The Miller Lab @ MIT

  • Multifaceted roles for low-frequency oscillations

    Miller Lab

    Ekstrom and Watrous review the role of low frequency oscillatory coupling in cognition.  The propose that different  resonant frequencies within the same networks support movement vs memory related functions.  They provide further evidence and argument for a role for oscillatory coupling in multiplexing of function.  In other words, different frequency coupling can allow the same networks to have different roles by allowing them to communicate different messages to different targets.

    Miller Lab work on oscillatory coupling and multiplexing:
    Buschman, T.J. and Miller, E.K. (2007) Top-down versus bottom-up control of attention in the prefrontal and posterior parietal cortices. Science. 315: 1860-1862   View PDF »

    Miller, E.K. and Buschman, T.J. (2013) Cortical circuits for the control of attention.  Current Opinion in Neurobiology.  23:216–222  View PDF »

  • Neuronal correlates of a visual “sense of number”

    Miller Lab
    , ,

    Miller Lab alumnus, Andreas Nieder, shows number tuned neurons in pefrontal and parietal cortices of naive (untrained) subjects.
    Viswanathan and Nieder 2013

    Andreas Nieder’s Miller Lab work on the neural substrates for numerosity:

    Nieder, A., Freedman, D.J., and Miller, E.K. (2002) Representation of the quantity of visual items in the primate prefrontal cortex.  Science. 297:1708-1711. View PDF »

    Nieder, A. and Miller, E.K. (2003) Coding of cognitive magnitude: Compressed scaling of numerical information in the primate prefrontal cortex. Neuron. 37:149-157. View PDF »

    Nieder, A. and Miller, E.K. (2004) A parieto-frontal network for visual numerical information in the monkey. Proceedings of the National Academy of Sciences, 101:7457-7462. View PDF »

    Nieder, A. and Miller, E.K. (2004) Analog numerical representations in rhesus monkeys: Evidence for parallel processing. Journal of Cognitive Neuroscience. 16:889-901. View PDF »

  • Brain blast: DIY electrical brain stimulation

    Miller Lab
    , ,

    DIY attempts at electrical brain stimulation to improve cognition are to get easier. Nature editorial.

  • Psychedelic mushrooms decrease cortical alpha-band oscillations

    Miller Lab

    Kometer et al show that psilocybin decreased spontaneous alpha oscillations which precluded the usual decrease in alpha when a visual stimulus is presented.  Psilocybin may result in a brain state in which normal stimulus-driven cortical excitation is overwhelmed by spontaneous neuronal excitation resulting in altered perception and hallucinations.

    We recently found evidence that alpha oscillations are useful for clearing out unwanted thoughts (neural ensembles) that could interfere with the current cognitive demands:

    • Buschman, T.J., Denovellis, E.L., Diogo, C., Bullock, D. and Miller, E.K. (2012) Synchronous oscillatory neural ensembles for rules in the prefrontal cortex. Neuron, 76: 838-846.  View PDF

  • Dissociable dopaminergic control of saccadic target selection

    Miller Lab

    Soltani et al (2013) explored the role of D1 and D2 dopamine receptors in saccade target selection.  They find evidence that D1 receptors modulate the strength of inputs to the frontal eye fields and recurrent connectivity whereas D2 may modulate the output of the FEF. This may be because D1 seems to reduce LTP and LTD, which is consistent with  observations that D1 receptors contribute to associative learning (Puig and Miller, 2012).  Like Puig and Miller (2012), they also found  that D1 blockade increases response perseveration.

    Further reading:
    Puig, M.V. and Miller, E.K. (2012) The role of prefrontal dopamine D1 receptors in the neural mechanisms of associative learning. Neuron. 74: 874-886. View PDF »

  • An animal model of schizophrenia

    Miller Lab
    ,

    Matt Chafee and crew show that monkeys under the influence of ketamine show similar deficits as human schizophrenia patients on a test of context processing.
    Blackman et al 2013

  • The Neuronal Correlate of Consciousness: Unity in Time rather than Space?

    Miller Lab

    Wolf Singer marshals evidence that consciousness is due to information that is widely distributed yet bound together by synchrony into a coherent, distributed metarepresentation.
    Wolf Singer report from The Vatican meeting on Neurosciences and the Human Person

    An example (cited by Singer) of synchrony binding together the neural elements of a thought:
    Buschman, T.J., Denovellis, E.L., Diogo, C., Bullock, D. and Miller, E.K. (2012) Synchronous oscillatory neural ensembles for rules in the prefrontal cortex. Neuron, 76: 838-846.  View PDF

  • Information bottlenecks in posterior parietal cortex: attentional blink?

    Miller Lab

    Attentional blink is decreased attention to a second stimulus if it quickly follows (200-500 ms) another stimulus.  Maloney et al find that neural information  in area LIP tracks attentional blink.

    Maloney et al 2013

  • Straight from The Vatican to you: Brain Rhythms for Cognition and Consciousness

    Miller Lab

    New paper from the Miller Lab:

    Miller, E.K. and Buschman, T.J. “Brain Rhythms for Cognition and Consciousness”. Neurosciences and the Human Person: New Perspectives on Human Activities A. Battro, S. Dehaene and W. Singer (eds), Pontifical Academy of Sciences, Scripta Varia 121, Vatican City, 2013.  View PDF

    Summary: 
    We have discussed how rhythmic synchrony can provide a fundamental backbone for forming and coordinating interactions within and across disparate neural networks. The act of putting neural activity from specific neurons in precise lockstep with specific other neurons may form the ensemble representing a specific thought and regulate which ensembles and larger networks “talk” to one another. The implication is that the signals that underlie cognition do not operate continuously, but rather discretely, withpulses of activity routing packets of information. The advantage is that it constrains and shapes the flow of neural signals. In other words, the brain’s physical infrastructure (i.e., its anatomy) dictates where neural signals can flow; synchronized rhythms dictate where signals do flow. However, this comes at a cost. Any coding scheme based on repeated rhythmic activity is naturally limited in bandwidth; only so many things can be computed or carried in a single oscillatory cycle. This may explain the most fundamental property of conscious thought, its limited capacity.

    Information about our meeting at The Vatican

  • Beta coherence within ventromedial prefrontal cortex precedes affective value choices

    Miller Lab

    More evidence for a role for beta coherence in cognition.
    Lipsman et al     find that an increase in beta coherence in human VM prefrontal cortex just before humans subjectively evaluated faces as “sad” but not before “happy” judgments, especially true when the faces were more ambiguous and thus more difficult to judge.

    Miller Lab work on beta coherence and cognition:

    • Miller, E.K. and Buschman, T.J. (2013) Cortical circuits for the control of attention.  Current Opinion in Neurobiology.  23:216–222  View PDF »
    • Buschman, T.J., Denovellis, E.L., Diogo, C., Bullock, D. and Miller, E.K. (2012) Synchronous oscillatory neural ensembles for rules in the prefrontal cortex. Neuron, 76: 838-846.  View PDF
    • Buschman, T.J. and Miller, E.K. (2009) Serial, covert, shifts of attention during visual search are reflected by the frontal eye fields and correlated with population oscillations. Neuron, 63: 386-396. View PDF »
    • Buschman, T.J. and Miller, E.K. (2007) Top-down versus bottom-up control of attention in the prefrontal and posterior parietal cortices. Science. 315: 1860-1862  View PDF »