Simultaneous spike-time locking to multiple frequencies

Locking of neuronal spikes to external and internal signals is a ubiquitous neurophysiological mechanism that has been extensively studied in several brain areas and species. Using experimental data from the electrosensory system and concise mathematical models, we analyze how a single neuron can simultaneously lock to multiple frequencies. Our findings demonstrate how temporal and rate codes can complement each other and lead to rich neuronal representations of sensory signals.

Alpha oscillations govern interhemispheric spike timing coordination in the honey bee brain

In 1929 Hans Berger discovered the alpha oscillations: prominent, ongoing oscillations around 10 Hz in the electroencephalogram of the human brain. These alpha oscillations are among the most widely studied brain signals, related to cognitive phenomena such as attention, memory and consciousness. However, the mechanisms by which alpha oscillations affect human cognition await demonstration. Here, we suggest the honey bee brain as an experimentally more accessible model system for investigating the functional role of alpha oscillations. We found a prominent spontaneous oscillation around 18 Hz that is reduced in amplitude upon olfactory stimulation. Similar to alpha oscillations in primates, the phase of this oscillation biased both timing of neuronal spikes and amplitude of high-frequency gamma activity (40–450 Hz). These results suggest a common role of alpha oscillations across phyla and provide an unprecedented new venue for causal studies on the relationship between neuronal spikes, brain oscillations and cognition.

Alpha oscillations govern interhemispheric spike timing coordination in the honey bee brain

In 1929 Hans Berger discovered the alpha oscillations: a prominent, ongoing 10 Hz rhythm in the human electroencephalogram (EEG). These alpha oscillations are amongst the most widely studied cerebral signals, related to cognitive phenomena such as attention, memory, and consciousness. However, the mechanisms by which alpha oscillations affect human cognition await demonstration. Here we suggest the honey bee brain as an experimentally more accessible model system for investigating the functional roles of alpha oscillations. We found a prominent alpha wave-like spontaneous neural activity (~ 18 Hz) that is reduced in amplitude upon stimulus presentation. The phase of this alpha activity biased both timing of neuronal spikes and amplitude of high-frequency gamma activity (~ 30 Hz). These results suggest a common role of oscillatory neuronal activity across phyla and provide an unprecedented new venue for causal studies on the relationship between neuronal spikes, brain oscillations, and cognition.

Visual area V4 encodes history dependent attentional effort and single-trial perceptual detection

ABSTRACTIntense attentional effort improves performance. Neurons in visual area V4 exhibit changes in spike rates that are correlated with effort, selective attention and absolute reward expectation. How neuronal spikes in V4 encode attentional states and perceptual performance with reference to other task relevant motivational and decision signals is poorly understood. We recorded neuronal spikes from monkey visual area V4, and isolated attentional effort from reward expectancy and motor decisions in a visual orientation detection task using a statistical approach based on generalized linear models. We found that V4 spike responses exhibit hysteresis with reward changes. Single trial spiking activity encodes a combination of temporally overlapping sensory and cognitive signals. Neuronal spikes integrate contextual history of attentional effort on a longer time scale, and task related perceptual detection in a shorter timescale within a single trial. Notably, immediate reward expectation and behavioral choice probability are poor predictors of V4 spikes throughout the trial. Further, detection of task relevant perceptual signal is decoded from single trial population spikes with high accuracy. These results provide a detailed representation of perceptual and cognitive signals in V4 that are crucial for performance.