11 Aug 2016
August 11, 2016

Defending a Late Colleague

In The News

New book criticizing a well-known professor of neuroscience at MIT who died this year sparks ire and an unusual public response from her colleagues.  Inside Higher Ed (Aug 11, 2016)

Yes, we do.  And over 200 neuroscientists from around the world have signed a letter to the NY Times supporting Sue and condemming the NY Times article.

Read about it here:  STAT: MIT challenges New York Times over book on famous brain patient


In the article “The Brain That Couldn’t Remember,” written by Luke Dittrich and appearing on the New York Times website on August 3 and in the Times Magazine on August 7, three allegations are made against Professor Suzanne Corkin, who died on May 24. Professors John Gabrieli and Nancy Kanwisher at MIT have examined evidence in relation to each allegation, and, as detailed below, have found significant evidence that contradicts each allegation. In our judgment, the evidence below rebuts each claim.

1. Allegation that research records were or would be destroyed or shredded.
We believe that no records were destroyed and, to the contrary, that Professor Corkin worked in her final days to organize and preserve all records. Even as her health failed (she had advanced cancer and was receiving chemotherapy), she instructed her assistant to continue to organize, label, and maintain all records related to Henry Molaison. The records currently remain within our department.

Assuming that the interview is accurately and fully reported by Mr. Dittrich, we cannot explain why Professor Corkin made the comments reported in the article. This may have been related to tensions between the author and Professor Corkin because she had turned down his request to examine Mr. Molaison’s confidential medical and research records.

Regardless, the critical point is not what was said in an interview, but rather what actions were actually taken by Professor Corkin. The actions were to preserve the records.

2. Allegation that the finding of an additional lesion in left orbitofrontal cortex was suppressed.
The public record is clear that Professor Corkin communicated this discovery of an additional lesion in Mr. Molaison to both scientific and public audiences. This factual evidence is contradictory to any allegation of the suppression of a finding.

The original scientific report (Nature Communications, 2014) of the post-mortem examination of Mr. Molaison’s brain included this information in the most prominent and widely read portion of the report, the abstract.

In addition, Professor Corkin herself disseminated this information in public forums, including a 2014 interview, posted on MIT News and subsequently elsewhere online, in which she said: “We discovered a new lesion in the lateral orbital gyrus of the left frontal lobe. This damage was also visible in the postmortem MRI scans. The etiology of this lesion is presently unknown; future histological studies will clarify the cause and timeframe of this damage. Currently, it is unclear whether this lesion had any consequence for H.M.’s behavior.”

3. Allegation that there was something inappropriate in the selection of Tom Mooney as Henry’s guardian.
In her book “Permanent Present Tense” (2013), Professor Corkin describes precisely the provenance of Mr. Molaison’s guardianship (page 201).

Briefly, in 1974 Mr. Molaison and his mother (who was in failing health; his father was deceased) moved in with Lillian Herrick, whose first husband was related to Mr. Molaison’s mother. Mrs. Herrick is described as caring for Mr. Molaison until 1980, when she was diagnosed with advanced cancer, and Mr. Molaison was admitted to a nursing home founded by her brother.

In 1991, the Probate Court in Windsor Locks, Connecticut, appointed Mrs. Herrick’s son, Tom Mooney, as Mr. Molaison’s conservator (Mr. Mooney is referred to as “Mr. M” in the book because of his desire for privacy.) This family took an active interest in helping Mr. Molaison and his mother, and was able to help place him in the nursing home that took care of him.

Mr. Dittrich provides no evidence that anything untoward occurred, and we are not aware of anything untoward in this process. Mr. Dittrich identifies some individuals who were genetically closer to Mr. Molaison than Mrs. Herrick or her son, but it is our understanding that this family took in Mr. Molaison and his mother, and took care of Mr. Molaison for many years. Mr. Mooney was appointed conservator by the local court after a valid legal process, which included providing notice of a hearing and appointment of counsel to Mr. Molaison.

Journalists are absolutely correct to hold scientists to very high standards. I — and over 200 scientists who have signed a letter to the editor in support of Professor Corkin — believe she more than achieved those high standards. However, the author (and, implicitly, the Times) have failed to do so.

James J. DiCarlo MD, PhD
Peter de Florez Professor of Neuroscience
Head, Department of Brain and Cognitive Sciences
Investigator, McGovern Institute for Brain Research
Massachusetts Institute of Technology

Read it on the Dept of Brain and Cognitive Sciences website

A Tale of Science, Ethics, Intrigue, and Human Flaws

Over 200 scientists have signed a letter to the New York Times (below) supporting Sue and condemning the article.  It is a biased and unfair attack on someone who is no longer here to defend herself.

Detailed response from MIT.
MIT News: Faculty at MIT and beyond respond forcefully to an article critical of Suzanne Corkin

News article
STAT: MIT challenges New York Times over book on famous brain patient

Original statement (signed by over 200 neuroscientists):

We are a community of scientists who are disturbed by a recent New York Times Magazine article (“The Brain That Couldn’t Remember”), which describes Professor Suzanne Corkin’s research in what we believe are biased and misleading ways. A number of complex issues that occur in research with humans, from differing interpretations of data among collaborators to the proper disposition of confidential data, are presented in a way so as to call into question Professor Suzanne Corkin’s integrity. These assertions are contrary to everything we have known about her as a scientist, colleague, and friend.  Professor Corkin dedicated her life to using the methods of neuropsychology to illuminate how the brain gives rise to the mind, especially how different regions of the human brain support different aspects of memory. Her scientific contributions went far beyond her work with the amnesic patient HM (whose well being she protected for decades), with major contributions to understanding clinical disorders such as Alzheimer’s and Parkinson’s disease. She was a highly accomplished scientist, an inspiring teacher, a beloved mentor to students and faculty, and a champion of women in science.  While her recent passing is a great loss to our field, her passion and commitment continue to inspire all of us. We only regret that she is not able to respond herself.

Nice review and test of a hypothesis about the role of transient beta oscillations in cortical processing.

Sherman et al (2016) Neural mechanisms of transient neocortical beta rhythms: Converging evidence from humans, computational modeling, monkeys, and mice

For much of the history of modern neuroscience, it has been a assumed that the neuron is the functional unit of the brain.  But now there is increasing evidence that ensembles of neurons, not individuals, are the functional units.  One line of evidence is that many neurons in higher cortical areas have “mixed selectivity” , responses to diverse combinations of variables; they don’t signal one “message”.  Thus, their activity only makes sense when simultaneously considering the activity of other neurons.  In fact, we (Rigotti et al., 2013; Fusi et al., 2016) have shown that mixed selectivity gives the brain the computational horsepower needed for complex behavior.

In this paper, Dehaqani et al show that simultaneously recorded prefrontal cortex neurons have high-dimensional, mixed-selectivity, representations and convey more information as a population than even individuals.  This was especially true for parts of visual space that were weakly encoded by single neurons.  Less-informative neurons were recruited into ensemble to fully encode visual space.

Prefrontal neurons expand their representation of space by increase in dimensionality and decrease in noise correlation.  Mohammad-Reza Dehaqani, Abdol-Hossein Vahabie, Mohammadbagher Parsa, Behrad Noudoost, Alireza Soltani
doi: http://dx.doi.org/10.1101/065581

Further reading:
Fusi, S., Miller, E.K., and Rigotti, M. (2016) Why neurons mix: High dimensionality for higher cognition.  Current Opinion in Neurobiology. 37:66-74  doi:10.1016/j.conb.2016.01.010. View PDF »

Rigotti, M., Barak, O., Warden, M.R., Wang, X., Daw, N.D., Miller, E.K., & Fusi, S. (2013) The importance of mixed selectivity in complex cognitive tasks. Nature, 497, 585-590, doi:10.1038/nature12160. View PDF »

Yuste, Rafael. “From the neuron doctrine to neural networks.” Nature Reviews Neuroscience 16.8 (2015): 487-497.

Woolgar et al provide a meta-analysis of experiments using multivoxel pattern analysis in FMRI.  They show that cortical areas traditionally though to be visual, auditory or motor, primarily (though not exclusively) code visual, auditory, and motor information.  However, the frontoparietal cortex is hypothesized to a multiple-demand network and it shows domain generality, coding multisensory and rule information.

Woolgar, Alexandra, Jade Jackson, and John Duncan. “Coding of visual, auditory, rule, and response information in the brain: 10 years of multivoxel pattern analysis.” Journal of cognitive neuroscience (2016).

LIP has been the area for studying motion direction discrimination as model of decision-making.  In this paper, Katz et al show that deactivation of LIP has little effect on that model task.  Deactivating an upstream area, MT, where decision signals are weaker, however, caused a big deficit.

Dissociated functional significance of decision-related activity in the primate dorsal stream.  Leor N. Katz, Jacob L. Yates, Jonathan W. Pillow & Alexander C. Huk  Nature.

Sure, this is a cautionary tale of correlates does not equal causation.  But it is important not to over-interpret the results of lesions/deactivations.  They identify *bottlenecks* in neural processing, not contributions.  Just because there is no effect of deactivation doesn’t mean that a given area doesn’t contribute.  MT could be providing the raw materials that a number of downstream areas, including LIP, use for decision-making.   This doesn’t mean that LIP doesn’t contribute to decisions, it just means that it is not the only area that contributes.

This is in line with recent work showing that neural processing is more distributed than previously thought.  For example, see:
Siegel, M., Buschman, T.J., and Miller, E.K. (2015) Cortical information flow during flexible sensorimotor decisions.  Science. 19 June 2015: 1352-1355. View PDF »




An excellent, comprehensive review of the neurobiology of decision-making by David Freedman and John Asaad.

Neuronal Mechanisms of Visual Categorization: An Abstract View on Decision Making
David J. Freedman and John A. Assad, Annual Review of Neuroscience, 2016
DOI: 10.1146/annurev-neuro-071714-033919