Prefrontal cortical plasticity during learning of cognitive tasks

AbstractTraining in working memory tasks is associated with lasting changes in prefrontal cortical activity. To assess the neural activity changes induced by training, we recorded single units, multi-unit activity (MUA) and local field potentials (LFP) with chronic electrode arrays implanted in the prefrontal cortex of two monkeys, throughout the period they were trained to perform cognitive tasks. Mastering different task phases was associated with distinct changes in neural activity, which included recruitment of larger numbers of neurons, increases or decreases of their firing rate, changes in the correlation structure between neurons, and redistribution of power across LFP frequency bands. In every training phase, changes induced by the actively learned task were also observed in a control task, which remained the same across the training period. Our results reveal how learning to perform cognitive tasks induces plasticity of prefrontal cortical activity, and how activity changes may generalize between tasks.

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Training-induced prefrontal neuronal changes transfer between tasks

10.1101/2020.10.22.351197 ◽

2020 ◽

Author(s):

Hua Tang ◽

Mitchell R. Riley ◽

Balbir Singh ◽

Xue-Lian Qi ◽

David T. Blake ◽

...

Keyword(s):

Neural Activity ◽

Training Transfer ◽

Phase Changes ◽

Single Units ◽

Cognitive Tasks ◽

Field Potentials ◽

Electrode Arrays ◽

Control Task ◽

Neural Basis ◽

Neural Substrate

AbstractTraining to improve working memory is associated with changes in prefrontal activation and confers lasting benefits, some of which generalize to untrained tasks, though the issue remains contentious and the neural substrate underlying such transfer are unknown. To assess how neural activity changes induced by training transfer across tasks, we recorded single units, multi-unit activity (MUA) and local field potentials (LFP) with chronic electrode arrays implanted in the prefrontal cortex of two monkeys, as they were trained to perform cognitive tasks. Mastering different tasks was associated with distinct changes in neural activity, which included redistribution of power across frequency bands in the LFP, recruitment of larger numbers of MUA sites, and increase or decrease of mean neural activity across single units. In every training phase, changes induced by the actively learned task transferred to an untrained control task, which remained the same across the training period. The results explicate the neural basis through which training can transfer across cognitive tasks.

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Horizontal spread of synchronized activity in neocortex and its control by GABA-mediated inhibition

Journal of Neurophysiology ◽

10.1152/jn.1989.61.4.747 ◽

1989 ◽

Vol 61 (4) ◽

pp. 747-758 ◽

Cited By ~ 324

Author(s):

Y. Chagnac-Amitai ◽

B. W. Connors

Keyword(s):

Neural Activity ◽

Single Cells ◽

Epileptiform Activity ◽

Cortical Activity ◽

Synaptic Activity ◽

Cortical Inhibition ◽

Field Potentials ◽

Bathing Medium ◽

Horizontal Spread ◽

Epileptiform Events

1. Suppression of GABAA receptor-mediated inhibition disrupts the neural activity of neocortex and can lead to synchronized discharges that mimic those of partial epilepsy. We have studied the role of GABAA-mediated inhibition in controlling the synchronization and horizontal (tangential) spread of cortical activity. 2. Slices of rat SmI were maintained in vitro and focally stimulated in layer VI while recording with a horizontal array of extracellular electrodes. Inhibition was slightly suppressed by adding low concentrations of the GABAA antagonists bicuculline or bicuculline methiodide to the bathing medium. Under control conditions neural activity was narrowly confined to a vertical strip of cortex. The horizontal spread of activity expanded about twofold in the presence of antagonist concentrations (less than or equal to 0.5 microM) that were expected to suppress GABAA function by no more than 10-20%. 3. At antagonist concentrations between 0.4 and 1.0 microM, evoked epileptiform activity appeared. These threshold-dose epileptiform events showed wide variations in size and duration (even at the same recording site), very variable distances of horizontal propagation, specific sites of propagation failure, reversals of propagation direction, and directional asymmetries in their probability of propagation. This contrasts with activity observed previously (Ref. 9) in high bicuculline concentrations (greater than or equal to 10 microM): large, stereotyped events that propagate reliably without decrement or reflection. 4. Intracellular recordings were obtained from pyramidal neurons in layers II/III in the presence of less than or equal to 1 microM bicuculline. Inhibitory postsynaptic potentials (IPSPs) were observed during both primary evoked responses and propagating epileptiform events and were often comparable in size and duration to those in untreated cortex. Epileptiform field potentials were always correlated with synaptic activity in single cells, but the pattern and type of PSPs varied with the form of the field potentials. Large amplitude epileptiform events coincided with an overwhelming inhibition of upper layer neurons. 5. We conclude that 1) the horizontal spread of normal cortical activity is strongly constrained by GABAA-mediated IPSPs, 2) a relatively small reduction in the efficacy of inhibition leads to a large increase in the spread of excitation, 3) initiation and propagation of synchronized epileptiform activity can occur even in the presence of robust cortical inhibition, and 4) the character of epileptiform activity is strongly affected by the influences of inhibition.

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Phosphodiesterase type 1 inhibition alters medial prefrontal cortical activity during goal-driven behaviour and partially reverses neurophysiological deficits in the rat phencyclidine model of schizophrenia

Neuropharmacology ◽

10.1016/j.neuropharm.2021.108454 ◽

2021 ◽

Vol 186 ◽

pp. 108454

Author(s):

Jessica Hayes ◽

Bettina Laursen ◽

Elin Eneberg ◽

Jan Kehler ◽

Lars Kyhn Rasmussen ◽

...

Keyword(s):

Cortical Activity ◽

Prefrontal Cortical ◽

Phosphodiesterase Type ◽

Medial Prefrontal Cortical

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Eyeblink conditioning contingent on hippocampal theta enhances hippocampal and medial prefrontal responses

Journal of Neurophysiology ◽

10.1152/jn.00801.2010 ◽

2011 ◽

Vol 105 (5) ◽

pp. 2213-2224 ◽

Cited By ~ 19

Author(s):

Ryan D. Darling ◽

Kanako Takatsuki ◽

Amy L. Griffin ◽

Stephen D. Berry

Keyword(s):

Neural Activity ◽

Theta Rhythm ◽

Eyeblink Conditioning ◽

Trace Conditioning ◽

Distributed Network ◽

Field Potentials ◽

Trace Interval ◽

Behavioral Learning ◽

Paired Group ◽

Hippocampal Theta

Trace eyeblink classical conditioning (tEBCC) can be accelerated by making training trials contingent on the naturally generated hippocampal 3- to 7-Hz theta rhythm. However, it is not well-understood how the presence (or absence) of theta affects stimulus-driven changes within the hippocampus and how it correlates with patterns of neural activity in other essential trace conditioning structures, such as the medial prefrontal cortex (mPFC). In the present study, a brain-computer interface delivered paired or unpaired conditioning trials to rabbits during the explicit presence (T+) or absence (T−) of theta, yielding significantly faster behavioral learning in the T+-paired group. The stimulus-elicited hippocampal unit responses were larger and more rhythmic in the T+-paired group. This facilitation of unit responses was complemented by differences in the hippocampal local field potentials (LFP), with the T+-paired group demonstrating more coherent stimulus-evoked theta than T−-paired animals and both unpaired groups. mPFC unit responses in the rapid learning T+-paired group displayed a clear inhibitory/excitatory sequential pattern of response to the tone that was not seen in any other group. Furthermore, sustained mPFC unit excitation continued through the trace interval in T+animals but not in T−animals. Thus theta-contingent training is accompanied by 1) acceleration in behavioral learning, 2) enhancement of the hippocampal unit and LFP responses, and 3) enhancement of mPFC unit responses. Together, these data provide evidence that pretrial hippocampal state is related to enhanced neural activity in critical structures of the distributed network supporting the acquisition of tEBCC.

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The Neural Sociometer: Brain Mechanisms Underlying State Self-esteem

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00027 ◽

2011 ◽

Vol 23 (11) ◽

pp. 3448-3455 ◽

Cited By ~ 100

Author(s):

Naomi I. Eisenberger ◽

Tristen K. Inagaki ◽

Keely A. Muscatell ◽

Kate E. Byrne Haltom ◽

Mark R. Leary

Keyword(s):

Negative Feedback ◽

Cortical Activity ◽

Self Esteem ◽

Anterior Insula ◽

Lower State ◽

Social Connection ◽

Prefrontal Cortical ◽

Referential Processing ◽

Neural Underpinnings ◽

Medial Prefrontal Cortical

On the basis of the importance of social connection for survival, humans may have evolved a “sociometer”—a mechanism that translates perceptions of rejection or acceptance into state self-esteem. Here, we explored the neural underpinnings of the sociometer by examining whether neural regions responsive to rejection or acceptance were associated with state self-esteem. Participants underwent fMRI while viewing feedback words (“interesting,” “boring“) ostensibly chosen by another individual (confederate) to describe the participant's previously recorded interview. Participants rated their state self-esteem in response to each feedback word. Results demonstrated that greater activity in rejection-related neural regions (dorsal ACC, anterior insula) and mentalizing regions was associated with lower-state self-esteem. Additionally, participants whose self-esteem decreased from prescan to postscan versus those whose self-esteem did not showed greater medial prefrontal cortical activity, previously associated with self-referential processing, in response to negative feedback. Together, the results inform our understanding of the origin and nature of our feelings about ourselves.

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Characterizing prefrontal cortical activity during inhibition task in methamphetamine-associated psychosis versus schizophrenia: a multi-channel near-infrared spectroscopy study

Addiction Biology ◽

10.1111/adb.12224 ◽

2015 ◽

Vol 21 (2) ◽

pp. 489-503 ◽

Cited By ~ 15

Author(s):

Naohiro Okada ◽

Katsuyoshi Takahashi ◽

Yukika Nishimura ◽

Shinsuke Koike ◽

Ayaka Ishii-Takahashi ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Cortical Activity ◽

Spectroscopy Study ◽

Prefrontal Cortical

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Cross-modal orienting of exogenous attention results in visual-cortical facilitation, not suppression

10.1101/2020.10.13.338210 ◽

2020 ◽

Author(s):

Jonathan M. Keefe ◽

Emilia Pokta ◽

Viola S. Störmer

Keyword(s):

Neural Activity ◽

Target Location ◽

Visual Target ◽

Cortical Activity ◽

Exogenous Attention ◽

Peripheral Target ◽

Behavioral Performance ◽

Auditory Cue ◽

Visual Cortical

AbstractAttention may be oriented exogenously (i.e., involuntarily) to the location of salient stimuli, resulting in improved perception. However, it is unknown whether exogenous attention improves perception by facilitating processing of attended information, suppressing processing of unattended information, or both. To test this question, we measured behavioral performance and cue-elicited neural changes in the electroencephalogram as participants (N = 19) performed a task in which a spatially non-predictive auditory cue preceded a visual target. Critically, this cue was either presented at a peripheral target location or from the center of the screen, allowing us to isolate spatially specific attentional activity. We find that both behavior and attention-mediated changes in visual-cortical activity are enhanced at the location of a cue prior to the onset of a target, but that behavior and neural activity at an unattended target location are equivalent to that following a central cue that does not direct attention (i.e., baseline). These results suggest that exogenous attention operates solely via facilitation of information at an attended location.

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Multi-shanks SiNAPS Active Pixel Sensor CMOS probe: 1024 simultaneously recording channels for high-density intracortical brain mapping

10.1101/749911 ◽

2019 ◽

Author(s):

Fabio Boi ◽

Nikolas Perentos ◽

Aziliz Lecomte ◽

Gerrit Schwesig ◽

Stefano Zordan ◽

...

Keyword(s):

Neural Activity ◽

Brain Activity ◽

Brain Area ◽

Large Population ◽

Brain Structures ◽

High Density ◽

Single Neurons ◽

Electrode Arrays ◽

Unit Recording ◽

Recording Channels

AbstractThe advent of implantable active dense CMOS neural probes opened a new era for electrophysiology in neuroscience. These single shank electrode arrays, and the emerging tailored analysis tools, provide for the first time to neuroscientists the neurotechnology means to spatiotemporally resolve the activity of hundreds of different single-neurons in multiple vertically aligned brain structures. However, while these unprecedented experimental capabilities to study columnar brain properties are a big leap forward in neuroscience, there is the need to spatially distribute electrodes also horizontally. Closely spacing and consistently placing in well-defined geometrical arrangement multiple isolated single-shank probes is methodologically and economically impractical. Here, we present the first high-density CMOS neural probe with multiple shanks integrating thousand’s of closely spaced and simultaneously recording microelectrodes to map neural activity across 2D lattice. Taking advantage from the high-modularity of our electrode-pixels-based SiNAPS technology, we realized a four shanks active dense probe with 256 electrode-pixels/shank and a pitch of 28 µm, for a total of 1024 simultaneously recording channels. The achieved performances allow for full-band, whole-array read-outs at 25 kHz/channel, show a measured input referred noise in the action potential band (300-7000 Hz) of 6.5 ± 2.1µVRMS, and a power consumption <6 µW/electrode-pixel. Preliminary recordings in awake behaving mice demonstrated the capability of multi-shanks SiNAPS probes to simultaneously record neural activity (both LFPs and spikes) from a brain area >6 mm2, spanning cortical, hippocampal and thalamic regions. High-density 2D array enables combining large population unit recording across distributed networks with precise intra- and interlaminar/nuclear mapping of the oscillatory dynamics. These results pave the way to a new generation of high-density and extremely compact multi-shanks CMOS-probes with tunable layouts for electrophysiological mapping of brain activity at the single-neurons resolution.

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The Psychotomimetic Nature of Dreams: An Experimental Study

Schizophrenia Research and Treatment ◽

10.1155/2012/872307 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4 ◽

Cited By ~ 5

Author(s):

Oliver Mason ◽

Dominic Wakerley

Keyword(s):

Experimental Study ◽

Rem Sleep ◽

Cortical Activity ◽

Prefrontal Cortical ◽

Drug Studies ◽

Cognition And Affect

Several theories promote the similarities between dreaming and psychosis, but this has rarely been tested empirically. We assessed dreaming and waking reality using the Psychotomimetic States Inventory, a measure of psychotic-like experience originally designed for drug studies. Twenty participants completed the measure in each of two dream conditions and one waking condition. Dreams were assessed upon waking naturally and also using a movement-activated (actigraph) alarm during the night. Overall, participants reported more quasipsychotic characteristics during dreams (in both conditions) than when awake. This was most marked for paranoia and delusional thinking, but differences were also seen for perceptual abnormalities, mania, and anhedonia. The quality of dream experience seems particularly similar to psychosis in sometimes being highly self-referential and having a paranoid content. Subjective changes to cognition and affect are consistent with alterations in prefrontal cortical activity during REM sleep that mirror those of schizophrenia.

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