Decoding Visual Inputs From Multiple Neurons in the Human Temporal Lobe

2007 ◽  
Vol 98 (4) ◽  
pp. 1997-2007 ◽  
Author(s):  
R. Quian Quiroga ◽  
L. Reddy ◽  
C. Koch ◽  
I. Fried
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Sensory Information ◽  
Single Neurons ◽  
Brain Machine Interfaces ◽  
Extracellular Recordings ◽  
Firing Rates ◽  
Visual Inputs ◽  
Human Temporal Lobe

We investigated the representation of visual inputs by multiple simultaneously recorded single neurons in the human medial temporal lobe, using their firing rates to infer which images were shown to subjects. The selectivity of these neurons was quantified with a novel measure. About four spikes per neuron, triggered between 300 and 600 ms after image onset in a handful of units (7.8 on average), predicted the identity of images far above chance. Decoding performance increased linearly with the number of units considered, peaked between 400 and 500 ms, did not improve when considering correlations among simultaneously recorded units, and generalized to very different images. The feasibility of decoding sensory information from human extracellular recordings has implications for the development of brain–machine interfaces.

scholarly journals Responses of Human Medial Temporal Lobe Neurons Are Modulated by Stimulus Repetition

2010 ◽  
Vol 103 (1) ◽  
pp. 97-107 ◽  
Author(s):  
Carlos Pedreira ◽  
Florian Mormann ◽  
Alexander Kraskov ◽  
Moran Cerf ◽  
Itzhak Fried ◽  
...  
Keyword(s):  
Firing Rate ◽  
Temporal Lobe ◽  
Neural Activity ◽  
Medial Temporal Lobe ◽  
Declarative Memory ◽  
Stimulus Presentation ◽  
Single Neurons ◽  
Stimulus Repetition ◽  
Repeated Stimulus ◽  
Visual Inputs

Recent studies have reported the presence of single neurons with strong responses to visual inputs in the human medial temporal lobe. Here we show how repeated stimulus presentation—photos of celebrities and familiar individuals, landmark buildings, animals, and objects—modulates the firing rate of these cells: a consistent decrease in the neural activity was registered as images were repeatedly shown during experimental sessions. The effect of repeated stimulus presentation was not the same for all medial temporal lobe areas. These findings are consistent with the view that medial temporal lobe neurons link visual percepts to declarative memory.

Burst firing of single neurons in the human medial temporal lobe changes before epileptic seizures

2016 ◽  
Vol 127 (10) ◽  
pp. 3329-3334 ◽  
Author(s):  
Heidemarie Gast ◽  
Johannes Niediek ◽  
Kaspar Schindler ◽  
Jan Boström ◽  
Volker A. Coenen ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Epileptic Seizures ◽  
Burst Firing ◽  
Single Neurons

Category-specific visual responses of single neurons in the human medial temporal lobe

10.1038/78868 ◽  
2000 ◽  
Vol 3 (9) ◽  
pp. 946-953 ◽  
Author(s):  
Gabriel Kreiman ◽  
Christof Koch ◽  
Itzhak Fried
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Single Neurons ◽  
Visual Responses

Characterizing interneuron and pyramidal cells in the human medial temporal lobe in vivo using extracellular recordings

Hippocampus ◽  
2006 ◽  
Vol 17 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Indre V. Viskontas ◽  
Arne D. Ekstrom ◽  
Charles L. Wilson ◽  
Itzhak Fried
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Pyramidal Cells ◽  
Extracellular Recordings

Alternate Task Inhibits Single-neuron Category-selective Responses in the Human Hippocampus while Preserving Selectivity in the Amygdala

2009 ◽  
Vol 21 (2) ◽  
pp. 347-358 ◽  
Author(s):  
Peter N. Steinmetz
Keyword(s):  
Temporal Lobe ◽  
Video Game ◽  
Medial Temporal Lobe ◽  
Hippocampal Neurons ◽  
Single Neuron ◽  
Single Neurons ◽  
Human Epilepsy ◽  
Human Hippocampus ◽  
The Subject

One fifth of neurons in the medial-temporal lobe of human epilepsy patients respond selectively to categories of images, such as faces or cars. Here we show that responses of hippocampal neurons are rapidly modified as subjects alternate (over 60 sec) between two tasks (1) identifying images from a category, or (2) playing a simple video game superimposed on the same images. Category-selective responses, present when a subject identifies categories, are eliminated when the subject shifts to playing the game for 87% of category-selective hippocampal neurons. By contrast, responses in the amygdala are present during both tasks for 72% of category-selective amygdalar neurons. These results suggest that attention to images is required to evoke selective responses from single neurons in the hippocampus, but is not required by neurons in the amygdala.

scholarly journals Reunification of Object and View-Center Background Information in the Primate Medial Temporal Lobe

2021 ◽  
Vol 15 ◽  
Author(s):  
He Chen ◽  
Yuji Naya
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Large Scale ◽  
Scene Perception ◽  
Background Information ◽  
Background Signal ◽  
Related Information ◽  
Visual Inputs ◽  
Electrophysiological Studies ◽  
Ventral Pathway

Recent work has shown that the medial temporal lobe (MTL), including the hippocampus (HPC) and its surrounding limbic cortices, plays a role in scene perception in addition to episodic memory. The two basic factors of scene perception are the object (“what”) and location (“where”). In this review, we first summarize the anatomical knowledge related to visual inputs to the MTL and physiological studies examining object-related information processed along the ventral pathway briefly. Thereafter, we discuss the space-related information, the processing of which was unclear, presumably because of its multiple aspects and a lack of appropriate task paradigm in contrast to object-related information. Based on recent electrophysiological studies using non-human primates and the existing literature, we proposed the “reunification theory,” which explains brain mechanisms which construct object-location signals at each gaze. In this reunification theory, the ventral pathway signals a large-scale background image of the retina at each gaze position. This view-center background signal reflects the first person’s perspective and specifies the allocentric location in the environment by similarity matching between images. The spatially invariant object signal and view-center background signal, both of which are derived from the same retinal image, are integrated again (i.e., reunification) along the ventral pathway-MTL stream, particularly in the perirhinal cortex. The conjunctive signal, which represents a particular object at a particular location, may play a role in scene perception in the HPC as a key constituent element of an entire scene.

scholarly journals Neural models of schizophrenia

2000 ◽  
Vol 2 (3) ◽  
pp. 267-279 ◽  
Keyword(s):  
Information Processing ◽  
Temporal Lobe ◽  
Cognitive Deficits ◽  
Medial Temporal Lobe ◽  
Sensory Information ◽  
Preliminary Evidence ◽  
Neural Models ◽  
Diagnostic Features ◽  
Sensory Information Processing ◽  
Specific Symptoms

Hallucinations and delusions - two diagnostic features of psychosis shared across the spectrum of heterogeneous schizophrenia constructs - can be described in terms of the pathophysiology of sensory information processing: hallucination is the impaired ability to classify representations as internally or externally generated, while delusion is the immutable linking of representations with each other in the absence of external dependency. The key anatomical systems in higher-order information processing are the cortex, thalamus, basal ganglia, and medial temporal lobe, each of which is modulated by neurotransmitter projection systems. Preliminary evidence, concentrating to date on the dorsolateral prefontal cortex, thalamus, and hippocampal region of the medial temporal lobe, points to neural circuitry dysfunction within and between each system in psychosis. This may account for specific symptoms and associated cognitive deficits such as memory impairment, attention deficit, and language disturbance.

scholarly journals Latency and Selectivity of Single Neurons Indicate Hierarchical Processing in the Human Medial Temporal Lobe

2008 ◽  
Vol 28 (36) ◽  
pp. 8865-8872 ◽  
Author(s):  
F. Mormann ◽  
S. Kornblith ◽  
R. Q. Quiroga ◽  
A. Kraskov ◽  
M. Cerf ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Single Neurons ◽  
Hierarchical Processing

scholarly journals Intrinsic neurophysiological properties of hilar ectopic and normotopic dentate granule cells in human temporal lobe epilepsy and a rat model

2015 ◽  
Vol 113 (4) ◽  
pp. 1184-1194 ◽  
Author(s):  
A. L. Althaus ◽  
O. Sagher ◽  
J. M. Parent ◽  
G. G. Murphy
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Granule Cells ◽  
Salient Feature ◽  
Granule Cell Layer ◽  
Disease Stage ◽  
Resting Membrane Potential ◽  
Firing Rates ◽  
Dentate Granule Cells ◽  
Human Temporal Lobe

Hilar ectopic dentate granule cells (DGCs) are a salient feature of aberrant plasticity in human temporal lobe epilepsy (TLE) and most rodent models of the disease. Recent evidence from rodent TLE models suggests that hilar ectopic DGCs contribute to hyperexcitability within the epileptic hippocampal network. Here we investigate the intrinsic excitability of DGCs from humans with TLE and the rat pilocarpine TLE model with the objective of comparing the neurophysiology of hilar ectopic DGCs to their normotopic counterparts in the granule cell layer (GCL). We recorded from 36 GCL and 7 hilar DGCs from human TLE tissue. Compared with GCL DGCs, hilar DGCs in patient tissue exhibited lower action potential (AP) firing rates, more depolarized AP threshold, and differed in single AP waveform, consistent with an overall decrease in excitability. To evaluate the intrinsic neurophysiology of hilar ectopic DGCs, we made recordings from retrovirus-birthdated, adult-born DGCs 2–4 mo after pilocarpine-induced status epilepticus or sham treatment in rats. Hilar DGCs from epileptic rats exhibited higher AP firing rates than normotopic DGCs from epileptic or control animals. They also displayed more depolarized resting membrane potential and wider AP waveforms, indicating an overall increase in excitability. The contrasting findings between disease and disease model may reflect differences between the late-stage disease tissue available from human surgical specimens and the earlier disease stage examined in the rat TLE model. These data represent the first neurophysiological characterization of ectopic DGCs from human hippocampus and prospectively birthdated ectopic DGCs in a rodent TLE model.

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