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PubMed1995

Response selection deficits in frontal excisions.

We compared the performance of patients with frontal excisions, patients with temporal excisions and controls in tasks involving speeded choice responses in which a number of variables were manipulated including: perceptual difficulty, stimulus and response set-size, associative complexity, and spatial stimulus-response compatibility. Response times were sensitive to all manipulations but did not show any group differences. The error rates of the three groups were equally affected by perceptual difficulty and response set-size but frontals were preferentially affected by spatial S-R compatibility, associative complexity, and the number of stimuli per response. The results are consistent with a basic deficit in response selection processes which could underly many problems produced by frontal lesions.

Adult↗
PubMed1966

Selective response of the Japanese quail to various strains of Rous sarcoma virus.

Shipman, Charles Jr. (Indiana University School of Medicine, Indianapolis), and Alvin S. Levine. Selective response of the Japanese quail to various strains of Rous sarcoma virus. J. Bacteriol. 92:161-163. 1966.-The Bryan "high-titer," Carr-Zilber, Harris, Prague, Schmidt-Ruppin, and "29" strains of Rous sarcoma virus were used to initiate tumors in the Japanese quail (Coturnix coturnix japonica). Although all strains produced tumors upon primary inoculation, only the Bryan "high-titer" and Harris strains could be serially passaged with cell-free tumor extracts. Analysis by means of the end-point dilution technique and the interference test revealed that the tumor extract of the Bryan "high-titer" strain passaged 10 times in the quail contained a Rous-associated virus.

Animals↗
PubMed2006

Attentional set mixing: Effects on target selection and selective response activation.

Performance is impaired under set mixing conditions that require frequent readjustments of attentional focus over an extended time period. We compared set repetitions within pure blocks (constant focus of attention) to physically identical repetitions within mixed blocks (changing focus of attention). The aim was to investigate how set mixing affects target selection, indexed by the N2pc component, and selective response activation, indexed by the lateralized readiness potential (LRP). We found that set mixing prolonged the evolution of the N2pc while leaving its onset unaffected. Impaired target selection indicated by the N2pc mixing effect also delayed the start of response planning indexed by an onset delay of the stimulus-locked LRP, explaining one part of the behavioral mixing cost. A larger part of mixing cost could be attributed to a prolonged response planning phase, indexed by an earlier onset of the response-locked LRP.

Adult↗
PubMed1978

The effect of malathion on the temperature selection response of the common shiner, Notropis cornutus (Mitchill).

Warm- (17 degrees C) and cold-acclimated (8 degrees C) young-of-the-year, 1-year-old, and 2-year-old common shiners, Notropis cornutus (Mitchell) were exposed for 24 hr to sublethal doses (1.0, 0.25, and 0.05 microgram/L) of malathion to determine the effect of environmental concentrations of this compound on temperature selection. All three factors studied (acclimation temperature, age, and concentration) were found to affect the temperature selection response of malathion-treated fish. Malathion produced dose-dependent decreases in selected temperature (1.9 degrees to 4.3 degrees C below controls) in 17 degrees C-acclimated fish but not in 8 degrees C-acclimated fish. Two-year-olds treated with 1.0 microgram/L displayed the greatest lowering of selected temperature, followed by two-year-olds treated with 0.25 micrgram/L. One-year-olds treated with 1.0 microgram/L showed a slight lowering, while no downward shifts in selected temperature were found for young-of-the-year. Exposure to 0.05 microgram/L had no effect on any age group. Two-year-olds acclimated to 17 degrees C and exposed to 1.0 microgram/L malathion for 24 hr were placed in clean water and allowed to recover from the pesticide. It was found that the lowered selected temperature induced by malathion returned to that of the controls in 24 hr.

Aging↗
PubMed2003

Selective response of dermal Th-1 cells to 20-50 kDa streptococcal cell-wall proteins in chronic plaque psoriasis.

We have recently described a dermal Th-1 subset in skin lesions of psoriasis which recognizes cell-wall extract isolated from group A streptococci (GAS). As a first step in the identification of the streptococcal proteins involved, dermal T-cell lines (TCL) cultured from the lesional skin of 12 human leucocyte antigen (HLA)-typed psoriasis patients were stimulated with GAS cell-wall extract and 14 fractions (MWt approximately 20-100 kDa) separated from the cell-wall extract by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and electroelution, stained for intracellular interferon-gamma(IFN-gamma) expression and analysed by flow cytometry. All the TCL responded to GAS cell-wall extract to varying extents (3.5-27.6% IFN-gamma+). This response was consistently directed against 20-50 kDa cell-wall fractions and inhibited by anti-HLA-DR antibody. TCL with higher responses to GAS cell-wall extract recognized a larger number of fractions within this range than the lower responder TCL. No difference between the level and pattern of response to the fractions was observed for TCL from HLA-DR7+ (n = 6) and HLA-DR7- (n = 6) individuals. This preliminary study has shown a selective response to lower MWt proteins expressed on GAS cell wall by skin Th-1 cells in psoriasis. Further studies are required to identify the proteins involved.

Adult↗
PubMedDate not supplied

Selected response test items.

Classroom assessment is complex and challenging. Teachers need to consider the cognitive, affective, and psychomotor levels for achievement of their educational objectives. This series of six articles discusses how to develop testing blue-prints; selected-response tests, including multiple-choice, true-false, matching, or other objective tests; completion or essay testing; problem solving/critical thinking activities; performance assessment; and computer-based testing.

Education, Nursing, Baccalaureate↗
PubMed2002

Probing the response selection bottleneck with a cardiac measure: individual differences in strategy for a psychological refractory period task.

We examined the coordination of processing streams when two reaction stimuli are presented with minimal temporal separation (the psychological refractory period, PRP, paradigm). We tested the hypothesis that individuals that grouped responses to the two stimuli would schedule response preparation later than those not-grouping their responses would. Performance measures were combined with a cardiac measure interpreted as an index of response inhibition. Forty-two college-aged participants performed an auditory choice task followed in 50, 100 or 400 ms by a visual choice reaction time (RT) task. Performance results replicated prior work. The timing of cardiac inter-beat intervals (IBIs) showed that participants grouping their reactions did appear to delay response preparation; while Non-Groupers promptly initiated response selection for the initial task. These results generally supported the importance of preparation for understanding the coordination of processing streams.

Adult↗
PubMed2005

Selective response to letter categorization within the left fusiform gyrus.

Neuroimaging studies that look at reading processes using words, pseudowords, nonwords and letters frequently report specific left fusiform gyrus (BA37) activations. In the present study, we examined fMRI signal variations within the left and right BA37 for paired Latin letters, Korean letters and geometrical figures in discrimination and categorization tasks. Data of Pernet et al. (Pernet, C., Franceries, X., Basan, S., Cassol, E., Démonet, J.F., Celsis, P., 2004. Anatomy and time course of discrimination and categorization processes in vision: an fMRI study. NeuroImage 22, 1563-1577) were re-analyzed using a ROI methodology that highlights the selective response of the left BA37 to Latin letter categorization. First, differences according to stimulus type were observed for the categorization task only. Second, we found weaker activation for Latin letter categorization than for both geometrical figure and Korean letter categorization. Third, only Latin letter categorization elicited as left-sided activation, although the direct comparison between regions did not demonstrate a significant difference. These data suggest that the left fusiform gyrus sustains access to letter representations in memory; and results are discussed with reference to the relationship between letter categorization and word recognition and to selective vs. specific (i.e. task-independent) neural response.

Adult↗
PubMed1990

Organization of sensory discrimination and response selection in choice and nonchoice conditions: a study using cerebral evoked potentials in normal humans.

1. It has been suggested that the long-latency "event-related" cerebral evoked potentials (ERPs) reflect certain aspects of the neural processing underlying sensory discrimination in a two-choice reaction time task. The present paper examines the hypothesis that the coupling of these ERPs to sensory discrimination is variable and that the discrimination process is completed at different points during the course of cerebral processing, depending on the actual requirements of the task. 2. We recorded the cerebral evoked potentials and electromyogram (EMG) of the responding muscle in five different reaction time tasks, each requiring sensory discrimination and response selection of varying complexity. In the Choice condition two stimuli were presented, and two separate responses were required. In the two Go-No Go conditions two stimuli were presented, but a response was required to only one or the other of the stimuli. In the two Simple conditions only one stimulus was presented, and one response was required. 3. Under both Choice and Go-No Go conditions, the frequency histogram of the onset latency of the compound muscle action potential for the response to the frequent tone showed a bimodal distribution without overlap, suggesting that there were two distinct types of responder: fast and slow. The comparable histograms for the onset latency of the response to the rare tone also showed a bimodal distribution, but the mean onset latency was prolonged relative to the response to the frequent tone, and the mean separation was less so that the two distributions overlapped each other. 4. Despite the marked difference in response latencies between the fast and slow responders, there was no appreciable difference in cerebral evoked responses between the two groups. Moreover, in response to the frequent tone, all slow responders and, likewise, all fast responders had similar onset latencies of the averaged EMG activity regardless of condition. Nonetheless, fast or slow responders to the frequent tone on one block of trials were also fast or slow responders, respectively, to the rare tone on the same block of trials. 5. These results suggest that two separate sensory discrimination processes are occurring; the first relating to the presence or absence of the frequent (expected) stimulus, and the second relating to the presence or absence of the rare stimulus. The response to each tone can either be generated immediately after that tone is positively identified or, when accuracy is required, can be delayed until both stimuli have been successfully discriminated by the subject.

Acoustic Stimulation↗
PubMed2002

The negative compatibility effect: unconscious inhibition influences reaction time and response selection.

In the negative compatibility effect (NCE) a masked prime arrow, pointing left or right, is followed by an unmasked (visible) target arrow. The task is to press the left or right switch corresponding to the visible arrow. Surprisingly, reaction time is longer (slowed) when the prime and target indicate the same, rather than different, responses. By contrast, the effect of an unmasked prime is positive-opposite to the NCE. This indicates that the NCE is not attributable to incomplete masking; to the extent that the prime is visible, the NCE would be reduced by this positive influence. Thus, the NCE appears to result from unconscious processing of the prime and, in that sense, may be a form of subliminal perception. Additional findings show that the NCE is due to inhibition of a response code, that it is automatic in that it occurs even if the information in the prime and target could be ignored, and that it also influences response selection.

Awareness↗
PubMed2002

Working memory of action: a comparative study of ability to selecting response based on previous action in New World monkeys (Saimiri sciureus and Callithrix jacchus).

Working memory of the outcome of one's own action is important for organizing and learning appropriate behaviors in a given condition. To examine whether non-human primates with different neocortical sizes show different abilities regarding working memory for action, the performance of squirrel monkeys (Saimiri sciureus) and common marmosets (Callithrix jacchus) in a kind of delayed-response task was compared. In this task, subjects were required to select a response based on short-term memory of the outcome of their own prior action, which requires working memory of action. These monkeys have a similar phylogenetic status (i.e. Ceboidea), but the size of the neocortex relative to the rest of the brain (relative size of the neocortex) is quite different. We found that both two species could attend to and remember their own actions and could select a response based on that memory. However, the performance level was higher for squirrel monkeys than for marmosets. These results suggest that non-human primates with differentially developed neocortices have different abilities regarding working memory of action.

Journal Article↗
PubMed2006

Response to selection and evolvability of invasive populations.

While natural selection might in some cases facilitate invasions into novel habitats, few direct measurements of selection response exist for invasive populations. This study examined selection response to changes in salinity using the copepod Eurytemora affinis. This copepod has invaded fresh water from saline habitats multiple times independently throughout the Northern Hemisphere. Selection response to a constant intermediate salinity (5 PSU) was measured in the laboratory for saline source and freshwater invading populations from the St. Lawrence drainage (North America). These populations were reared under three conditions: (1) native salinities (0 or 15 PSU) for at least two generations, (2) 5 PSU for two generations, and (3) 5 PSU for six generations. Full-sib clutches taken from populations reared under these three conditions were split across four salinities (0, 5, 15, and 25 PSU) to determine reaction norms for survival and development time. Contrasts in survival and development time across the three rearing conditions were treated as the selection response. Selection at 5 PSU resulted in a significant decline in freshwater (0 PSU) tolerance for both the saline and freshwater populations. Yet, evolutionary differences in freshwater tolerance persisted between the saline and freshwater populations. The saline and freshwater populations converged in their high-salinity (25 PSU) tolerance, with an increase in the freshwater population and decline in the saline population. Development time did not shift greatly in response to selection at 5 PSU. For all three rearing conditions, the freshwater population exhibited retarded larval development and accelerated juvenile development relative to the saline population. Results from this study indicate that both the saline and freshwater populations exhibit significant responses to selection for a fitness-related trait critical for invasions into a novel habitat.

Animals↗
PubMed2000

Control of response selection by reinforcer value requires interaction of amygdala and orbital prefrontal cortex.

Goal-directed actions are guided by expected outcomes of those actions. Humans with bilateral damage to ventromedial prefrontal cortex, or the amygdala, are deficient in their ability to use information about positive and negative outcomes to guide their choice behavior. Similarly, rats and monkeys with orbital prefrontal or amygdala damage have been found to be impaired in their responses to changing values of outcomes. In the present study, we tested whether direct, functional interaction between the amygdala and the orbital prefrontal cortex is necessary for guiding behavior based on expected outcomes. Unlike control monkeys, rhesus monkeys with surgical disconnection of these two structures, achieved by crossed unilateral lesions of the amygdala in one hemisphere and orbital prefrontal cortex in the other, combined with forebrain commissurotomy, were unable to adjust their choice behavior after a change in the outcome (here, a reduction in the value of a particular reinforcer). The lesions did not affect motivation to work for a food reinforcer, or food preferences, per se. Hence, the amygdala and orbital prefrontal cortex act as part of an integrated neural system guiding decision-making and adaptive response selection.

Accommodation, Ocular↗
PubMed1999

Lesions of the prelimbic-infralimbic cortices in rats do not disrupt response selection processes but induce delay-dependent deficits: evidence for a role in working memory?

Effects of neurotoxic lesions of the prelimbic-infralimbic cortex (PL-IL) were examined in rats performing 2 conditional tasks. PL-IL-lesioned rats showed normal acquisition of a visuospatial conditional discrimination in a Y maze as well as a tone-light conditional discrimination in an operant chamber, indicating that the PL-IL is not necessary for response selection processes. When the working memory load was subsequently increased in the tone-light conditional discrimination, rats with PL-IL lesions showed a delay-dependent disruption of performance. This suggests a role of the PL-IL in some working memory processes. However, the present results, considered along with previous studies, suggest that the PL-IL does not seem to be directly involved in the processes necessary to maintain specific items over a delay period but rather in the planning of forthcoming behavioral responses on the basis of previously acquired information.

Animals↗
PubMed1995

Stimulus preprocessing and response selection in depression: a reaction time study.

Depressed subjects are slower than normal controls in reaction time (RT) tasks. However, it is not clear whether depression affects all stages of information-processing or only some of them. In the present study, this question was addressed by using the additive factor method. Ten inpatients and ten control subjects performed a two-choice visual RT task. Stimulus intensity and stimulus-response compatibility were manipulated. The effect of intensity was similar in both groups whereas the effect of compatibility was larger for the patients than for the controls. This suggests that stimulus preprocessing is unaffected by depression whilst response selection is impaired.

Adult↗
PubMed2004

Response selection difficulty and asymmetrical costs of switching between tasks and stimuli: no evidence for an exogenous component of task-set reconfiguration.

Four task-switching experiments examined the notion of an exogenous component of task-set reconfiguration (i.e., a process needed to shift task set that is not initiated in the absence of a task-associated figuration stimulus). The authors varied the complexity and familiarity of stimulus-response (SR) mapping rules to produce differentially time-consuming reconfiguration demands. Tasks with more complex or less familiar rules did not display increased switch costs, given that stimulus repetitions were excluded from the analysis. These results do not support the idea of exogenous reconfiguration. Moreover, stimulus repetitions inflated task-switch costs and did so disproportionately for tasks with increased response selection difficulty, thereby demonstrating that insufficient control of the sequence of stimuli may yield results that mimic those predicted by exogenous reconfiguration accounts.

Adult↗
PubMed1998

Modulation of the attentional blink by on-line response selection: evidence from speeded and unspeeded task1 decisions.

Two critical target stimuli (T1 and T2) were embedded in a stream of white letters shown on a black background, using a rapid serial visual presentation paradigm (RSVP, 100 msec/item). T1 was a red H or S; T2 was an X or a Y. Performance in a two-alternative discrimination on T2 was impaired when processing of T1 was required--a result often called an attentional blink (AB). In previous work, the response in Task1 has been an unspeeded and delayed response at the end of the trial. Three experiments compared performances in Task2 that depended on whether Task1 required an unspeeded delayed response or a speeded immediate response. A larger AB was found when a speeded response was required. Furthermore, in the speeded conditions, faster responses in Task1 were associated with a smaller and shorter AB effect than were slower responses. The results show that manipulations affecting a relatively late stage of processing--response selection--affect the magnitude and duration of the AB phenomenon. A new central inhibition theory is proposed to account for these results. According to this theory, the AB is similar to the psychological refractory period effect and is caused by central postponement of short-term consolidation of T2.

Adult↗