Related Experiment Video
Updated: Jan 31, 2026
Murine Model of Controlled Cortical Impact for the Induction of Traumatic Brain Injury
Published on: August 16, 2019
Simultaneous measurement of perceptual and motor cortical potentials: implications for assessing information
Henry L Lew1, Max Gray, John H Poole
1Harvard Medical School, Boston, Massachusetts, USA.
Objective:
Psychomotor slowing is a common manifestation of traumatic brain injury. Previous electrophysiological studies of traumatic brain injury have focused on abnormal attentional and perceptual responses to incoming stimuli. We hypothesize that traumatic brain injury is also associated with abnormal cortical components of motor execution.
Design:
To test this hypothesis, we analyzed event-related potentials of 22 subjects (11 with a history of severe traumatic brain injury and 11 age-matched healthy subjects) during oddball discrimination tasks. In addition to the usual stimulus-locked averaging of electrophysiological data to reveal cognitive components, such as the P300, we also analyzed subjects' response-locked data to reveal motor potential waveforms. To focus on generalized effects across modality, analyses were performed on composite measures from both auditory and visual event-related potentials.
Results:
(1) Traumatic brain injury subjects had abnormal P300 responses (with reduced amplitude and prolonged latency) in both sensory modalities. (2) Traumatic brain injury subjects' motor potential waveforms showed significantly reduced amplitude in both sensory modalities. (3) Abnormalities in P300 latency, amplitude, and motor potential amplitude (effect sizes = 1.2-1.5 SD) were greater than behavioral slowing, as measured by reaction times (0.7 SD). (4) P300 latency and motor potential amplitude together accounted for much of the reaction time prolongation (r = 0.73).
Conclusions:
This study demonstrates the value of concurrently analyzing stimulus-locked and response-locked event-related potential data to evaluate cortical components of perceptual and motor processing. The present findings indicate that patients with traumatic brain injury have impairments in both the perceptual interpretation of incoming stimuli and the execution of motor responses and that both abnormalities contribute to psychomotor slowing in patients with traumatic brain injury.
Related Concept Videos
01:12Perceptual Constancy
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
03:02Standard Electrode Potentials
01:25Role of Communication in the Nursing Process I: Assessment and Diagnosis
The nursing process considers the patient's emotional and physical well-being. The process can be repeated or stopped at any point if judged essential. Assessment is the first step in the nursing...
01:20Traumatic Memory
00:52Potential Energy
Chemical bonds that form attractive forces between atoms also contain potential energy, called chemical energy. When a chemical reaction...
02:58Cell Potential and Free Energy
Thermodynamics is the branch of physics dealing with the relationship between heat and other forms of energy. In an electrochemical cell, chemical energy is converted into electrical energy.
Thus, a link can be predicted between cell potential, free energy change, and the equilibrium constant for the reaction. Cell potential can also be measured as the oxidant or the reducing strength, and similar acid-base strength measures are reflected in equilibrium...