.	For	example,	an	object	
may	be	categorized	as	a	car,	a	sports	car,	or	a	Ferrari	360	Spider	in	less	than	a	
second.	In	each	of	these	cases	selective	attentional	mechanisms	emphasize	different	
sets of features that support the labelling of the object in more general or more
specific ways, while different brain mechanisms ensure that the most relevant set
of features is highlighted at the appropriate time. We are particularly interested
in the temporal and frontal cortex, and the way these brain areas change their
representations of the world with experience and changing context. We use
psychophysical, electrophysiological, and imaging techniques to ask questions about
how neuronal populations support object representation and multiple task demands,
such	as	attention,	memory	and	categorization.




                                                                                            9
                                          EMOTION

     The central objective of this overall programme of research is to understand the
     nature of the basic cognitive and neural processes that evoke and modify emotion.
     The programme has four more specific research aims related to this central objective:

     •	    To	characterise	the	distinctive	nature	of	affective	representations;	how	other		
           types of information differ from or are integrated with them; and to identify the
           neural systems involved.

     •	    To	increase	theoretical	understanding	of	how	such	representations,	and	
           associated processes, might exacerbate and maintain affective states and
           disorders.

     •	    To	develop	theories	of	how	affective	representations	acquire	their	emotive		 	
           properties and how these representations can be modified.

     •	    To	understand	how	existing	psychological	treatments	for	emotional	disorders		
           achieve their effects, and to design and evaluate improved interventions.

     Individual areas of research:


     Andy Calder

     I am interested in all aspects of face perception, but particularly the neural
     mechanisms underlying the recognition of facial expressions and other social cues
     (e.g.,	eye	gaze).	A	second	aspect	of	my	research	addresses	the	neural	basis	of	human	
     emotions, including anger, disgust, and the role of brain reward systems in eating
     disorders. The research uses a variety of techniques, including patient-based studies,
     functional imaging, and investigations of healthy volunteers. I am particularly
     interested in how individual differences in personality dimensions and genetic
     variants affect the neural correlates of emotion.

     Tim Dalgleish

     The primary interest of my research group is on psychological aspects of traumatic
     stress responses, such as posttraumatic stress disorder (PTSD), and of clinical
     depression. This work involves both children and adults and focuses primarily on
     emotion regulation, cognitive control, autobiographical memory, and reasoning
     and thinking. We also carry out a programme of research on non-clinical volunteer
     participants investigating these same sets of psychological processes. The principal
     methodologies used are cognitive experimental, psychophysiological,
     europsychological and functional imaging. The research programme spans the range
     from basic science to the development of clinical interventions. We have numerous
     ongoing projects that potential PhD students could integrate with, so please get in
     touch if you are interested.

     Barney Dunn

     Our research currently focuses on the consequences of different forms of emotion
     and interpersonal regulation in adult psychopathology, particularly looking at

10
depression and borderline personality disorder. We are investigating whether different
disorders are characterised by the adoption of different ways of controlling emotional
experience and relationships, what the short and long term consequences of these
strategies are, and the extent to which these strategies are influenced by the beliefs
people hold about emotions and relationships. I also work as a clinical psychologist,
so am also interested in developing and evaluating emotion and interpersonal
regulation training approaches as a possible adjunct to existing psychotherapy
approaches (especially in cognitive behaviour therapy and cognitive analytic therapy
models). Other aspects of our research explore the extent to which feedback from the
body is involved in the maintenance of emotion and decision-making symptoms in
psychological disorders and investigate the consequences of self-focused attention in
psychopathology. We use primarily cognitive-experimental, psychophysiological,
functional imaging, questionnaire and clinical interview methodologies, applied to
both clinical and non-clinical populations, to address these questions. Much of our
research is done in collaboration with Tim Dalgleish at the CBSU and with clinical
psychology colleagues at University College London.




                                                                                         11
                                     MEMORY AND KNOWLEDGE

     The aim of this research programme is to develop comprehensive theoretical accounts
     of various aspects of human memory and to explore ways in which these accounts might
     inform, and be informed by, clinical practice and rehabilitation.

     Virtually	all	human	cognitive	behaviour	can	be	viewed	as	relying	on	some	form	of	
     memory, but we focus here on five principal areas:

     •	    The	cognitive	and	neural	architecture	of	semantic	memory;	

     •	    Relationship	between	semantic	memory	and	language,	perception,	and	
           short-term memory;

     •	    The	cognitive	and	neural	basis	of	episodic	memory;

     •	    The	role	of	medial	temporal	lobe	regions	in	human	memory;

     •	    The	neural	bases	of	conscious	and	unconscious	memory.	

     To study these areas, we combine the techniques of Cognitive Neuropsychology (study
     of individuals with memory impairments, e.g., in the context of dementia, encephalitis,
     stroke), Structural Neuroimaging (the use of volumetric measurement techniques to
     assess damage to particular brain structures), Functional Neuroimaging (methods like fMRI
     and MEG/EEG that allow measurement of activity in the brain, both in healthy controls
     and patients, during cognitive processing), Computational Modelling (computer models of
     memory function based on behavioural data) and Cognitive Rehabilitation (working with
     people with brain injury in order to remediate or alleviate cognitive deficits arising from a
     neurological insult).

     Individual areas of research:

     Rik Henson

     This research programme concentrates on multimodal approaches to understanding
     the neural bases of explicit and implicit memory, specifically recollection, familiarity and
     priming. Modalities include functional magnetic resonance imaging (fMRI) and
     electro- and magneto-encephalography (E/MEG). The research concentrates on healthy
     volunteers and the domain of visual object processing, particularly faces. It also entails
     further development of formal methods to integrate fMRI and E/MEG, and more detailed
     computational models that relate these data to neurophysiological data from single-cell
     recording. Possible PhD projects include:

     •	    fMRI	and	EEG	studies	of	recognition	memory,	in	particular	further	attempts	to		          	
           dissociate the neural correlates of familiarity and recollection;

     •	    Detailed	investigations	of	visual	object	priming,	including	tests	of	current	
           models of object and face processing (e.g, with masked priming, split visual-field
           priming and various object transformations);

     •	    Computational	neural	network	models	of	priming	that	relate	haemodynamic,			              	
           electrophysiological, neurophysiological and behavioural data;



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     •	    Methodological	developments	for	the	inverse	problem	for	EEG	and	MEG.	
James Rowe

Characterisation and optimisation of prefrontal cortical functions in health and disease.

Why do you think, act and speak in the way you do? You may have some particular
rewards in mind: money, leisure time, winning etc. There may be ‘rules’ or constraints
on your behaviour because of where you are or who you are with. Genetics and
personality traits may also influence your responses to these rules and rewards.
Based on these factors, your response can still be very variable. It may be to recall
some memory to mind, to choose to speak or move in a particular way, or to engage in
a specific mental process considering what you see and hear or remember.
The functions of the prefrontal cortex remain controversial yet it is critical to the
interactions between such rewards, rules and behaviours. I believe that the functions
of the prefrontal cortex can best be understood in terms of its interactions with other
brain regions, including those regions that affect our sensory perceptions, and those
regions that effect our responses like speech and movement. To understand these
interactions, one can use special methods to measure ‘effective connectivity’ and
‘functional connectivity’ in brain networks. These methods are largely based on
neuroimaging techniques like fMRI and MEG (in our group) or PET and TMS. We have
shown recently for example that following damage to the frontal lobes, the surviving
brain regions may be as active as normal during particular tasks (measured by fMRI)
but that their activity is no longer well coordinated in a regulated network (poor
inter-regional connectivity).

We have been using these methods to understand how rewards affect our choice
of behaviours; how we choose a particular set of rules or actions; and how we
choose between alternative actions when there are no obvious differences in the
outcomes. These processes are of interest to understand normal human behaviour,
but they are directly relevant to understanding the difficulties faced by patients with
neurodegenerative diseases (Frontal lobe dementias, Parkinson’s disease and PSP) or
with structural lesions (tumours/stroke) and to develop rational treatments for these
illnesses. Specific projects would be considered in relation to your specific interests
and skills, and other ongoing projects in the group.




                                                                                          13
                                  SPEECH AND LANGUAGE

     The overall challenge for the development of a cognitive neuroscience of language is
     to relate functional accounts of the language system, behaviourally based and
     cognitively specified, to emerging accounts of the underlying neural system, based
     on neuropsychological and neurobiological inputs. This forms the background for
     the CBSU Speech and Language group’s current research programme, weaving
     together a variety of cross-disciplinary strands. These include (i) research aimed at the
     cortical localisation of language function, ranging from neuropsychological work
     with brain-damaged patients to modern neuro-imaging research (ii) cognitive and
     psycholinguistic behavioural research into the functional structure of the language
     system, incorporating influences from linguistics and from computational
     modelling (iii) psycho-acoustic and acoustic-phonetic research into the basic
     properties of human speech analysis systems, incorporating both behavioral and
     neuro-imaging techniques (iv) insights and constraints derived from the neurobiology
     of the relevant brain systems, and (v) research from a cross-linguistic perspective,
     essential to sort out the general from the particular in the functional and neural
     realisation of any one language system.
     Specific project areas in the Speech and Language Group are listed below (typically
     these involve collaborative research between several Unit scientists):


     •	    Auditory	scene	analysis,	speech	perception,	and	attention,	focused	on	the	
           question of how the listener extracts the speech of a given talker from a back
           ground of other sounds – known as auditory scene analysis (ASA) – and
           investigates the neural basis for ASA and its relation to higher-level cognitive
           processes. This research also provides a basis for the study of ASA in a clinical
           population – users of cochlear implants.

     •	    Neural	and	functional	foundations	of	speech	and	language:	From	speech	to			
           meaning, is concerned with the higher-order functional properties of the
           language system, focussing on speech perception, lexical access and
           representation, and on the deployment of lexical and semantic information
           during on-line interpretation of spoken utterances. We approach this work
           using multiple methods from cognitive neuroscience, including event-related
           fMRI and EEG/MEG studies that investigate the distributed cortical processes
           engaged during spoken language comprehension, computational modelling of
           word recognition, and through a range of behavioural and neuropsychological
           in different patient populations and languages.

     •	    Brain	mechanisms	of	words,	meanings,	and	syntax,	uses	EEG	and	MEG	to	
           address a range of issues in the neurophysiology of language, focusing on the
           spatio-temporal patterns of brain activity elicited by words and sentences,
           studied by the use of multimodal neuroimaging methods.

     •	    Perceptual	learning	and	plasticity	in	spoken	communication,	explores	the	
           formidable capabilities of the human speech perception system for perceptual
           learning and adaptation. We combine behavioural and neuroimaging studies
           to explore the mechanisms by which the perceptual system adjusts to
           phonetically unfamiliar or degraded speech (with a focus on processes likely
           engaged for new users of a cochlear implant), and the neural systems involved
           in initial learning and consolidation of newly-learnt spoken words (with

14
           application to vocabulary acquisition in first and second language learning).
•	    Short-term	memory	systems	and	language,	works	towards	developing	an
      integrated account of the storage and processing of serial order in short-term
      memory and in spoken word-recognition.

Individual areas of research:

Bob Carlyon

Cochlear implant users and people with sensory hearing losses often experience great
difficulty in listening to one person when others are talking at the same time.
In contrast, most normally hearing people are capable of attending to one voice in the
presence of competing speech, even when all the voices present come from the same
location in space (eg: a radio set). In many respects, the surprising thing is not that
impaired listeners have problems with this task, but that normal listeners do so well:
it requires the listener not only to group together the frequency components of the
desired voice, but also to perceptually separate them from other speech sounds with
similar frequency spectra and temporal characteristics. Fortunately, speech, along with
other sounds, contains useful cues which listeners can exploit in order to perform the
appropriate grouping. A possible PhD project would investigate either how normal
listeners process such cues, and/or how one could encode these cues in a cochlear
implant. This latter part of the project would benefit from the specialist hardware and
software for testing implant patients that are available at the CBSU, and from our close
collaboration with Addenbrooke’s hospital. In addition, recent research conducted
jointly with Dr. Friedemann Pulvermuller’s group has used EEG techniques to study the
neurophysiological basis of auditory grouping. Hence the possibilty exists for a student
to undertake a Ph.D. using both auditory and electrophysiological techniques.

Rhodri Cusack

See entry in Attention Group.

Matt Davis

My research is concerned with the cognitive and neural processes involved in
perceiving and understanding spoken and written language. The approach taken is
multi-disciplinary, combining methods from experimental psycholinguistics, functional
neuroimaging (fMRI, MEG/EEG) and computational (connectionist) modelling.
My recent research has sought to characterise processes of learning and adaptation
that alter the way in which spoken stimuli are processed. For instance, repetition
priming experiments have shown rapid and long-lasting changes in neural responses
to primed words that predict the magnitude of behavioural facilitation. Work on the
perception of speech that has been artificially distorted points to processes of
perceptual learning that allow the comprehension of distorted speech to improve
with certain forms of exposure. Finally, neuroimaging studies of vocabulary acquisition
seek to determine the neural correlates of consolidation processes that have been
suggested for newly acquired words. In all this work, a combination of behavioural
and neuroimaging investigations allow a more detailed understanding of
underlying processing mechanisms. This knowledge aims towards functionally and
neuroanatomically-realistic models of processes that are fundamental to powerful and
flexible spoken communication.



                                                                                       15
     Olaf Hauk

     We use a multi-modal imaging approach to problems in the neuroscience of language.
     Although the term “neuroimaging” is usually associated with spatial “maps” or
     “tomographies”, timing information is crucial in order to characterise the processing
     stages at which effects occur. For example, if motor cortex is activated when a subject
     sees or hears the word “kick”, does this mean that this brain area is required in order to
     understand this word, or is it just activated because the subject is actively imagining the
     last time she played football? We address questions like these using electro- and
     magnetoencephalography (EEG/MEG), functional magnetic resonance imaging (fMRI)
     and transcranial magnetic stimulation (TMS). Specific projects address the timing of
     different processing stages in visual word recognition, in particular the neuronal
     representation of words referring to actions, and the role of mirror neurons in action
     word comprehension. We are also interested in developing and evaluating new
     analysis methods. For example, localising brain activity from the surface recordings
     obtained by EEG/MEG requires well-justified modeling assumptions (the “inverse
     problem”). These methods have to be understood theoretically, and tested in
     simulations and systematic experiments.

     William Marslen-Wilson

     Within the general framework of the interdisciplinary study of language as a cognitive,
     computational, and neural system, particular project areas include:

     •	    Speech	input	and	phonological	processing.	What	is	the	nature	of	the	
           transformation undergone by the speech input as it is mapped from early
           auditory analysis through to lexical representations of phonological form and
           the generation of phonological perceptual experience? Techniques involve fMRI
           and EEG, in addition to standard behavioral tasks.

     •	    The	cross-linguistic	mental	lexicon.		This	programme	focuses	on	the	structure		
           (morphology) of lexical representations cross-linguistically, contrasting regular
           and irregular, and combinatorial and non-combinatorial systems. The research
           calls upon behavioural, neuropsychological, neuro-imaging and computational
           techniques.

     •	    Functional	and	neural	architecture	of	the	human	language	system.	The	goal		
           of this research is to integrate research into the functional architecture of the
           human language system with neuropsychological and neuro-imaging studies of
           its underlying neural architecture. Specific questions concern the way in which
           different types of linguistic knowledge are organised as a processing system,
           whether there are modality specificities in the representation and access of
           linguistic knowledge, and the underlying computational properties of these
           systems.

     Dennis Norris

     A major theme running through much of the research on spoken word recognition
     conducted at the Unit in recent years has been the problem of recognising words in
     continuous speech. In contrast to written language, where there are white spaces
     between the words, spoken language contains few reliable cues to the location of word
     boundaries. How do listeners solve the problem of recognising spoken words without

16
first knowing where the words actually are in the input? We have been tackling this,
and related problems in spoken word recognition by a mixture of conventional
experimental work, both on English and on other languages with contrasting
phonological properties, and by the development of a large scale connectionist model
of spoken word recognition. Other work concentrates on understanding how spoken
words are represented in the mental lexicon and on the issue of whether lexical
information can influence the processing of sub-lexical units such as phonemes. PhD
work in this area would involve experimental work on spoken word recognition but
could also involve computational modelling. We are currently developing a new
connectionist model of word recognition and vocabulary acquisition.

A second programme studies short term memory and the relation between
short- and long-term memory. Most of this work focuses on memory for serial order in
short-term memory, and on how short-term memory contributes to long-term learning.
Much of the experimental work is driven by computational models of short-term
memory (Page and Norris, 1999). The computational work continues to generate a
range of experimental predictions which could form the starting point for a PhD. The
PhD could itself include computational work to extend the scope of the model.

Finally we are interested in building on the work in both speech and memory to
develop a better understanding of both the memory systems underpinning language
use, and the way in which the requirements of language have shaped the memory
systems themselves.

Friedemann Pulvermüller

Research centers around the question “What are the brain mechanisms of language?”
A neurobiological framework is used to generate hypotheses about neuron circuits
that form the putative organic basis of language elements, such as words and syntactic
rules. Based on these hypotheses, neuroimaging and neuropsychological work is
carried out. Emphasis is put on fast neurophysiological techniques, in particular EEG
and MEG, which allow us to follow the exact spatio-temporal pattern of neuronal
activity underlying fast language processes. At present, the following projects are
being studied:

•	    Brain	activity	reflecting	word	processing;

•	    Word-category-specific	deficits	after	brain	damage;	

•	    The	role	of	attention	in	speech	processing;	

•	    Brain	mechanisms	of	serial	order	and	syntax;	

•	    Language	rehabilitation;	

•	    Brain	models	of	language;	

Most of this research will be continued together with Olaf Hauk and Yury Shtyrov in
the Cognition and Brain Sciences Unit’s EEG and MEG laboratories.




                                                                                       17
     Yury Shtyrov

     Our research is concentrated on the brain’s mechanisms of speech and language
     processing. It is particularly focussed on studying automatic aspects of the cerebral
     language processing, i.e. those taking place outside the focus of voluntary attention.
     For better understanding of spatio-temporal dynamics of such processing,
     neuroimaging of language function in the brain is carried out using various modern
     techniques; special attention is given to methods with high temporal and increasingly
     improving spatial resolution (MEG, EEG). Recent and ongoing projects include
     research on neural memory traces for individual words, automatic syntax and
     semantic processing in the brain, word-category specific brain processes, interaction
     of language processing and attention. These can be grouped into four general topics:

     •	    Automatic	semantic	processing	in	the	human	brain.	

     •	    Automatic	grammar	processing	in	the	human	brain.	

     •	    Interactions	between	automatic	and	attention-dependent	processes	in	the	brain

     •	    Mechanisms	of	hemispheric	asymmetry	of	the	language	function	in	the	brain.


     Most of this research is done in the Cognition and Brain Sciences Unit’s MEG, EEG
     and	fMRI	laboratories	in	cooperation	with	Prof	Friedemann	Pulvermüller,	Dr.	Olaf	
     Hauk, Prof. William Marslen-Wilson and other CBSU scientists. Further MEG and EEG
     work is carried out in collaboration with the University of Helsinki, Finland, and fMRI
     can also be done at the Wolfson Brain Imaging Centre (WBIC) in Cambridge.
     A number of smaller-scale collaborative projects with other groups both within and
     outside the Unit are also carried out.

     Sami Boudelaa

     I am interested in the cross-linguistic aspect of the mental lexicon with a special
     focus on the contrast between the Semitic and Indo-European lexical systems
     as exemplified by Arabic and English respectively. The question I address, in
     collaboration with colleagues at the CBU, using behavioural and neuro-imaging
     techniques, concern the implications of (a) the cross-linguistic differences in terms
     of morphological regularity and irregularity and (b) the combinatorial and
     non-combinatorial processes of lexical processing and representation. PhD work
     within this project will involve behavioural and imaging research into spoken and
     written language in normal and patient populations, and could also involve modelling.




18
                                        METHODS

Many of the recent advances in cognitive neuroscience are owed to new technological
developments. This area is constantly evolving, bringing new challenges and
opportunities. Applications for postgraduate students from numerate disciplines
to work in this field are most welcome.

On site at the CBSU are a 3 Tesla Siemens MRI scanner, which images the blood
response to brain activity, a 306 channel MEG machine, which measures the weak
magnetic fields generated by the electric currents of the brain, and a 65-channel EEG lab,
which records electric potentials on the scalp surface. There is constant development to
extract new kinds of information from these data, to evaluate the performance of existing
methods, and to make these measurements more accurate. This is an interdisciplinary
approach undertaken both by scientists dedicated to methodological development, and
by a broad range of researchers with a background in neuroscience, psychology and
medicine, for example.

One of the major challenges lies in data analysis. Both MRI and MEG/EEG datasets
undergo a number of intricate spatial & temporal transformations to remove artefacts,
and are subject to involved statistical analyses to tease apart and characterise different
components of brain activity.

Applications from postgraduate students that can contribute to this work are most
welcome. Some examples of previous and current work are:

•	    Combining	information	from	different	imaging	modalities,	e.g.	spatial	
      information from fMRI with temporal information from MEG/EEG

•	    Real-time	analysis	of	MRI	data

•	    The	localisation	of	the	neural	sources	of	the	magnetic	signals	recorded	
      with MEG/EEG

•	    Extracting	and	localising	information	about	oscillatory	brain	activity	from	
      MEG/EEG data

•	    Understanding	distributed	patterns	of	brain	activity,	e.g.	using	multivariate	
      pattern recognition methods, coherence analysis or dynamic causal modeling

•	    Correcting	distortions	in	MRI	data	using	maps	of	magnetic	field	errors	

To work on either acquisition or analysis, you should have a background perhaps in
Physics, Computer Science, Engineering or Maths. Knowledge of neuroscience or
psychology is not required but might be helpful. You should be familiar with at least one
programming language, such as Matlab, C++ or Python. Enthusiasm to work in an
interdisciplinary team is essential.

You will benefit from the broad range of methodological expertise at the CBU,
great demand for new techniques, and tight integration of methods research with
neuroscientific applications. We have regular seminars and meetings of interest groups,
which also involve collaborators from other institutes in Cambridge. Convenient access
to neuroimaging facilities and a powerful computing cluster is available. For more

                                                                                             19
information on Methods, please contact Rhodri Cusack.
 Our Work And Study Opportunities – More Information

 For more information on any aspect of our work and study opportunities, please visit
 our website http://www.mrc-cbu.cam.ac.uk/ where you can find much more detail on
 our researchers, their current topics and publications, and life at the CBSU generally.
 Informal approaches to our scientific staff are welcomed, from prospective students
 or anyone interested in working with us. Full contact details can be found on the
 website or for a general enquiry just email info@mrc-cbu.cam.ac.uk.


                                       APPENDIX

            CBSU PROCEDURE FOR POSTGRADUATE STUDENTS

 In recent years there has been much concern nationally over PhD students taking
 more than three years to complete their degree. The CBSU has, therefore, developed
 a procedure designed to ensure that students complete their research on time.

 The primary goal of the student’s first year is to put them in a position to “hit the
 ground running” at the beginning of their second year, with a fully developed and
 agreed research plan for the last two years of their thesis, and, preferably, with a
 significant chunk of relevant research and training already completed. To this end,
 students and supervisors are encouraged to begin discussion of possible topics as
 soon as the student arrives, and to initiate exploratory research, skills training,
 literature surveys, etc., as soon as is practicable. If supervisors do not feel that
 satisfactory progress has been made towards agreeing and developing a possible
 topic within six months of the student arriving (usually March 1st of the first year),
 then they should allocate a topic within the broad area of interest stated on the
 student’s application. A student who objects to the proposed topic may approach
 the Graduate Studies Committee over a change in supervisor, but should be prepared
 to accept a proposal from the secondary supervisor.

 A decision on whether to register the student for the PhD degree is made at the end of
 the first year, when they are required to submit a 5000 word report by 30th June.
 This will comprise a summary of the student’s progress over the previous months
 and is likely to include a literature review motivating the choice of research topic and
 an account of experimental and theoretical work completed. The report must also
 include a proposal outlining the research planned for the next two years’ work,
 directed towards the completion of a PhD in that period. The student will also be
 expected to submit an up-to-date Progress Log, outlining their participation in
 seminars, training courses, etc., over the first year. This is to meet University and
 Medical Research Council requirements for graduate training. A minimum of 60
 credits is required for transferable skills training over the three year period, although
 it is likely that a significant proportion will be gained in the first year. Students are
 encouraged to attend courses available elsewhere, in particular those provided by the
 University of Cambridge Graduate School of Life Sciences (of which students are part).
 Some examples of credit scores can be found on their Website:

 http://www.bio.cam.ac.uk/gradschool/current/courses/credits.html




21
The report is distributed to and evaluated by the secondary supervisor and by
the Graduate Tutors, and a four way meeting is then held with the student.
A recommendation would normally then be made to the Faculty Degree Committee
that the student be registered for a PhD and (where applicable) to the MRC that the
grant be continued for a further two years. These recommendations can only be made
following the meeting with the Graduate Committee, and it is the supervisor’s
esponsibility to ensure that these occur on a reasonable time-scale, and unless there
are exceptional circumstances, we would expect the evaluation process to be
completed by the end of July.

At the time of the first year assessment the student will also meet with the Pastoral
Tutors to talk through any issues that may have arisen. The student should not,
however, wait until this formal meeting if they have anything they want to discuss.
The Pastoral Tutors are there to help at any time.

Around 9 months before students are due to complete, a meeting will be held between
student, supervisors, and representatives from the Graduate Committee to make sure
things are on track for completion. The aim of this meeting is to ensure adequate
planning – and hence minimal stress – for the third year. Students will be asked to
bring two things to this meeting: an outline of the proposed thesis, with a plan for
what is still needed and when it will be done; and a first part of the thesis itself, which
could be literature review, methods sections, an experimental chapter, etc.

This is not intended as an assessment, which in any case would not be suitable in
a student’s third year. The thesis plan is intended to crystallise the remaining
requirements in the minds of both student and supervisors. The written material is
intended to ensure that the student has actually got some experience of what
writing the thesis will be like. Students very often discover that writing is far more
time-consuming than they had expected, and one goal of this meeting is to ensure
realistic expectations in this regard.

For more on any aspect of our work and study opportunities, please visit our website
http://www.mrc-cbu.cam.ac.uk/ where you can find much more information.
HERE IS WHAT SOME OF OUR PHD
STUDENTS HAVE TO SAY ABOUT THE UNIT:



  I am a first year PhD student working in the
  Speech and Language group here at the Unit,
  and have found it a very supportive and
  enjoyable place to work and study. There is
  nothing nicer than walking, on a lovely
  summer’s day, through the garden to the
  on-site MRI scanner building to carry out
  your research.




  The CBSU has been a great place to study, and
  the people who work here have created an
  atmosphere that is intellectually stimulating,
  but also extremely friendly and supportive.
  I	was	amazed	at	the	technical	resources	that	
  were available to me as a graduate student,
  including the kind of access to techniques like
  fMRI that I could only have dreamt of before I
  started!	Even	more	than	that,	I	was	amazed	at	
  the wealth of knowledge and experience that
  was available, and the number of extremely
  talented people who seemed perfectly happy
  to be bothered with rather basic questions at a
  moment’s notice.
The Unit provides a unique mix of academic and
social elements which make it a great place to
do a Ph.D. It does this through providing an
excellent arena in which to absorb and contribute
to cutting edge research.




Very	friendly	environment,	excellent	research	
support, stimulating team work - a very
enjoyable group of people. Particularly, I am
still	amazed	at	how	accessible	everyone	at	the	
Unit really is - you can just knock at their door
and, if they are there, they will listen to you
and help you if they can.




“The CBU is a really friendly and supportive
environment in which to pursue a PhD, with
great facilities and very friendly enviorment.
Cognition and Brain Sciences Unit, Cambridge

             Graduate Studies

   email: grad-admin@mrc-cbu.cam.ac.uk

      http://www.mrc-cbu.cam.ac.uk

				
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