Spinal cord compression may induce cortical reorganization. This study follows a patient with cer... more Spinal cord compression may induce cortical reorganization. This study follows a patient with cervical spondylotic myelopathy to investigate changes in cortical activation before and after decompressive surgery. The relationship with functional recovery is also described. A 37-year-old right-hand-dominant man presented a 1-month history of rapidly worsening right-hand clumsiness, right-sided hemiparesis, and gait difficulties. Physical examination confirmed severe right-sided weakness, impaired dexterity, hyperreflexia, and wide-based gait. The patient underwent blood oxygenation level-dependent functional magnetic resonance imaging at 4 T. Images were obtained before and 6 months after an anterior cervical discectomy with insertion of an artificial disk. Blood oxygenation level-dependent functional magnetic resonance imaging was used to detect changes in cortical activation over time during a finger-tapping (motor) paradigm. Improvement in clinical function was recorded with validated clinical tools, including the Japanese Orthopedic Association scale for cervical spondylotic myelopathy, the Nurick neurological function score, and the Neck Disability Index, along with clinical examination. After decompressive cervical spine surgery in a patient with cervical spondylotic myelopathy, functional magnetic resonance imaging detected increased cortical activation in the primary motor cortex during finger tapping. These changes occurred concomitantly with improvement in motor function. Upper- and lower-extremity motor subscores of the Japanese Orthopedic Association scale demonstrated 40% and 43% improvement, respectively. These observations suggest that cortical reorganization or recruitment may accompany the recovery of function after spinal cord injury.
The manipulation of stimulus significance, by instructions from the experimenter, may be taken as... more The manipulation of stimulus significance, by instructions from the experimenter, may be taken as an example of verbal conditioning. Consideration of such a mechanism suggested that personality effects previously found in conditioning studies should be apparent in instructional manipulations of significance in a study of the orienting response (OR) to words. Because of recent changes in dimensioning of the personality structure, some of the items originally used to define Eysenck's extraversion (E) dimension are now used to assess the new dimension of psychoticism (P), suggesting that at least some of the established effects of E upon conditioning may be associated now with P. Hence the P scale was focused on in this study. Words differing on the evaluative dimension of the semantic differential were presented in three blocks, the first under indifferent instructions, the second under instructions to rate the words for their affective impact, and the third under indifferent instructions again. These blocks correspond to baseline, conditioning, and extinction conditions respectively. Electrodermal activity indicated enhanced conditioning, together with greater carry-over effects in the extinction phase, for low-P compared with high-P subjects. The results indicate the importance of personality effects in studies of stimulus significance and illustrate the value of the verbal conditioning mechanism in this area of the OR field. They also suggest the need to re-examine previously obtained E-effects in conditioning studies in light of changing personality tests.
The evoked cardiac response (ECR) of heart rate deceleration, respiratory pause, the peripheral p... more The evoked cardiac response (ECR) of heart rate deceleration, respiratory pause, the peripheral pulse amplitude response (PPAR) of vascular constriction, and the galvanic skin response (GSR) were recorded from 20 subjects presented with a series of brief target and nontarget stimuli in a random order. Prestimulus vigilance was equivalent for the two types of stimuli since each had to be identified as target or nontarget before being processed, or ignored, respectively. This difference in signal value following identification affected only by the GSR, supporting a conceptualization of preliminary processes in orienting response (OR) elicitation rather than Sokolov's unitary OR concept.
We examined putative central nervous system (CNS) indices of tonic and phasic aspects of the orie... more We examined putative central nervous system (CNS) indices of tonic and phasic aspects of the orienting reflex (OR) in a passive event-related potential (ERP) dishabituation paradigm. Pre-stimulus skin conductance level (SCL) and the subsequent skin conductance response (SCR) were used as tonic and phasic OR "yard-sticks", respectively. Their stimulus-response patterns were used to assess two ERP components: the tonic pre-stimulus contingent negative variation (CNV) and the subsequent phasic late positive complex (LPC). SCLs and SCRs derived from each trial of the first train presented were compatible with traditional OR studies. Across-train means were also derived for each of the four measures examined. Arousal changes, as indexed by the SCL, were weak in the CNV which showed an additional expectancy effect. The LPC showed a stimulus-response pattern across trials identical to that of the SCR. This study clarifies links between the traditional autonomic measures of the indifferent OR and its CNS correlates, and encourages an OR perspective and/or interpretation of ERP effects.
The evoked cardiac response (ECR) may be described as the sum of two independent response compone... more The evoked cardiac response (ECR) may be described as the sum of two independent response components: an initial HR deceleration (ECR1) and a slightly later acceleration (ECR2) hypothesized to reflect stimulus registration and cognitive processing load, respectively. This study investigated processing load effects in the ECR and the event-related potential (ERP). Stimulus intensity was varied within subjects, and cognitive load was varied between subjects, in a counting/no counting task with a long interstimulus interval. The ECR showed a significant effect of counting, but not intensity. ERPs showed the expected obligatory processing effects in the N1, and substantial effects of cognitive load in the Late Positive Complex. Both ERP components varied with intensity. These novel data offer support for ANS-CNS similarities in reflecting some aspects of stimulus processing, but further work is needed to understand the possible contribution of ERP subcomponents to these effects.
Spinal cord compression may induce cortical reorganization. This study follows a patient with cer... more Spinal cord compression may induce cortical reorganization. This study follows a patient with cervical spondylotic myelopathy to investigate changes in cortical activation before and after decompressive surgery. The relationship with functional recovery is also described. A 37-year-old right-hand-dominant man presented a 1-month history of rapidly worsening right-hand clumsiness, right-sided hemiparesis, and gait difficulties. Physical examination confirmed severe right-sided weakness, impaired dexterity, hyperreflexia, and wide-based gait. The patient underwent blood oxygenation level-dependent functional magnetic resonance imaging at 4 T. Images were obtained before and 6 months after an anterior cervical discectomy with insertion of an artificial disk. Blood oxygenation level-dependent functional magnetic resonance imaging was used to detect changes in cortical activation over time during a finger-tapping (motor) paradigm. Improvement in clinical function was recorded with validated clinical tools, including the Japanese Orthopedic Association scale for cervical spondylotic myelopathy, the Nurick neurological function score, and the Neck Disability Index, along with clinical examination. After decompressive cervical spine surgery in a patient with cervical spondylotic myelopathy, functional magnetic resonance imaging detected increased cortical activation in the primary motor cortex during finger tapping. These changes occurred concomitantly with improvement in motor function. Upper- and lower-extremity motor subscores of the Japanese Orthopedic Association scale demonstrated 40% and 43% improvement, respectively. These observations suggest that cortical reorganization or recruitment may accompany the recovery of function after spinal cord injury.
The manipulation of stimulus significance, by instructions from the experimenter, may be taken as... more The manipulation of stimulus significance, by instructions from the experimenter, may be taken as an example of verbal conditioning. Consideration of such a mechanism suggested that personality effects previously found in conditioning studies should be apparent in instructional manipulations of significance in a study of the orienting response (OR) to words. Because of recent changes in dimensioning of the personality structure, some of the items originally used to define Eysenck's extraversion (E) dimension are now used to assess the new dimension of psychoticism (P), suggesting that at least some of the established effects of E upon conditioning may be associated now with P. Hence the P scale was focused on in this study. Words differing on the evaluative dimension of the semantic differential were presented in three blocks, the first under indifferent instructions, the second under instructions to rate the words for their affective impact, and the third under indifferent instructions again. These blocks correspond to baseline, conditioning, and extinction conditions respectively. Electrodermal activity indicated enhanced conditioning, together with greater carry-over effects in the extinction phase, for low-P compared with high-P subjects. The results indicate the importance of personality effects in studies of stimulus significance and illustrate the value of the verbal conditioning mechanism in this area of the OR field. They also suggest the need to re-examine previously obtained E-effects in conditioning studies in light of changing personality tests.
The evoked cardiac response (ECR) of heart rate deceleration, respiratory pause, the peripheral p... more The evoked cardiac response (ECR) of heart rate deceleration, respiratory pause, the peripheral pulse amplitude response (PPAR) of vascular constriction, and the galvanic skin response (GSR) were recorded from 20 subjects presented with a series of brief target and nontarget stimuli in a random order. Prestimulus vigilance was equivalent for the two types of stimuli since each had to be identified as target or nontarget before being processed, or ignored, respectively. This difference in signal value following identification affected only by the GSR, supporting a conceptualization of preliminary processes in orienting response (OR) elicitation rather than Sokolov's unitary OR concept.
We examined putative central nervous system (CNS) indices of tonic and phasic aspects of the orie... more We examined putative central nervous system (CNS) indices of tonic and phasic aspects of the orienting reflex (OR) in a passive event-related potential (ERP) dishabituation paradigm. Pre-stimulus skin conductance level (SCL) and the subsequent skin conductance response (SCR) were used as tonic and phasic OR "yard-sticks", respectively. Their stimulus-response patterns were used to assess two ERP components: the tonic pre-stimulus contingent negative variation (CNV) and the subsequent phasic late positive complex (LPC). SCLs and SCRs derived from each trial of the first train presented were compatible with traditional OR studies. Across-train means were also derived for each of the four measures examined. Arousal changes, as indexed by the SCL, were weak in the CNV which showed an additional expectancy effect. The LPC showed a stimulus-response pattern across trials identical to that of the SCR. This study clarifies links between the traditional autonomic measures of the indifferent OR and its CNS correlates, and encourages an OR perspective and/or interpretation of ERP effects.
The evoked cardiac response (ECR) may be described as the sum of two independent response compone... more The evoked cardiac response (ECR) may be described as the sum of two independent response components: an initial HR deceleration (ECR1) and a slightly later acceleration (ECR2) hypothesized to reflect stimulus registration and cognitive processing load, respectively. This study investigated processing load effects in the ECR and the event-related potential (ERP). Stimulus intensity was varied within subjects, and cognitive load was varied between subjects, in a counting/no counting task with a long interstimulus interval. The ECR showed a significant effect of counting, but not intensity. ERPs showed the expected obligatory processing effects in the N1, and substantial effects of cognitive load in the Late Positive Complex. Both ERP components varied with intensity. These novel data offer support for ANS-CNS similarities in reflecting some aspects of stimulus processing, but further work is needed to understand the possible contribution of ERP subcomponents to these effects.
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