The unconscious perception of the meaning of verbal stimuli.

"The hypothesis was investigated that the meaning of a verbal stimulus may be responded to without prior recognition of the stimulus. Four treatment groups were employed of 16 Ss each. The experimental procedure used… consisted essentially of obtaining the S's guesses to a series of verbal stimuli, dichotomized in affective connotation, which were presented at or slightly below the S's previously determined absolute threshold… . there was no evidence that the Ss could make better than chance matches… . It was concluded that no evidence was obtained that Ss respond to the meaning of verbal stimuli prior to recognition of the stimuli." From Psyc Abstracts 36:02:2HL32F. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Illusory" illusory conjunctions: The conjoining of features of visual and imagined stimuli.

The question of whether illusory conjunctions would occur with visual mental imagery was investigated. In 4 experiments, participants were tachistoscopically presented displays of geometrical figures (varying in shape, color, and solidity) flanked by 2 digits. For half of the trials, participants imagined one of the figures in the display. Illusory conjunctions occurred between the features of the physical (cued) and imagined figures, which suggests that imagery influences perception at the level of visual processing at which features are combined. Moreover, the conjunction errors induced by an imagined figure were similar to those induced by a physical figure with the same features. The pattern of errors could not be accounted for by guessing. Together, these findings support the view that there can be correspondence between visual imagery and visual perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of structure in infant visual pattern perception.

In Exp 1, 15 infants (aged 4 mo 2 days to 5 mo 9 days) were presented with a symmetrical (SYP) and an asymmetrical pattern (ASP), using a paired comparison preference technique. The SYPs represented vertical, horizontal, 2-fold, and 4-fold symmetry (SYM). 15 infants (aged 3 mo 29 days, to 5 mo 16 days) in Exp 2 additionally viewed patterns with 8-fold SYM, using the same procedure as Exp 1. Ss preferred patterns with multiple axes of bilateral SYM relative to ASPs. Also, vertically oriented single axis bilateral SYM was more salient than horizontally oriented SYM. The perception of structure appears to be basic to the functioning of the visual system. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of inducer polarity and contrast on the perception of illusory figures

A study designed to determine how inducer-surround contrast and inducer polarity affect the contour clarity and the lightness of illusory figures is reported. Using magnitude estimation procedures, ten naive subjects rated both the contour clarity and the lightness of Kanizsa squares. The magnitude of the inducer-surround contrast and the inducer polarity (all-black, all-white, or black-and-white) were varied randomly on each trial. The data indicate that contour clarity increases with contrast at the same rate across polarity conditions but that contour clarity at any given contrast level depends significantly on polarity. Contour clarity judgments were significantly lower when the inducers were all-white than when the inducers were all-black or black-and-white, and significantly greater in the 'mixed' polarity case (black-and-white inducers) than in the 'same' polarity case (the average of the all-black and all-white inducer conditions). Inducer contrast and polarity significantly affected the lightness of the illusory figure in a manner consistent with simultaneous spatial contrast. Also, for a given increment in contrast, contour clarity altered significantly more than surface lightness, regardless of inducer polarity. The findings suggest that the mechanism which mediates boundary formation is sensitive to the direction of contrast, and that the boundary formation mechanism is more sensitive than the surface lightness mechanism to changes in contrast magnitude. The results are considered within the context of neural network models of form perception.     

A functional role for illusory colour spreading in the control of focused visual attention

In cases of modal completion, illusory colour spreading fills in the surface of a subjectively completed shape. In amodal completion, shapes are likewise completed, but now behind a partial occluder, so that filling in of illusory colour to the completed region no longer arises. We consider the possible functional effects that illusory colour spreading may exert on later stages of vision, and argue that comparisons of modal with amodal completion may be particularly revealing in this regard. It is hypothesised that cueing the inducers of a modally completed object should attract attention to the entire object, including the completed region, owing to the colour spreading there. By contrast, changes to the inducers of a comparable amodally completed object should only attract attention to the inducing regions themselves. This prediction is supported by findings in two experiments with stereoscopic displays, with control conditions ruling out nonattentional accounts, or explanations in terms of stereo disparity alone rather than the presence versus absence of illusory colour. We argue that illusory colours get filled in at quite early stages during modal completion, precisely so that later stages of vision, such as focused attention, can then be driven by the completed regions in the same way as for uniform regions that are physically present in the image.     

Transference in social perception: the role of chronic accessibility in significant-other representations

Research has shown that the activation and application of a significant-other representation to a new person, or transference, occurs in everyday social perception (S. M. Andersen & A. Baum, 1994; S. M. Andersen & S. W. Cole, 1990). Using a combined idiographic and nomothetic experimental paradigm, two studies examined the role of chronic accessibility of significant-other representations in transference. After learning about 4 fictional people, 1 of whom resembled a significant other, participants' recognition memory was assessed. Both studies showed greater false-positive memory in the significant-other condition, relative to control, even in the absence of priming. Study 2 showed that although the effect was greater when the significant-other representation was concretely applicable to the target information, it occurred even when no such applicability was present. Results implicate the chronic accessibility of significant-other representations in transference.     

Covariation of activity in visual and prefrontal cortex associated with subjective visual perception

Visual areas of the occipitotemporal pathway are thought to be essential for the conscious perception of objects, but the contribution of other cortical regions and the neural mechanisms leading to the awareness of a visual stimulus remain unclear. By using functional MRI in humans exposed to bistable viewing conditions, subjective visual perception was related to covariation of activity in multiple extrastriate ventral, parietal, and prefrontal cortical areas. The coordination of activity among these regions was not linked to external sensory or motor events; rather, it reflected internal changes in perception and varied in strength with the frequency of perceptual events, suggesting that functional interactions between visual and prefrontal cortex may contribute to conscious vision. Because similar cortical systems have been implicated in short-term memory and motor planning, the results also imply that related neural processes may underlie visual awareness and the organization of voluntary behavior contingent on sensory cues.     

The role of attention and study time in explicit and implicit memory for unfamiliar visual stimuli

The bioavailability of lycopene from tomato juice and 2 dietary supplements, each containing 70-75 mg lycopene, was studied in 15 healthy volunteers in a randomized, crossover design. Subjects ingested lycopene-rich tomato juice, tomato oleoresin, lycopene beadlets, and a placebo for 4 wk each while consuming self-selected diets. Treatment periods were separated by 6-wk washout periods. Plasma lycopene concentrations, assessed at baseline and weekly throughout the treatment periods, were significantly higher during tomato juice, oleoresin, and lycopene beadlet ingestion than during placebo ingestion. Mean (+/-SEM) increases in plasma lycopene at week 4 of tomato juice, oleoresin, and lycopene beadlet ingestion were not significantly different: 0.24 +/- 0.07, 0.23 +/- 0.05, and 0.24 +/- 0.06 micromol/L, respectively. Plasma concentrations of phytofluene and phytoene, which were present in small amounts in tomato juice, oleoresin, and lycopene beadlets, increased significantly with ingestion of these 3 products. Beta-carotene, zeta-carotene, and 2,6-cyclolycopene-1,5-diol (a metabolite of lycopene)--also present in tomato juice and supplements--were significantly increased with consumption of the tomato juice and lycopene beadlets, but not with oleoresin consumption. A marked increase in plasma concentrations of an unknown compound was observed; it was detected in trace amounts in tomato juice, oleoresin, and lycopene beadlets, and had a maximum absorbance at 448 nm and a molecular weight of 556. Concentrations of plasma lycopene and other carotenoids with potential for enhancing human health can be increased by ingestion of realistic amounts of tomato juice. Lycopene appears to be equally bioavailable from tomato juice and the supplements used in this study.     

Age differences in the effects of conscious and unconscious thought in decision making.

The roles of unconscious and conscious thought in decision making were investigated to examine both (a) boundary conditions associated with the efficacy of each type of thought and (b) age differences in intuitive versus deliberative thought. Participants were presented with 2 decision tasks, one requiring active deliberation and the other intuitive processing. Young and older adults then engaged in conscious or unconscious thought processing before making a decision. A manipulation check revealed that young adults were more accurate in their representations of the decision material than older adults, which accounted for much of the age-related variation in performance when the full sample was considered. When only accurate participants were considered, decision making was best when there was congruence between the nature of the information and the thought condition. Thus, unconscious thought was more appropriate when participants relied on intuitive rather than deliberative processing to make their decision, whereas the converse was true with conscious thought. Although older adults displayed somewhat less efficient deliberative processing, their ability to process information at the intuitive level was relatively preserved. Additionally, both young and older adults displayed choice-supportive memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The locus of interference in the perception of simultaneous stimuli.

In 3 experiments with 48 college students (18–33 yrs old), performance on well-practiced target detection tasks, both auditory and visual, was little influenced by the number of simultaneous nontargets, but suffered if simultaneous targets were detected separately. It is suggested that only targets need pass through a limited-capacity system leading to awareness (and hence availability for report); nontargets can be identified and rejected by earlier parallel, unconscious processes. Since nontarget words can be rejected on the basis of meaning, stimuli must be fully identified before the limited-capacity system. More generally, performance decrements due to divided attention are usually marked whenever simultaneous stimuli (psychophysical, verbal) must be identified separately and independently; under these circumstances all stimuli must pass through the limited-capacity system to awareness. (74 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of inattention and hyperactivity/impulsivity in the positive illusory bias.

The present study examined the relationships among gender, inattention, hyperactivity/impulsivity, depressive symptoms, and biases in perceptions of scholastic competence in children. Participants were 38 children with predominantly inattentive symptoms (IA), 59 children with predominantly hyperactive/impulsive symptoms or a combination of hyperactivity/impulsivity and inattention (HICB), and 83 control (CTL) children. HICB children overestimated their scholastic competence more than IA children when reading and math achievement scores were used as criteria and more than CTL children when math achievement and teacher perceptions of children's competence were used as criteria. IA children generally did not differ from CTL children with regard to estimations of competence. Regression analyses suggested that positive illusory self- perceptions are associated with more severe hyperactivity/impulsivity, but not more severe inattention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The generality of accuracy and response sets in interpersonal perception.

In experiment I, 15 measures of Ss' perception of other people were obtained. Only 8 of the intercorrelations were significant. In experiment II, Ss' judgments of other people were obtained in 3 sessions distributed over a school year. Comparison of the 3 sets of judgments indicated low relationship among accuracy scores, high relationship among response-set scores. Assumption of general ability of interpersonal perceptiveness is untenable; reliability of interpersonal perception may be due to consistency in response set rather than in ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Decision rules in the perception and categorization of multidimensional stimuli.

This article examines decision processes in the perception and categorization of stimuli constructed from one or more components. First, a general perceptual theory is used to formally characterize large classes of existing decision models according to the type of decision boundary they predict in a multidimensional perceptual space. A new experimental paradigm is developed that makes it possible to accurately estimate a subject's decision boundary in a categorization task. Three experiments using this paradigm are reported. Three conclusions stand out: (a) Subjects adopted deterministic decision rules, that is, for a given location in the perceptual space, most subjects always gave the same response; (b) subjects used decision rules that were nearly optimal; and (c) the only constraint on the type of decision bound that subjects used was the amount of cognitive capacity it required to implement. Subjects were not constrained to make independent decisions on each component or to attend to the distance to each prototype. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of cognitive stimulation on the relations between age and cognitive functioning.

To make a convincing argument that cognitive stimulation moderates age trends in cognition there must be (a) a negative relation between age and level of cognitive stimulation, (b) a positive relation between level of cognitive stimulation and level of cognitive functioning, and (c) evidence of an interaction between age and cognitive stimulation in the prediction of cognitive functioning. These conditions were investigated in a study in which 204 adults between 20 and 91 years of age completed an activity inventory and performed a variety of cognitive tasks. Only the 1st condition received empirical support, and, thus, the results of this study provide little evidence for the hypothesis that cognitive stimulation preserves or enhances cognitive functioning that would otherwise decline. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The generality of cognitive complexity in the perception of people and inkblots.

2 experimental hypotheses were tested: (1) Significant positive relationships exist between the complexity of S's perceptions of people and the complexity of their perceptions of inkblots relative to the determinants used; and (2) Significant positive relationships exist between the complexity of S's perceptions of people and their perceptions of inkblots relative to the context elicited. A measure of cognitive complexity was derived from a concept-formation sorting task originally devised by Kelly. A modified Rorschach technique was used to measure cognitive complexity in the non-personal stimulus realm. Ss consisted of 40 college males. Significant relationships in the predicted direction were found for both hypotheses. Of the various Rorschach determinant categories, only M correlated significantly with the measure of complexity of perceptions of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Superior colliculus and active navigation: role of visual and non-visual cues in controlling cellular representations of space

To begin investigation of the contribution of the superior colliculus to unrestrained navigation, the nature of behavioral representation by individual neurons was identified as rats performed a spatial memory task. Similar to what has been observed for hippocampus, many superior collicular cells showed elevated firing as animals traversed particular locations on the maze, and also during directional movement. However, when compared to hippocampal place fields, superior collicular location fields were found to be more broad and did not exhibit mnemonic properties. Organism-centered spatial coding was illustrated by other neurons that discharged preferentially during right or left turns made by the animal on the maze, or after lateralized sensory presentation of somatosensory, visual, or auditory stimuli. Nonspatial movement-related neurons increased or decreased firing when animals engaged in specific behaviors on the maze regardless of location or direction of movement. Manipulations of the visual environment showed that many, but not all, spatial cells were dependent on visual information. The majority of movement-related cells, however, did not require visual information to establish or maintain the correlates. Several superior collicular cells fired in response to multiple maze behaviors; in some of these cases a dissociation of visual sensitivity to one component of the behavioral correlate, but not the other, could be achieved for a single cell. This suggests that multiple modalities influence the activity of single neurons in superior colliculus of behaving rats. Similarly, several sensory-related cells showed dramatic increases in firing rate during the presentation of multisensory stimuli compared to the unimodal stimuli. These data reveal for the first time how previous findings of sensory/motor representation by the superior colliculus of restrained/anesthetized animals might be manifested in freely behaving rats performing a navigational task. Furthermore, the findings of both visually dependent and visually independent spatial coding suggest that superior colliculus may be involved in sending visual information for establishing spatial representations in efferent structures and for directing spatially-guided movements.     

The what and the where of the pigeon's processing of complex visual stimuli.

Eight pigeons were trained on a go-no go visual discrimination involving I S+ and 15 S–s. The 16 discriminative stimuli were black-and-white line drawings created by the factorial combination of 4 different geometric shapes (wedge, cylinder, cone, handle) in 4 different spatial locations (right, left, above, below) in relation to a common shape (cube). All of the pigeons readily learned this complex visual discrimination. Each bird's pecking behavior was controlled by both attributes of the line drawings, but somewhat stronger stimulus control was exerted by the location of the added component than by its shape. Across all 8 pigeons, there was an inverse relation between stimulus control by component shape and component location. These results document pigeons' joint processing of "what" and "where" information in visual discrimination learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An investigation of tactile and visual stimuli in the roadway environment

Two critiques of D. J. Bem's (1996) "Exotic Becomes Erotic" (EBE) theory of sexual orientation are presented. First, the core proposition of EBE theory is considered; that is, the idea that adults are erotically attracted to the gender-based class of peers (males or females) who were dissimilar or unfamiliar to them in childhood. Studies cited by Bem and additional research show that EBE theory is not supported by scientific evidence. Second, Bem's claim that his theory applies equally to both sexes is questioned; instead the argument that it neglects and misrepresents women's experiences is made. Bem's conceptualization of erotic desire and his analysis of gender nonconformity illustrate this problem. It is suggested that different theories may be needed to explain the development of men's and women's sexual orientation.