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2.
Neuron ; 32(3): 537-51, 2001 Nov 08.
Article in English | MEDLINE | ID: mdl-11709163

ABSTRACT

The brain circuitry processing rewarding and aversive stimuli is hypothesized to be at the core of motivated behavior. In this study, discrete categories of beautiful faces are shown to have differing reward values and to differentially activate reward circuitry in human subjects. In particular, young heterosexual males rate pictures of beautiful males and females as attractive, but exert effort via a keypress procedure only to view pictures of attractive females. Functional magnetic resonance imaging at 3 T shows that passive viewing of beautiful female faces activates reward circuitry, in particular the nucleus accumbens. An extended set of subcortical and paralimbic reward regions also appear to follow aspects of the keypress rather than the rating procedures, suggesting that reward circuitry function does not include aesthetic assessment.


Subject(s)
Beauty , Face , Magnetic Resonance Imaging , Motivation , Reward , Adult , Analysis of Variance , Brain/physiology , Brain Mapping/methods , Female , Humans , Magnetic Resonance Imaging/methods , Male
3.
Acta Psychol (Amst) ; 108(2): 187-207, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11569762

ABSTRACT

The current work takes a general perspective on the role of time in decision making. There are many different relationships and interactions between time and decision making, and no single summary can do justice to this topic. In this paper we will describe a few of the aspects in which time and decision making are interleaved: (a) temporal perspectives of decisions--the various temporal orientations that decision-makers may adopt while making decisions, and the impact of such temporal orientations on the decision process and its outcomes; (b) time as a medium within which decisions take place--the nature of decision processes that occur along time; (c) time as a resource and as a contextual factor--the implications of shortage in time resources and the impact of time limits on decision making processes and performance; (d) time as a commodity--time as the subject matter of decision making. The paper ends with a few general questions on the role of duration in decision making.


Subject(s)
Choice Behavior , Decision Making , Time , Humans
4.
Psychol Sci ; 12(2): 157-62, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11340926

ABSTRACT

Sets of similar objects are common occurrences--a crowd of people, a bunch of bananas, a copse of trees, a shelf of books, a line of cars. Each item in the set may be distinct, highly visible, and discriminable. But when we look away from the set, what information do we have? The current article starts to address this question by introducing the idea of a set representation. This idea was tested using two new paradigms: mean discrimination and member identification. Three experiments using sets of different-sized spots showed that observers know a set's mean quite accurately but know little about the individual items, except their range. Taken together, these results suggest that the visual system represents the overall statistical, and not individual, properties of sets.


Subject(s)
Choice Behavior , Discrimination, Psychological , Pattern Recognition, Visual , Set, Psychology , Adult , Humans , Male , Models, Psychological , Visual Perception
5.
J Exp Psychol Appl ; 6(2): 130-47, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10937317

ABSTRACT

The average probability estimate of J > 1 judges is generally better than its components. Two studies test 3 predictions regarding averaging that follow from theorems based on a cognitive model of the judges and idealizations of the judgment situation. Prediction 1 is that the average of conditionally pairwise independent estimates will be highly diagnostic, and Prediction 2 is that the average of dependent estimates (differing only by independent error terms) may be well calibrated. Prediction 3 contrasts between- and within-subject averaging. Results demonstrate the predictions' robustness by showing the extent to which they hold as the information conditions depart from the ideal and as J increases. Practical consequences are that (a) substantial improvement can be obtained with as few as 2-6 judges and (b) the decision maker can estimate the nature of the expected improvement by considering the information conditions.


Subject(s)
Decision Making , Judgment , Probability Learning , Adult , Humans , Motivation
7.
J Exp Psychol Gen ; 129(4): 508-23, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11142865

ABSTRACT

Research on sequences of outcomes shows that people care about features of an experience, such as improvement or deterioration over time, and peak and end levels, which the discounted utility model (DU) assumes they do not care about. In contrast to the finding that some attributes are weighted more than DU predicts, Kahneman and coauthors have proposed that there is one feature of sequences that DU predicts people should care about but that people in fact ignore or underweight: duration. In this article, the authors extend this line of research by investigating the role of conversational norms (H. P. Grice, 1975), and scale-norming (D. Kahneman & T. D. Miller, 1986). The impact of these 2 factors are examined in 4 parallel studies that manipulate these factors orthogonally. The major finding is that response modes that reduce reliance on conversational norms or standard of comparison also increase the attention that participants pay to duration.


Subject(s)
Decision Making , Mental Processes , Models, Psychological , Adult , Female , Humans , Male , Time Factors
8.
J Exp Psychol Gen ; 129(4): 524-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11142866

ABSTRACT

Recent research has demonstrated that people care about the temporal relationships within a sequence of experiences. There is considerable evidence that people pay particular attention to the way experiences improve or deteriorate over time and to their maximum (peak) and final values. D. Kahneman and coauthors suggested in earlier articles that people ignore or severely underweight duration (which they referred to as duration neglect). In the preceding article, D. Ariely and G. Loewenstein (2000) challenged the generalizability of these findings and their normative implications. In the current commentary, D. Ariely, D. Kahneman, and G. Loewenstein jointly examine the issue to provide a better understanding of what they feel they have learned from this literature and to discuss the remaining open questions.


Subject(s)
Decision Making , Models, Psychological , Humans , Mental Processes , Time Factors
9.
Plast Reconstr Surg ; 100(1): 84-5, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9207662

ABSTRACT

Myxoid liposarcoma of the head and neck is an extremely rare entity. The scalp region represents a risk factor to the patient because the diagnosis is usually made late, and the surgeon must have a high index of suspicion for this entity because suctioning the tumor without taking a biopsy further delays an accurate diagnosis.


Subject(s)
Liposarcoma, Myxoid/pathology , Scalp/pathology , Skin Neoplasms/pathology , Biopsy , Humans , Liposarcoma, Myxoid/surgery , Male , Middle Aged , Reoperation , Scalp/surgery , Skin Neoplasms/surgery , Skin Transplantation
10.
J Clin Gastroenterol ; 23(3): 211-3, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8899504

ABSTRACT

Air within the wall of the stomach is an extremely rare situation with an obscure etiology and a high mortality (43%); only 49 cases have previously been reported in the English language. We present another case, review the relevant literature, and discuss possible-etiologies and treatment.


Subject(s)
Emphysema/diagnostic imaging , Stomach Diseases/diagnostic imaging , Emphysema/etiology , Emphysema/therapy , Humans , Male , Middle Aged , Stomach Diseases/etiology , Stomach Diseases/therapy , Suction , Tomography, X-Ray Computed
11.
J Opt Soc Am A Opt Image Sci Vis ; 13(4): 681-8, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8867752

ABSTRACT

We studied whether the blur/sharpness of an occlusion boundary between a sharply focused surface and a blurred surface is used as a relative depth cue. Observers judged relative depth in pairs of images that differed only in the blurriness of the common boundary between two adjoining texture regions, one blurred and one sharply focused. Two experiments were conducted; in both, observers consistently used the blur of the boundary as a cue to relative depth. However, the strength of the cue, relative to other cues, varied across observers. The occlusion edge blur cue can resolve the near/far ambiguity inherent in depth-from-focus computations.


Subject(s)
Depth Perception/physiology , Refractive Errors/physiopathology , Vision, Ocular/physiology , Humans
12.
Vision Res ; 36(3): 361-72, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8746226

ABSTRACT

The area over which boundary information contributes to the determination of the center of an extended object was inferred from results of a bisection task. The object to be bisected was a rectangle with two long sinusoidally modulated sides, i.e. a wiggly rectangle. The spatial frequency and amplitude of the edge modulation were varied. Two object widths were tested. The modulation of the perceived center approximately equaled that of the edges at very low edge modulation frequencies and decreased in amplitude with increasing edge modulation frequency. The edge modulation had a greater modulating effect on the perceived center for the narrower object than for the wider object. This scaling with object width didn't follow perfect zoom invariance but was precisely matched by the scaling of the bisection threshold with width, strongly supporting the idea that the same mechanism determines both the location of the perceived center for these stimuli and its variance. We propose that this mechanism is the linking of object boundaries at a scale determined by the object width.


Subject(s)
Form Perception/physiology , Size Perception/physiology , Humans , Judgment , Sensory Thresholds/physiology
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