Towards a new approach to detect sleepiness: Validation of the objective sleepiness scale under simulated driving conditions

The Objective Sleepiness Scale (OSS) was developed to detect and quantify sleepiness on the basis of two direct and reliable sleepiness indicators: EEG and EOG. The present study aims to test whether the OSS can be used to detect sleepiness episodes that impair performance on driving and vigilance tasks accurately and with a good time synchronization. Forty-three healthy volunteers performed monotonous driving sessions on a simulator and the psychomotor vigilance task (PVT) in a normal sleep condition and after partial sleep deprivation. OSS reliability and time synchronization for sleepiness detection were tested on driving (standard deviation of vehicle lateral position and off-road duration) and PVT (reaction time and lapses). Inter-rater reliability of the scale was evaluated by two blinded scorers. Results show that the OSS score indicates higher sleepiness in sleep deprivation conditions (p < 0.001) and with time-on-task. Differences of performance between OSS score calculated with multiple pairwise comparisons, indicate OSS score increase when driving performance (SDLP and off-road duration) decreases (p < 0.001 for comparisons between OSS stages 0 vs 2, 0 vs 3, 1 vs 2 and p < 0.05 for 1 vs 3). Reaction time during PVT is also related to the OSS score (p < 0.05 for OSS values from 0 to 2, 0 to 3, 1 to 2 and 1 to 3). There is no proportional relation between OSS score and performance impairment, but a threshold effect between levels 1 and 2 of the scale is observed. Positive outcomes are also obtained for time synchronization of the OSS assessed on driving performance (p < 0.001 for both SDLP and off-road duration). Finally, inter-rater agreement is found to be considerable. The results allow us to consider using the Objective Sleepiness Scale as a tool for research on sleepiness.     

Acoustic interference in a recognition task

Phonetic or acoustic characteristics of stimuli in recall studies have consistently been shown to generate more interference over short intervals than semantic characteristics. We performed three experiments to determine whether this characteristic also applied to recognition processes over short intervals. Subjects were shown study lists of eight words and were asked to recognize which of those words recurred on subsequent eight-word lists. Delays varied from 0 to 100 s between study and test, with a rehearsal-preventing task inserted during the delays. Phonetic distractors generated greater interference than semantic distractors at all delay levels, and semantic distractors generated greater interference than random distractors. These distractor-type differences were not present in long-term recognition tasks. The deterioration in performance over time was considerably slower in these recognition experiments than in previous recall studies.     

How birds identify species information in song: A pattern recognition approach

Pattern recognition theory (PRT) is a diverse array of models concerned with the recognition of spatial and temporal patterns by humans and machines. We have sought to use the theory to help us understand how passerines identify species information in conspecific song. In this paper, application of PRT provided (a) a tentative model for song recognition, (b) an improved methodology for song playback experiments, and (c) a theoretical analysis of the representation of the temporal structure of song. In each instance, PRT suggested better experiments and more detailed analyses than had been available previously.     

Acoustic similarity and interference in short-term recognition memory: Some results of a decision-theory analysis

The following three studies of single-probe recognition memory set out to show the effect on the signal-detectability measures of d' and β (Tanner and Swets, 1954) of variations in the acoustic similarity of interfering material, which may either precede or follow the item to be remembered (proactive or retroactive interference --PI or RI). The first experiment studies a situation employed by Wickelgren (1966a), who reported that acoustically similar RI substantially reduced d'. It is shown that this effect could have been due to biases in Wickelgren's original designs, and that when a bias-free design is used, the fall in d' is only of borderline significance.

To investigate this problem further, a design was evolved in which two items were presented for memorizing, which varied in acoustic similarity to each other, and (after a distracting task) a probe was presented with one of three questions: Was this the first item of the pair? Was it the second? or, Did it occur in either position? In the first case, recognition-memory with RI of varying acoustic similarity was being studied, and as in the first experiment, it was found that similarity slightly reduced d'. With the second question, PI effects were being studied, and here negligible differences were found. With the third type of question, a “location-free” test, no effects of similarity were found. The last result rules out Posner's (1967) “acid-bath” explanation of similarity effects in interference: an explanation in terms of “differentiation” (or “filtering”) was also invalidated by the results of a third experiment, in which the same effects were found even though similarity varied only between stimulus items and interference, and not between these and the probe. Wickelgren's (1966b) associative model appears to have least difficulty in accommodating these results, though even this needs certain ad hoc assumptions to be able to do so.     

Face to face with an enactive approach: A sensorimotor account of face detection and recognition

The enactive approach to perception describes experience as a temporally extended activity of skillful engagement with the environment. This paper pursues this view and focuses on prosopagnosia both for the light that the theory can throw on the phenomenon, and for the critical light the phenomenon can throw on the theory. I argue that the enactive theory is insufficient to characterize the unique nature of experience specific to prosopagnosic subjects. There is a distinct difference in the overall process of detection (with respect to eye movement sequence) of familiar and unfamiliar faces in prosopagnosia; in contrast, normal subjects use the same scanning strategy when exploring both kinds of faces despite an obvious difference in qualitative character. In light of this limitation I outline a supplemental view basing sensorimotor contingencies upon the establishment and reaffirmation of regularities within the organism as it engages with the environment.     

The Great Eight competencies: a criterion-centric approach to validation

The author presents results of a meta-analysis of 29 validation studies (N=4,861) that uses the Great Eight competency factors (Kurz & Bartram, 2002) as the criterion measurement framework. Predictors of the Great Eight competencies based only on personality scales show moderate to good correlations with line-manager ratings for all 8 of the competencies. On their own, ability tests correlate with 4 of the 8 competencies, and together ability and personality data yield operational validities ranging from 0.20 to 0.44 for the 8 competencies. Operational validities for aggregated predictors with aggregated criteria were estimated to be 0.53. The value of differentiating the criterion space and of relating predictor variables to criterion variables in a one-to-one fashion is discussed.     

Visual pattern recognition: Size preprocessing re-examined

Template theories of visual pattern recognition assume the operation of preprocessing routines to deal with irrelevancies such as discrepancies in stimulus size. In three experiments where size was an irrelevant dimension, observers classified pairs of forms as either “same” or “different”. In Experiment I, the classification “different” was required when the stimuli shared the same form but a different orientation, and “same” when the stimuli shared the same form and orientation. Under these conditions RT was an increasing function of the magnitude of the size disparity between stimuli with equal slopes for “same” and “different” judgements. In Experiment II, “different” classifications were made to stimuli that had different forms, and “same” to figures with the same form. This stimulus set produced a size disparity function that interacted with response type; “different” responses had a shallower slope. Experiment III consisted of a mixed stimulus set drawn from both Experiment I and II. Stimuli that produced additive effects of size disparity and response type in Experiment I now produced an interaction between these two factors similar to the one observed in Experiment II. The results of these experiments are interpreted as evidence that previous contradictory results reported in the literature stem from differences in the way the stimulus set is constructed, and that size transformations can not be a necessary operation, at least when “different” judgements are made. The results are problematic for the view that size disparity effects in matching tasks are easily interpretable in terms of a primitive size normalization stage that precedes any comparison operations.     

Acoustic confusion of digits in memory and recognition

It has been shown that, contrary to current opinion, digits do not confuse arbitrarily and that similar patterns of confusion are observed in memory and auditory recognition tasks. Two alternative measures of stimulus similarity are compared.     

Searching for answers: expert pattern recognition and planning

Does expertise mostly stem from pattern recognition or look-ahead search? van Opheusden et al. contribute to this important debate in cognitive psychology and artificial intelligence (AI) with a multi-method, multi-experiment study and a new model. Using a novel, relatively simple board game, they show that players increase depth of search when improving their skill.     

Mechanisms and neural basis of object and pattern recognition: a study with chess experts

Comparing experts with novices offers unique insights into the functioning of cognition, based on the maximization of individual differences. Here we used this expertise approach to disentangle the mechanisms and neural basis behind two processes that contribute to everyday expertise: object and pattern recognition. We compared chess experts and novices performing chess-related and -unrelated (visual) search tasks. As expected, the superiority of experts was limited to the chess-specific task, as there were no differences in a control task that used the same chess stimuli but did not require chess-specific recognition. The analysis of eye movements showed that experts immediately and exclusively focused on the relevant aspects in the chess task, whereas novices also examined irrelevant aspects. With random chess positions, when pattern knowledge could not be used to guide perception, experts nevertheless maintained an advantage. Experts' superior domain-specific parafoveal vision, a consequence of their knowledge about individual domain-specific symbols, enabled improved object recognition. Functional magnetic resonance imaging corroborated this differentiation between object and pattern recognition and showed that chess-specific object recognition was accompanied by bilateral activation of the occipitotemporal junction, whereas chess-specific pattern recognition was related to bilateral activations in the middle part of the collateral sulci. Using the expertise approach together with carefully chosen controls and multiple dependent measures, we identified object and pattern recognition as two essential cognitive processes in expert visual cognition, which may also help to explain the mechanisms of everyday perception.     

Situational approach to assessment of guilt: Development and validation of a self-report measure

The present research developed and evaluated a self-report measure of guilt that encompassed diverse, typical guilt experiences. Behavior-analytic procedures were employed to construct the Situational Guilt Scale (SGS), in which 22 items assessed anticipated guilt feelings for a wide range of naturally occurring specific situations. The SGS was administered to young-adult college students (mean age, 24 years), along with measures of guilt in traditional moral contexts, depressive tendencies, and socially desirable responding. A test-retest study of the SGS was separately conducted. Results indicated that SGS scores had statisfactory internal consistencies and considerable stability. Correlational findings and comparisons of SGS scores in a typology of depressive experience showed relationships of SGS guilt scores with dependent and self-critical tendencies and support the validity of the measure. The findings and utility of the SGS are discussed.Grant 13487 from the PSC-CUNY Research Award Program of the City University of New York provided support for this project. The Committee on Research Computing of the City University of New York funded the use of computer facilities.     

Modeling hippocampal and neocortical contributions to recognition memory: a complementary-learning-systems approach

The authors present a computational neural-network model of how the hippocampus and medial temporal lobe cortex (MTLC) contribute to recognition memory. The hippocampal component contributes by recalling studied details. The MTLC component cannot support recall, but one can extract a scalar familiarity signal from MTLC that tracks how well a test item matches studied items. The authors present simulations that establish key differences in the operating characteristics of the hippocampal-recall and MTLC-familiarity signals and identify several manipulations (e.g., target-lure similarity, interference) that differentially affect the 2 signals. They also use the model to address the stochastic relationship between recall and familiarity and the effects of partial versus complete hippocampal lesions on recognition.     

Coping through emotional approach: scale construction and validation

Four studies demonstrate the psychometric adequacy and validity of scales designed to assess coping through emotional approach. In separate undergraduate samples, exploratory and confirmatory factor analyses of dispositional (Study 1) and situational (Study 3) coping item sets yielded 2 distinct emotional approach coping factors: emotional processing (i.e., active attempts to acknowledge and understand emotions) and emotional expression. The 2 scales yielded high internal consistency and test-retest reliability, as well as convergent and discriminant validity. A study (Study 2) of young adults and their parents established the scales' interjudge reliabilities. Longitudinal (Study 3) and experimental (Study 4) research supported the predictive validity of the emotional approach coping scales with regard to adjustment to stressful encounters. Findings highlight the utility of functionalist theories of emotion as applied to coping theory.     

Tactile letter recognition: Pattern duration and modes of pattern generation

Measurements were made of the ability of subjects to identify vibrotactile patterns presented to their fingertips. The patterns were letters of the alphabet generated on the tactile display of the Optacon. Five different modes of pattern generation were examined. Two of the modes, static and scan, involved full-field presentations of the letters. In the remaining three modes, patterns were generated by presenting parts of the letters sequentially. In one mode, the letters were exposed by a slit passing across them. In the other two modes, the patterns were generated as though the letter were being drawn on the skin. Performance in all five modes was examined as a function of pattern duration, with durations ranging from 4 to 1,000 msec. Increasing duration, up to 400 msec, resulted in generally improved performance, although the functions relating performance and duration differed according to the mode of presentation. Contrary to previous results, the static mode produced the best overall performance level. Some possible reasons for the disagreement between the present results and previous results and some models of cutaneous pattern recognition are discussed.     

Feigned depression and feigned sleepiness: a voice acoustical analysis

We sought to profile the voice acoustical correlates of simulated, or feigned depression by neurologically and psychiatrically healthy control subjects. We also sought to identify the voice acoustical correlates of feigned sleepiness for these same subjects. Twenty-two participants were asked to speak freely about a cartoon, to count from 1 to 10, and to sustain an "a" sound for approximately 5s. These exercises were completed three times (within the same testing session) with three differing sets of instructions to the participants. These three conditions were presented in pseudo-random order to control for any order effects, and all subjects were na?ve to the intended purpose of this study. For all three conditions, mean speaking rates and pitch ranges were calculated. A series of paired t tests showed significant differences in the speaking rates (counting numbers and free-speech exercises) between the 'normal' and feigned sleepy conditions, and between the normal and feigned depression conditions, but not between the 'sleepy' and 'depressed' conditions. The results for pitch range, for all speech exercises, were not different between the normal and either the feigned depression or feigned sleepiness conditions. These results indicate that persons feigning depression and sleepiness demonstrate some level of conscious control of their speech rate, but they did not convincingly alter their pitch ranges while feigning depression or sleepiness.