Adeen Flinker

Gender bias in academia: A lifetime problem that needs solutions

Summary:

Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers’ lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society.

Authors:

  • Anaïs Llorens

  • Athina Tzovara

  • Ludovic Bellier

  • Ilina Bhaya-Grossman

  • Aurélie Bidet-Caulet

  • William K Chang

  • Zachariah R Cross

  • Rosa Dominguez-Faus

  • Adeen Flinker

  • Yvonne Fonken

  • Mark A Gorenstein

  • Chris Holdgraf

  • Colin W Hoy

  • Maria V Ivanova

  • Richard T Jimenez

  • Soyeon Jun

  • Julia WY Kam

  • Celeste Kidd

  • Enitan Marcelle

  • Deborah Marciano

  • Stephanie Martin

  • Nicholas E Myers

  • Karita Ojala

  • Anat Perry

  • Pedro Pinheiro-Chagas

  • Stephanie K Riès

  • Ignacio Saez

  • Ivan Skelin

  • Katarina Slama

  • Brooke Staveland

  • Danielle S Bassett

  • Elizabeth A Buffalo

  • Adrienne L Fairhall

  • Nancy J Kopell

  • Laura J Kray

  • Jack J Lin

  • Anna C Nobre

  • Dylan Riley

  • Anne-Kristin Solbakk

  • Joni D Wallis

  • Xiao-Jing Wang

  • Shlomit Yuval-Greenberg

  • Sabine Kastner

  • Robert T Knight

  • Nina F Dronkers

Date: 2021

DOI: https://doi.org/10.1016/j.neuron.2021.06.002

View PDF


iEEG-BIDS, extending the Brain Imaging Data Structure specification to human intracranial electrophysiology

Description:

The Brain Imaging Data Structure (BIDS) is a community-driven specification for organizing neuroscience data and metadata with the aim to make datasets more transparent, reusable, and reproducible. Intracranial electroencephalography (iEEG) data offer a unique combination of high spatial and temporal resolution measurements of the living human brain. To improve internal (re) use and external sharing of these unique data, we present a specification for storing and sharing iEEG data: iEEG-BIDS.

Authors:

  • Christopher Holdgraf

  • Stefan Appelhoff

  • Stephan Bickel

  • Kristofer Bouchard

  • Sasha D’Ambrosio

  • Olivier David

  • Orrin Devinsky

  • Benjamin Dichter

  • Adeen Flinker

  • Brett L. Foster

  • Krzysztof J. Gorgolewski

  • Iris Groen

  • David Groppe

  • Aysegul Gunduz

  • Liberty Hamilton

  • Christopher J. Honey

  • Mainak Jas

  • Robert T. Knight

  • Jean-Philippe Lachaux

  • Jonathan C. Lau

  • Christopher Lee-Messer

  • Brian N. Lundstrom

  • Kai J. Miller

  • Jeffrey G. Ojemann

  • Robert Oostenveld

  • Natalia Petridou

  • Gio Piantoni

  • Andrea Pigorini

  • Nader Pouratian

  • Nick F. Ramsey

  • Arjen Stolk

  • Nicole C. Swann

  • François Tadel

  • Bradley Voytek

  • Brian A . Wandell

  • Jonathan Winawer

  • Kirstie Whitaker

  • Lyuba Zehl

  • Dora Hermes

Date: 2019

DOI: https://doi.org/10.1038/s41597-019-0105-7

View PDF


Intracranial electrophysiology in language research

ABSTRACT

Intracranial electrophysiological recording in humans has been a long standing technique in neurosurgical treatment for epilepsy and have served as an important window in to how the human brain processes language. This chapter is aimed to introduce the reader to the technique, how it historically contributed to language mapping, its advantages and disadvantages as a research tool, and analysis techniques that have provided novel findings and approaches in the area of language processing.


AUTHORS

  • Adeen Flinker

  • Vitória Piai

  • Robert T. Knight

Date: 2018

View PDF


Differential Sources for 2 Neural Signatures of Target Detection: An Electrocorticography Study

ABSTRACT

Electrophysiology and neuroimaging provide conflicting evidence for the neural contributions to target detection. Scalp electroencephalography (EEG) studies localize the P3b event-related potential component mainly to parietal cortex, whereas neuroimaging studies report activations in both frontal and parietal cortices. We addressed this discrepancy by examining the sources that generate the target-detection process using electrocorticography (ECoG). We recorded ECoG activity from cortex in 14 patients undergoing epilepsy monitoring, as they performed an auditory or visual target-detection task. We examined target-related responses in 2 domains: high frequency band (HFB) activity and the P3b. Across tasks, we observed a greater proportion of electrodes that showed target-specific HFB power relative to P3b over frontal cortex, but their proportions over parietal cortex were comparable. Notably, there was minimal overlap in the electrodes that showed target-specific HFB and P3b activity. These results revealed that the target-detection process is characterized by at least 2 different neural markers with distinct cortical distributions. Our findings suggest that separate neural mechanisms are driving the differential patterns of activity observed in scalp EEG and neuroimaging studies, with the P3b reflecting EEG findings and HFB activity reflecting neuroimaging findings, highlighting the notion that target detection is not a unitary phenomenon.





AUTHORS

  • Julia W. Y. Kam

  • Sara Szczepanski

  • Ryan T. Canolty

  • Adeen Flinker

  • Kurtis I. Auguste

  • Nathan E. Crone

  • Heidi E. Kirsch

  • Rachel A. Kuperman

  • Jack J. Lin

  • Josef Parvizi

  • Robert T. Knight

Date: 2016

DOI: 10.1093/cercor/bhw343

View PDF


A Cool Approach to Probing Speech Cortex

ABSTRACT

In this issue of Neuron, Long et al. (2016) employ a novel technique of intraoperative cortical cooling in humans during speech production. They demonstrate that cooling Broca’s area interferes with speech timing but not speech quality.




AUTHORS

  • Adeen Flinker

  • Robert T. Knight

Date: 2016

DOI: 10.1016/j.neuron.2016.02.039

View PDF


Redefining the role of Broca’s area in speech

Authors:

  • Adeen Flinker

  • Anna Korzeniewska

  • Avgusta Shestyuk

  • Piotr Franaszczuk

  • Nina F. Dronkers

  • Robert T. Knight

  • Nathan E. Crone

Date: 2015

DOI: 10.1073/pnas.1414491112

View PDF

Abstract:

For over a century neuroscientists have debated the dynamics by which human cortical language networks allow words to be spoken. Although it is widely accepted that Broca’s area in the left inferior frontal gyrus plays an important role in this process, it was not possible, until recently, to detail the timing of its recruitment relative to other language areas, nor how it interacts with these areas during word production. Using direct cortical surface recordings in neurosurgical patients, we studied the evolution of activity in cortical neuronal populations, as well as the Granger causal interactions between them. We found that, during the cued production of words, a temporal cascade of neural activity proceeds from sensory representations of words in temporal cortex to their corresponding articulatory gestures in motor cortex. Broca’s area mediates this cascade through reciprocal interactions with temporal and frontal motor regions. Contrary to classic notions of the role of Broca’s area in speech, while motor cortex is activated during spoken responses, Broca’s area is surprisingly silent. Moreover, when novel strings of articulatory gestures must be produced in response to non- word stimuli, neural activity is enhanced in Broca’s area, but not in motor cortex. These unique data provide evidence that Broca’s area coordinates the transformation of information across large-scale cortical networks involved in spoken word production. In this role, Broca’s area formulates an appropriate articulatory code to be implemented by motor cortex.

Reconstructing Speech from Human Auditory Cortex

Authors:

  • Brian Pasley

  • Stephen V. David

  • Nima Mesgarani

  • Adeen Flinker

  • Shihab A. Shamma

  • Nathan E. Crone

  • Robert T. Knight

  • Edward F. Chang

Date: 2012

DOI: 10.1371/journal.pbio.1001251

PubMed: 22303281

View PDF

Abstract:

How the human auditory system extracts perceptually relevant acoustic features of speech is unknown. To address this question, we used intracranial recordings from nonprimary auditory cortex in the human superior temporal gyrus to determine what acoustic information in speech sounds can be reconstructed from population neural activity. We found that slow and intermediate temporal fluctuations, such as those corresponding to syllable rate, were accurately reconstructed using a linear model based on the auditory spectrogram. However, reconstruction of fast temporal fluctuations, such as syllable onsets and offsets, required a nonlinear sound representation based on temporal modulation energy. Reconstruction accuracy was highest within the range of spectro-temporal fluctuations that have been found to be critical for speech intelligibility. The decoded speech representations allowed readout and identification of individual words directly from brain activity during single trial sound presentations. These findings reveal neural encoding mechanisms of speech acoustic parameters in higher order human auditory cortex.

Single-trial speech suppression of auditory cortex activity in humans.

Authors:

  • Adeen Flinker

  • Edward F. Chang

  • Heidi E. Kirsch

  • Nicholas M. Barbaro

  • Nathan E. Crone

  • Robert T. Knight

Date: 2010

PubMed: 21148003

View PDF

Abstract:

The human auditory cortex is engaged in monitoring the speech of interlocutors as well as self-generated speech. During vocalization, auditory cortex activity is reported to be suppressed, an effect often attributed to the influence of an efference copy from motor cortex. Single-unit studies in non-human primates have demonstrated a rich dynamic range of single-trial auditory responses to self-speech consisting of suppressed, nonsuppressed and excited auditory neurons. However, human research using noninvasive methods has only reported suppression of averaged auditory cortex responses to self-generated speech. We addressed this discrepancy by recording electrocorticographic activity from neurosurgical subjects performing auditory repetition tasks. We observed that the degree of suppression varied across different regions of auditory cortex, revealing a variety of suppressed and nonsuppressed responses during vocalization. Importantly, single-trial high-gamma power (γ(High), 70-150 Hz) robustly tracked individual auditory events and exhibited stable responses across trials for suppressed and nonsuppressed regions.

Sub-centimeter language organization in the human temporal lobe

Authors:

  • Adeen Flinker

  • Edward F. Chang

  • Nicholas M. Barbaro

  • Mitchel S. Berger

  • Robert T. Knight

Date: 2010

DOI: 10.1016/j.bandl.2010.09.009

PubMed: 20961611

View PDF

Abstract:

The human temporal lobe is well known to be critical for language comprehension. Previous physiological research has focused mainly on non-invasive neuroimaging and electrophysiological techniques with each approach requiring averaging across many trials and subjects. The results of these studies have implicated extended anatomical regions in peri-sylvian cortex in speech perception. These non-invasive studies typically report a spatially homogenous functional pattern of activity across several centimeters of cortex. We examined the spatiotemporal dynamics of word processing using electrophysiological signals acquired from high-density electrode arrays (4mm spacing) placed directly on the human temporal lobe. Electrocorticographic (ECoG) activity revealed a rich mosaic of language activity, which was functionally distinct at four mm separation. Cortical sites responding specifically to word and not phoneme stimuli were surrounded by sites that responded to both words and phonemes. Other sub-regions of the temporal lobe responded robustly to self-produced speech and minimally to external stimuli while surrounding sites at 4mm distance exhibited an inverse pattern of activation. These data provide evidence for temporal lobe specificity to words as well as self-produced speech. Furthermore, the results provide evidence that cortical processing in the temporal lobe is not spatially homogenous over centimeters of cortex. Rather, language processing is supported by independent and spatially distinct functional sub-regions of cortex at a resolution of at least 4mm.