Preparatory Activity Offenses

The capacity to inhibit a planned action gives human behavior its characteristic flexibility. How this mechanism operates and what factors influence a decision to act or not act remain relatively unexplored. We used EEG readiness potentials (RPs) to examine preparatory activity before each action of an ongoing sequence, in which one action was occasionally omitted. We compared RPs between sequences in which omissions were instructed by a rule (e.g., “omit every fourth action”) and sequences in which the participant themselves freely decided which action to omit. RP amplitude was reduced for actions that immediately preceded a voluntary omission but not a rule-based omission. We also used the regular temporal pattern of the action sequences to explore brain processes linked to omitting an action by time-locking EEG averages to the inferred time when an action would have occurred had it not been omitted. When omissions were instructed by a rule, there was a negative-going trend in the EEG, recalling the rising ramp of an RP. No such component was found for voluntary omissions. The results are consistent with a model in which spontaneously fluctuating activity in motor areas of the brain could bias “free” decisions to act or not.

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Preparatory Activity in Posterior Temporal Cortex Causally Contributes to Object Detection in Scenes

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00845 ◽

2015 ◽

Vol 27 (11) ◽

pp. 2117-2125 ◽

Cited By ~ 11

Author(s):

Reshanne R. Reeder ◽

Francesca Perini ◽

Marius V. Peelen

Keyword(s):

Visual Cortex ◽

Object Detection ◽

Activity Patterns ◽

Temporal Cortex ◽

Relevant Information ◽

Visual Selective Attention ◽

Object Categories ◽

Preparatory Attention ◽

Preparatory Activity ◽

Early Visual Cortex

Theories of visual selective attention propose that top–down preparatory attention signals mediate the selection of task-relevant information in cluttered scenes. Neuroimaging and electrophysiology studies have provided correlative evidence for this hypothesis, finding increased activity in target-selective neural populations in visual cortex in the period between a search cue and target onset. In this study, we used online TMS to test whether preparatory neural activity in visual cortex is causally involved in naturalistic object detection. In two experiments, participants detected the presence of object categories (cars, people) in a diverse set of photographs of real-world scenes. TMS was applied over a region in posterior temporal cortex identified by fMRI as carrying category-specific preparatory activity patterns. Results showed that TMS applied over posterior temporal cortex before scene onset (−200 and −100 msec) impaired the detection of object categories in subsequently presented scenes, relative to vertex and early visual cortex stimulation. This effect was specific to category level detection and was related to the type of attentional template participants adopted, with the strongest effects observed in participants adopting category level templates. These results provide evidence for a causal role of preparatory attention in mediating the detection of objects in cluttered daily-life environments.

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Preparatory activity in motor cortex reflects learning of local visuomotor skills

Nature Neuroscience ◽

10.1038/nn1097 ◽

2003 ◽

Vol 6 (8) ◽

pp. 882-890 ◽

Cited By ~ 114

Author(s):

Rony Paz ◽

Thomas Boraud ◽

Chen Natan ◽

Hagai Bergman ◽

Eilon Vaadia

Keyword(s):

Motor Cortex ◽

Preparatory Activity ◽

Visuomotor Skills

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Aerosols for Concentrating Solar Electricity Production Forecasts: Requirement Quantification and ECMWF/MACC Aerosol Forecast Assessment

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-11-00259.1 ◽

2013 ◽

Vol 94 (6) ◽

pp. 903-914 ◽

Cited By ~ 28

Author(s):

Marion Schroedter-Homscheidt ◽

Armel Oumbe ◽

Angela Benedetti ◽

Jean-Jacques Morcrette

Keyword(s):

Weather Prediction ◽

Global Scale ◽

Atmospheric Composition ◽

Electricity Production ◽

Aerosol Extinction ◽

Grid Integration ◽

Weather Forecasts ◽

Preparatory Activity ◽

To Come ◽

Solar Electricity

The potential for transferring a larger share of our energy supply toward renewable energy is a widely discussed goal in society, economics, environment, and climate-related programs. For a larger share of electricity to come from fluctuating solar and wind energy-based electricity, production forecasts are required to ensure successful grid integration. Concentrating solar power holds the potential to make the fluctuating solar electricity a dispatchable resource by using both heat storage systems and solar production forecasts based on a reliable weather prediction. These solar technologies exploit the direct irradiance at the surface, which is a quantity very dependent on the aerosol extinction with values up to 100%. Results from present-day numerical weather forecasts are inadequate, as they generally use climatologies for dealing with aerosol extinction. Therefore, meteorological forecasts have to be extended by chemical weather forecasts. The paper aims at quantifying on a global scale the question of whether and where daily mean or hourly forecasts are required, or if persistence is sufficient in some regions. It assesses the performance of recently introduced NWP aerosol schemes by using the ECMWF/Monitoring Atmospheric Composition and Climate (MACC) forecast, which is a preparatory activity for the upcoming European Global Monitoring for Environment and Security (GMES) Atmosphere Service.

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Covert Representation of Second-Next Movement in the Pre-Supplementary Motor Area of Monkeys

Journal of Neurophysiology ◽

10.1152/jn.90636.2008 ◽

2009 ◽

Vol 101 (4) ◽

pp. 1883-1889 ◽

Cited By ~ 26

Author(s):

Toshi Nakajima ◽

Ryosuke Hosaka ◽

Hajime Mushiake ◽

Jun Tanji

Keyword(s):

Supplementary Motor Area ◽

Motor Command ◽

Motor Area ◽

Visual Signals ◽

Preparatory Activity ◽

Motor Areas

We attempted to analyze the nature of premovement activity of neurons in medial motor areas [supplementary motor area (SMA) and pre-SMA] from a perspective of coding multiple movements. Monkeys were trained to perform a series of two movements with an intervening delay: supination or pronation with either forearm. Movements were initially instructed with visual signals but had to be remembered thereafter. Although a well-known type of premovement activity representing the forthcoming movements was found in the two areas, we found an unexpected type of activity that represented a second-next movement before initiating the first of the two movements. Typically in the pre-SMA, such activity selective for the second-next movement peaked before the initiation of the first movement, decayed thereafter, and remained low in magnitude while initiating the second movement. This type of activity may tentatively hold information for the second movement while initiating the first. That information may be fed into another group of neurons that themselves build a preparatory activity required to plan the second movements. Alternatively, the activity could serve as a signal to inhibit a premature exertion of the motor command for the second movement.

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Cortical Preparatory Activity: Representation of Movement or First Cog in a Dynamical Machine?

Neuron ◽

10.1016/j.neuron.2010.09.015 ◽

2010 ◽

Vol 68 (3) ◽

pp. 387-400 ◽

Cited By ~ 212

Author(s):

Mark M. Churchland ◽

John P. Cunningham ◽

Matthew T. Kaufman ◽

Stephen I. Ryu ◽

Krishna V. Shenoy

Keyword(s):

Activity Representation ◽

Preparatory Activity

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Neural representations of the target (goal) of visually guided arm movements in three motor areas of the monkey

Journal of Neurophysiology ◽

10.1152/jn.1990.64.1.164 ◽

1990 ◽

Vol 64 (1) ◽

pp. 164-178 ◽

Cited By ~ 243

Author(s):

G. E. Alexander ◽

M. D. Crutcher

Keyword(s):

Primary Motor Cortex ◽

Cell Activity ◽

Motor Area ◽

Visually Guided ◽

Spatial Features ◽

Tracking Tasks ◽

Neural Representations ◽

Preparatory Activity ◽

Standard Task ◽

The Right

1. This study was designed to determine whether the supplementary motor area (SMA), the primary motor cortex (MC), and the putamen, all of which are components of the basal ganglia-thalamocortical “motor circuit,” contain neural representations of the target or goal of a movement, independent of specific features of the movement itself. Four rhesus monkeys were trained to perform two visuomotor delayed step-tracking tasks in which the subject used a cursor to track targets on a display screen by making flexion and extension movements of the elbow. Single-cell activity was recorded from the SMA, MC, and putamen while the monkeys performed the two tasks. In the Standard task, the cursor and the forearm moved in the same direction. The Cursor/Limb Inversion task was identical to the Standard task except that there was an inverse relationship between the directions of movement of the forearm and cursor. Together, these tasks dissociated the spatial features of the target or goal of the movement from those of the movement itself. Both tasks also included features that made it possible to distinguish neuronal activity related to the preparation for movement from that related to movement execution. A total of 554 directionally selective, task-related neurons were tested with both tasks (SMA, 207; MC, 198; putamen, 149). 2. Two types of directionally selective preparatory activity were seen in each motor area. Cells with target-dependent preparatory activity showed selective discharge prior to all preplanned movements of the cursor toward one of the side targets (right or left), irrespective of whether the limb movement involved extension or flexion of the elbow. Comparable proportions of target-dependent preparatory cells were seen in the SMA (36%), MC (40%), and putamen (38%). Cells with limb-dependent preparatory activity showed selective discharge prior to all preplanned elbow movements in a particular direction (extension or flexion), irrespective of whether the target to which the cursor was moved was located on the right or left side of the display. The SMA contained a higher proportion of limb-dependent preparatory cells (40%) than either MC (15%) or putamen (9%). 3. Two types of directionally selective movement-related activity were also seen in each motor area.(ABSTRACT TRUNCATED AT 400 WORDS)

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N2 component of VEP and preparatory activity

International Journal of Psychophysiology ◽

10.1016/0167-8760(91)90048-3 ◽

1991 ◽

Vol 11 (1) ◽

pp. 8

Author(s):

IgorO. Aleksandrov ◽

NataliaE. Maksimova

Keyword(s):

Preparatory Activity

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