Subthreshold Amplitude and Phase Resonance in Single Neurons

AbstractLaser microsurgery has long been an important means of assessing the functions of specific cells and tissues. Most laser ablation systems use short, highly focused laser pulses to create plasma-mediated lesions with dimensions on the order of the wavelength of light. While the small size of the lesion enables ablation with high spatial resolution, it also makes it difficult to ablate larger structures. We developed an infrared laser ablation system capable of thermally lesioning tissues with spot sizes tunable by the duration and amplitude of laser pulses. We used our laser system in the roundworm C. elegans to kill single neurons and to sever the dorsal and ventral nerve cords, structures that are difficult to lesion using a plasma-based ablation system. We used these ablations to investigate the source of convulsions in a gain-of-function mutant for the acetylcholine receptor ACR-2. Severing the ventral nerve cord caused convulsions to occur independently anterior and posterior to the lesion, suggesting that convulsions can arise independently from distinct subsets of the motor circuit.

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Excitatory Convergence of Y and Non-Y Information Channels on Single Neurons in the PMLS Area, a Motion Area of the Cat Visual Cortex

European Journal of Neuroscience ◽

10.1111/j.1460-9568.1997.tb01443.x ◽

1997 ◽

Vol 9 (5) ◽

pp. 921-933 ◽

Cited By ~ 8

Author(s):

C. Wang ◽

B. Dreher ◽

K. R. Huxlin ◽

W. Burke

Keyword(s):

Visual Cortex ◽

Single Neurons ◽

Cat Visual Cortex ◽

Information Channels

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Activity of single neurons in the monkey amygdala during performance of a visual discrimination task

Journal of Neurophysiology ◽

10.1152/jn.1992.67.6.1447 ◽

1992 ◽

Vol 67 (6) ◽

pp. 1447-1463 ◽

Cited By ~ 87

Author(s):

K. Nakamura ◽

A. Mikami ◽

K. Kubota

Keyword(s):

Visual Stimulus ◽

Visual Discrimination ◽

Discrimination Task ◽

Discharge Rate ◽

Visual Stimuli ◽

Delay Period ◽

Visual Discrimination Task ◽

Single Neurons ◽

Visual Neurons ◽

Human Faces

1. The activity of single neurons was recorded extracellularly from the monkey amygdala while monkeys performed a visual discrimination task. The monkeys were trained to remember a visual stimulus during a delay period (0.5-3.0 s), to discriminate a new visual stimulus from the stimulus, and to release a lever when the new stimulus was presented. Colored photographs (human faces, monkeys, foods, and nonfood objects) or computer-generated two-dimensional shapes (a yellow triangle, a red circle, etc.) were used as visual stimuli. 2. The activity of 160 task-related neurons was studied. Of these, 144 (90%) responded to visual stimuli, 13 (8%) showed firing during the delay period, and 9 (6%) responded to the reward. 3. Task-related neurons were categorized according to the way in which various stimuli activated the neurons. First, to evaluate the proportion of all tested stimuli that elicited changes in activity of a neuron, selectivity index 1 (SI1) was employed. Second, to evaluate the ability of a neuron to discriminate a stimulus from another stimulus, SI2 was employed. On the basis of the calculated values of SI1 and SI2, neurons were classified as selective and nonselective. Most visual neurons were categorized as selective (131/144), and a few were characterized as nonselective (13/144). Neurons active during the delay period were also categorized as selective visual and delay neurons (6/13) and as nonselective delay neurons (7/13). 4. Responses of selective visual neurons had various temporal and stimulus-selective properties. Latencies ranged widely from 60 to 300 ms. Response durations also ranged widely from 20 to 870 ms. When the natures of the various effective stimuli were studied for each neuron, one-fourth of the responses of these neurons were considered to reflect some categorical aspect of the stimuli, such as human, monkey, food, or nonfood object. Furthermore, the responses of some neurons apparently reflected a certain behavioral significance of the stimuli that was separate from the task, such as the face of a particular person, smiling human faces, etc. 5. Nonselective visual neurons responded to a visual stimulus, regardless of its nature. They also responded in the absence of a visual stimulus when the monkey anticipated the appearance of the next stimulus. 6. Selective visual and delay neurons fired in response to particular stimuli and throughout the subsequent delay periods. Nonselective delay neurons increased their discharge rates gradually during the delay period, and the discharge rate decreased after the next stimulus was presented. 7. Task-related neurons were identified in six histologically distinct nuclei of the amygdala.(ABSTRACT TRUNCATED AT 400 WORDS)

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Neuronal adaptation: Delay compensation at the level of single neurons?

Behavioral and Brain Sciences ◽

10.1017/s0140525x08003944 ◽

2008 ◽

Vol 31 (2) ◽

pp. 210-212 ◽

Cited By ~ 1

Author(s):

J. Patrick Mayo ◽

Marc A. Sommer

Keyword(s):

Visual Processing ◽

Visual Input ◽

Single Neurons ◽

Delay Compensation ◽

Time Intervals ◽

Neuronal Adaptation ◽

First Response ◽

Late Stages

AbstractSaccades divide visual input into rapid, discontinuous periods of stimulation on the retina. The response of single neurons to such sequential stimuli is neuronal adaptation; a robust first response followed by an interval-dependent diminished second response. Adaptation is pervasive in both early and late stages of visual processing. Given its inherent coding of brief time intervals, neuronal adaptation may play a fundamental role in compensating for visual delays.

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Some Quantitative Methods for the Study of Spontaneous Activity of Single Neurons

Biophysical Journal ◽

10.1016/s0006-3495(62)86860-x ◽

1962 ◽

Vol 2 (4) ◽

pp. 351-368 ◽

Cited By ~ 210

Author(s):

R.W. Rodieck ◽

N.Y.-S. Kiang ◽

G.L. Gerstein

Keyword(s):

Spontaneous Activity ◽

Quantitative Methods ◽

Single Neurons

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