A signal-detection analysis of fast-and-frugal trees.

Models of decision making are distinguished by those that aim for an optimal solution in a world that is precisely specified by a set of assumptions (a so-called “small world”) and those that aim for a simple but satisfactory solution in an uncertain world where the assumptions of optimization models may not be met (a so-called “large world”). Few connections have been drawn between these 2 families of models. In this study, the authors show how psychological concepts originating in the classic signal-detection theory (SDT), a small-world approach to decision making, can be used to understand the workings of a class of simple models known as fast-and-frugal trees (FFTs). Results indicate that (a) the setting of the subjective decision criterion in SDT corresponds directly to the choice of exit structure in an FFT; (b) the sensitivity of an FFT (measured in d′) is reflected by the order of cues searched and the properties of cues in an FFT, including the mean and variance of cues' individual d′s, the intercue correlation, and the number of cues; and (c) compared with the ideal and the optimal sequential sampling models in SDT and a majority model with an information search component, FFTs are extremely frugal (i.e., do not search for much cue information), highly robust, and well adapted to the payoff structure of a task. These findings demonstrate the potential of theory integration in understanding the common underlying psychological structures of apparently disparate theories of cognition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A field study of the forensic use of hypnosis.

Conducted a field study of selected cases from police files in which hypnosis had been used as a memory aid. In a detailed analysis of 7 of the 41 cases, scoring revealed that hypnosis almost tripled the amount of information that witnesses provided compared with a standard interview (conducted prior to the hypnosis interview) with no loss in accuracy. Interviews with police hypnotists and investigators revealed that in addition to hypnosis the procedure included known memory aids. It is concluded that the cognitive instructions incorporated in the hypnotic interview may provide the basis for improved recall. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhancing visual memory: Trying hypnosis, trying imagination, and trying again.

Tested visual recall memory of high (n?=?24) and low (n?=?24) hypnotizable undergraduates (screened under the Harvard Group Scale of Hypnotic Sensibility and the Stanford Hypnotic Sensibility Scale) for black and white line drawings of common objects in either hypnosis, imagination, or control conditions. Memory performance in terms of both correct and incorrect items increased appreciably across the recall tests. Neither hypnosis nor imagination enhanced recall beyond that of normal repeated testing. Hypnotizability was not related to the amount of correct material recalled but was related to the amount of incorrect material reported. High hypnotizable Ss in the hypnosis condition were more likely than other Ss to confidently rate the incorrect material as correct. Findings are discussed in terms of the impact of hypnosis on and the relevance of hypnotizability to enhancing visual memory. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

UCS intensity and instructional set in classical eyelid conditioning: Discrimination conditioning and signal-detection analysis.

Conducted discrimination eyelid conditioning at 2 UCS intensities under inhibitory, neutral, and facilitatory instructional sets, in a experiment involving 144 undergraduates in 6 groups. Instructional set yielded receiver operating characteristic curves that were reasonably straight lines on a normal deviate plot. The tentative conclusion from signal-detection theory of an equal discriminability function across instructional sets was contrasted with 4 indices of discrimination, indicating significant but mutually contradictory changes in discrimination as a function of instructional set. Discrimination differences were produced by UCS intensity, particularly under the neutral instructions. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A signal detection analysis of hypnotically induced narrowing of the peripheral visual field.

Narrowing of the peripheral visual field ("tunnel vision") was suggested to 4 hypnotized Ss and to 4 Ss simulating hypnosis. Changes in light thresholds in the "blind" portion of the periphery were observed and analyzed using a signal detection approach and were attributed to changes in sensitivity rather than to criterion shifts. Ss simulating hypnosis produced results that were statistically indistinguishable from those of hypnotized Ss. Results are discussed in terms of S attention, and theoretical and practical implications of the results for research in hypnosis and hysteria, for the appropriateness of signal detection theory, and for visual field testing in general are pointed out. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cerebral laterality and depression: Differences in perceptual asymmetry among diagnostic subtypes.

Examined the influence of diagnostic subtype of depression on perceptual asymmetry for dichotic listening and visual tachistoscopic tasks. A total of 65 unmedicated patients with major depressive disorders and 30 normal controls were tested on a verbal and nonverbal task in each modality. Patients diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) with melancholia had abnormal perceptual asymmetry for dichotic nonsense syllable and complex tone tasks. In contrast, patients having a nonmelancholic "atypical depression" (reactivity of mood with preserved pleasure capacity and associated features) did not differ from normal controls on these tasks, but had an increased incidence of left handedness. Bipolar depression (history of hypomania) differed from unipolar depression in showing abnormal perceptual asymmetry for a tachistoscopic dot enumeration task. Alterations of perceptual asymmetry in melancholia and bipolar depression were consistent with hypothesized right hemisphere dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory and hypnosis: Implications for the use of forensic hypnosis.

I review arguments regarding hypnosis in forensic investigations, offer procedures of a nonhypnotic nature to enhance memory recall, and suggest guidelines for hypnosis in criminal cases. The effects of hypnosis on memory, as well as the concomitant dangers regarding those effects, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention in schizophrenia: An analysis of selectivity in the functional visual field.

Presents a visual–spatial approach to the study of attention dysfunction. The hypotheses of broadened and narrowed attention were tested by comparing peripheral visual discrimination of 10 acute schizophrenic and 11 chronic schizophrenic inpatients and 16 normal Ss (hospital staff) within 2 regions of the functional visual field. Pairs of visual stimuli were presented at 4 display angles. Measures of response accuracy, response latency, and latency of eye movement of peripheral stimuli were obtained. Results indicate that acute schizophrenics generally discriminated peripheral signals more accurately than chronic schizophrenics or normals. Normals discriminated signals more accurately than chronic schizophrenics. Results suggest the differential use of selective strategies. Limitations in the use of peripheral information among chronic schizophrenics implies a reduction in the amount of information transmitted in a selective act and a reduction in the economy of selective activities. In contrast to normals, acute schizophrenics utilized more efficient selective strategies over a greater spatial area, implying greater transmission of information within discrete selective acts. Results also indicate that schizophrenics initiated eye movements earlier than normals and that response latency was greater for acute schizophrenics than for normals. Results are interpreted as providing partial support for P. H. Venable's (1964) theory of input dysfunction. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhanced visual memory during hypnosis as mediated by hypnotic responsiveness and cognitive strategies.

Investigated the hypothesis that hypnosis has an enhancing effect on imagery processing, as mediated by hypnotic responsiveness and cognitive strategies. Four experiments with 112 undergraduates compared performance of low and high, or low, medium, and high hypnotically responsive Ss in waking and hypnosis conditions on a successive visual memory discrimination task that required detecting differences between successively presented picture pairs in which 1 member of the pair was slightly altered. Results reveal that hypnotically responsive Ss showed enhanced performance during hypnosis, whereas nonresponsive Ss did not. Hypnotic responsiveness correlated with enhanced performance during hypnosis only. RT was not affected by hypnosis. Ss reported enhanced imagery vividness on the self-report Vividness of Visual Imagery Questionnaire during hypnosis. Two cognitive strategies appeared to mediate visual memory performance: (a) detail strategy, which involved the memorization and rehearsal of individual details for memory, and (b) holistic strategy, which involved looking at and remembering the whole picture with accompanying imagery. Both lows and highs reported similar detail-oriented strategies during waking; only highs shifted to a significantly more holistic strategy during hypnosis. (86 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experiential analysis of hypnosis: Some new observations on hypnotic phenomena.

10 Ss who were assessed on the Harvard Group Scale of Hypnotic Susceptibility as being highly susceptible to hypnosis were shown videotaped versions of their previous hypnotic sessions in the presence of an independent inquirer who attempted to foster Ss' personal comments on their own experiences. A special method of inquiry called the "experiential analysis technique" was constructed to study Ss' recall, which was examined for fantasy involvement, rapport, and individual modes of cognition. Data from the application of the method indicate the idiosyncratic ways in which Ss interpret routine suggestions, the degree to which they become personally involved with the hypnotist, and 3 distinct modes of cognizing, which were labeled "concentrative-cooperative," "cognitive-independent," and "cognitive-constructive." (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nonlinear analysis of visual evoked potentials elicited by color stimulation

The relationship between chromatically modulated stimuli and visual evoked potentials (VEPs) was considered. VEPs of normal subjects elicited by chromatically modulated stimuli were measured under several color adaptations, and their binary kernels were estimated. Up to the second-order, binary kernels obtained from VEPs were so characteristic that the VEP-chromatic modulation system showed second-order nonlinearity. First-order binary kernels depended on the color of the stimulus and adaptation, whereas second-order kernels showed almost no difference. This result indicates that the waveforms of first-order binary kernels reflect perceived color (hue). This supports the suggestion that kernels of VEPs include color responses, and could be used as a probe with which to examine the color visual system.     

Effects of divided attention on encoding and retrieval processes in human memory: further support for an asymmetry

Despite a tradition in cognitive psychology that views encoding and retrieval processes in human memory as being similar, F. I. M. Craik, R. Govoni, M. Naveh-Benjamin and N. D. Anderson (1996) have recently shown that notable differences exist between the 2 when divided-attention manipulations are used. In this article, the authors further examined this asymmetry by using several manipulations that changed task demands at encoding and retrieval. The authors also used a secondary-task methodology that allowed a microlevel analysis of the secondary-task costs associated with encoding and retrieval. The results illustrated the resiliency of retrieval processes to manipulations involving different task demands. They also indicated different loci of attention demands at encoding and retrieval. The authors contend that whereas encoding processes are controlled, retrieval processes are obligatory but do require attentional resources for their execution.     

Group feedback analysis: A method of field research.

"Group feedback analysis" combines a number of features from nomothetic and idiographic methods, thus overcoming some of the limitations of the mailed questionnaire. Certain advantages were described by reference to a number of research problems. Group feedback analysis has 3 interrelated stages: (1) individual research instruments are administered to a group of Ss; (2) some, or all, of the results from Stage 1 are fed back to the group as means and deviations; and (3) a discussion based on feedback of results is stimulated, recorded, and later content analyzed. Moving from unstructured to focused questioning, the investigator obtains a varied amount of information which acts both as a check and extension of the results obtained from Stage 1. (46 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The nature of hypnosis: Artifact and essence.

An experimental analysis of the part played by preconceived ideas about the phenomenon and the motivation of the S in hypnosis. The difference between genuine and feigned trances is discussed along with a discussion of the theoretical application of the present and previous research. 33 refs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial processing and hemispheric asymmetry. Contributions of the transient/magnocellular visual system

Right-handed observers were presented with stimuli consisting of a line and two horizontally separated dots. A categorical spatial task required observers to indicate whether the dots were above or below the line, and a coordinate spatial task required observers to indicate whether the line could fit into the space between the two dots. For the coordinate task, reaction time was faster when the stimuli were presented to the left visual field (right hemisphere) than when the stimuli were presented to the right visual field (left hemisphere). The opposite hemispheric asymmetry was obtained for the categorical task. In addition, coordinate spatial processing took longer with stimuli presented on a red background than with stimuli presented on a green background. The opposite hemispheric asymmetry was obtained for the categorical task. In addition, coordinate spatial processing took longer with stimuli presented on a red background than with stimuli presented on a green background. The opposite trend characterized categorical spatial processing. Because the color red attenuates processing in the transient/magnocellular visual pathway, these results suggest that coordinate spatial processing is more dependent on the transient/magnocellular pathway than is categorical spatial processing. However, manipulations of color condition had no effect on visual field (hemispheric) asymmetries, suggesting that the two hemispheres rely on the same visual information and on the same computational mechanisms as each other-although they do not always use that information with equal efficiency.     

A spectral analysis of cognitive and personality variables in hypnosis: Empirical disconfirmation of the two-factor model of hypnotic responding.

The two-factor model of hypnotic responding posits that ability or trait variables are more important than contextual variables in producing responses to difficult hypnotic suggestions, whereas contextual variables such as attitudes and expectancies are more important than trait variables in predicting responses to easier suggestions. In three separate data sets, responses to suggestions of varying difficulty were correlated with absorption, fantasy proneness, dissociation, attitudes toward hypnosis, and hypnotic response expectancy. Although the results of these analyses were not consistent across data sets, all significant findings were in the opposite direction of that predicted by two-factor theorists. In general, expectancy was the strongest correlate of hypnotic response, especially for highly responsive participants and for difficult suggestions. It is concluded that despite the attractiveness of the two-factor model, repeated attempts to replicate its empirical base have been unsuccessful. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Allocation of attention in the visual field.

Investigated in 2 experiments whether attentional resources can be simultaneously allocated to several locations in a visual display, whether the mode of processing (serial or parallel) can be switched within a trial, and the nature of the costs when attentional resouces are concentrated on an invalid location. In each of the experiments, 6 college students were required to determine which of 2 target letters was present in 8-letter circular displays. In precue conditions, a primary and a secondary target location were designated 150 msec before target onset by an indicator that varied in validity. In the control conditions no cue was provided. Exp II verified several assumptions that had been made in interpreting the data of Exp I. Modifications in J. Jonides's (see record 1984-08558-001) 2-process model are suggested in terms of a zoom lens model of attentional resources. Instead of 2 alternative processing modes, attentional resources are seen as capable of distribution over the visual field, but with low resolving power, or as continuously constricting to small portions of the visual field with a concomitant increase in processing power. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A divergent view of convergence in hypnosis research.

N. P. Spanos and T. X. Barber's (see record 1975-00161-001) article on convergence in hypnosis research exudes an optimism that is misleading. This illusory confidence involves 2 factors that mediate response to hypnotic suggestions: (1) willingness by the S to cooperate and (2) a shift in cognitive orientation from an objective perspective to one of involvement in suggestion-related imaginings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lateral eye movements and hemispheric asymmetry: A critical review.

Eye movements to the left or right have been hypothesized to reflect activation of the cerebral hemisphere contralateral to the direction of gaze. This hypothesis was tested by comparing the direction of lateral eye movements (LEMs) following questions designed to engage the left or right hemisphere. The evidence from such studies was equivocal. Fewer than half found the predicted pattern of more right LEMs for left-hemisphere questions, and conceptual and methodological ambiguities in the questions, scoring, and experimental situation made interpretation of these studies difficult. In addition, findings showing more upward eye movements and more stares for right-hemisphere questions cannot be incorporated into the hemispheric asymmetry model of LEMs. Studies on individual differences in LEM patterns indicated a fair degree of stability and some consistency in their correlates. However, since "right" and "left movers" do not differ in verbal or spatial abilities, there is little justification for linking LEM patterns with "hemisphericity." It is concluded that further research on the relationship between directional ocular events and cognitive-affective processes is required before inferences about hemispheric function can be drawn from studies of lateral eye movements. (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)