The present study examined the effects of modality and location expectancy on reaction times. Participants judged the azimuth (left or right) for a sequence of auditory and visual targets. In experiment A, the majority (75%) of the targets were presented in an expected modality and location. In experiment B, the majority of the targets were presented in an expected modality and at an unpredictable location. In experiment C, the majority of the targets were presented in an expected location and the modality of the target was unpredictable. The reaction times for the targets under these conditions were faster than when the targets were unexpected or without any expectancy. The results demonstrate that the costs and benefits in experiment A (two-target information) were larger than those in either experiment B or C. Moreover, the costs and benefits in experiment A were almost equal to the total of the costs and benefits in experiments B and C. The results also suggest that spatial attention and modality attention are separable and additive.
The within-session decrease in the speed of operant responding by rats was investigated for every reinforcement which was delivered. Eighteen rats in the continuous reinforcement (CRF) group responded to the CRF schedule until 121 reinforcements were obtained in each session. Eighteen rats in a variable interval (VI) group responded to a VI 15-second schedule until 101 reinforcements were obtained in each session. A clock-dependent VI schedule (Snapper, Shimoff, & Schoenfeld, 1971) was used to steadily provide reinforcements, regardless of any change in the response rate. The data from the last 12 of 15 sessions were analyzed. The inter-reinforcement time was observed to increase within CRF sessions. In contrast, the inter-reinforcement time remained at approximately 15 seconds within VI sessions. In both of the groups the response speed (the number of responses per second) was well described as a linear function of the number of reinforcements obtained. The response speed therefore decreased in proportion to the increase in the number of reinforcers within the sessions.
The Rey-Osterrieth Complex Figure Test (ROCF) is a widely used neuropsychological test for the evaluation of visuospatial abilities and visual memory. Traditional administration of the ROCF uses an incidental procedure in which participants are not informed that there would be recall test in copy trial. In the case of language stimuli, it is known that intentional learning in which the preceding notice of the subsequent reproduction test improves the reproduction results, might be generated. However, the effects on nonverbal visual stimuli have been scarcely examined. The aim of this study is to determine whether there would be intentional learning effects in the recall of the ROCF. The ROCF was administered to three groups with 20 healthy students in each condition; incidental learning, intentional learning, and confirmation instruction. The results indicated the scores of three groups were not significantly different on copy trial and recall test. The relevance of these findings to the relationship with coding of nonverbal visual stimuli was discussed.
Visual search performance can be facilitated implicitly through repetitive viewing of the same layout of a search display (the contextual cueing effect). Researchers know that selective attention affects the occurrence of the cueing effect, but it has not been clear whether divided attention has the same effect. By introducing an attentional blink procedure, this study tested whether implicit learning of visual displays occurs while attention is devoted to a primary task. Observers searched for two digits among distracter letters. In the training phase, the sequence of rapidly presented distracters was predictive of the location of the second target; an attentional blink effect was obtained. More importantly, when the predictive value was removed in the testing phase, search performance slowed. These results suggest that the visual system can acquire spatiotemporal contextual memory even when deprived of attentional resources.
While various robots have been developed so far, human is even more dexterous than current robots. However, if we focus on speed or acceleration, robots have more than human. Current robot technologies enabled us to develop a high speed vision system with the processing speed of 1,000 frames/sec, while just catching 30 frames/sec seems to be far beyond human capability. In addition to this, an actuator whose acceleration is 20 times more than that of human, has been developed. In this report, we explore how the above technologies will open a new world in the future.
Our temporal perception can be lengthened or shortened by several factors. For example, the perceived duration of presented stimuli is lengthened by increasing the quantity of stimulus. In contrast, perceived duration is shortened as difficulty of concurrently imposed tasks increases. Previous studies have mainly examined factors that are consciously perceivable, and have found that they produce robust effects on the temporal perception. However, it has not been examined whether perceived duration is influenced by unconscious process, such as implicit memory. Here we review the studies investigating that time perception is affected by implicit/explicit memory, and discuss the effect of conscious/unconscious process on time perception.
Seven experiments investigating the distortion in time perception during seeing motion patterns are reviewed. The first and second experiments showed the fundamental results in which duration estimates increase with motion velocity but duration estimates in the stationary condition are greater than those of the slowest velocity condition. The former is called as the velocity effect on time perception. The next experiment showed that the velocity effect remains even if observers focus on the other stimulus superimposed with motion pattern. Other experiments showed that the velocity effect can be the temporal-frequency effect and occur in the portion of stimulus onset and offset and that the temporal-frequency effect is also observed in the auditory modality. The last two experiments examined a relationship between the velocity effect and the asynchronous phenomenon of color and motion and showed that different processes are involved in these effect and phenomenon. These results indicate that multiple processes intricately concern the distortion in time perception.
Studies on animal timing have developed nonverbal experimental procedures and have shown that animal participants in research can learn to time intervals of arbitrary duration. Under immediate timing procedures, such as a fixed-interval schedule and a peak procedure, animals wait a fixed proportion of an interval before starting to respond. Under a retrospective timing procedure, animals can discriminate between a short and a long interval; the bisection point is approximately at the geometric mean of the two intervals. Furthermore, behavioral measures of timing in both kinds of the procedures have a scalar property, which indicates that animal timing conforms to Weber's law. Theories of animal timing have successfully explained these phenomena. However, issues, such as credit-assignment problems, animals' temporal tracking, and animals' "episodic-like" memory, remain and call for further empirical and theoretical exploration.
In the present article, the interface between social psychology and clinical psychology was discussed by illustrating the relationship between self-focused attention and depression. At first, the three-phase model of self-focus and depression (Sakamoto, 2000) was presented to explain the mechanism of the onset and maintenance of depression. In this model, the relationship between self-focus and the course of depression was divided into three phases: (1) initiation, (2) operation, and (3) maintenance. Next, the merit and methodological problems in social psychological studies of depression (i.e., analogue studies) were discussed. Finally, future tasks in encouraging the interface between social psychology and clinical psychology (especially, cognitive-behavioral therapy) in Japan were discussed.
In this article, we present our neuroimaging studies by functional Magnetic Resonance Imaging (fMRI) about the brain mechanism of cognition toward elucidation of pathophysiology in depression. The first and second data show the brain mechanism (Kurosaki et al., 2005; Ueda et al., 2003) related to dysfunctional beliefs and systematic cognitive errors identified by Beck (1967), and the third is that (Tanaka et al., 2004) related to differential activation hypothesis proposed by Teasdale (1988). Lastly, we also show the change of brain function before and after cognitive behavioral group therapy (CBGT). Depressed patients before the CBGT showed attenuated activation in the dorsolateral prefrontal cortex, parietal cortex, and striatum were activated during the task. After the CBGT, the brain activation in good responders was restored as same as that in healthy control. However, in poor responder, there was no change on brain activation between before and after CBGT.
Numerous epidemiological studies in psychiatry demonstrate that an early adversity is a major risk factor for depression in adulthood. Several rodent studies reveal that neonatal isolation, maternal separation, and low maternal care induce the hyperactivation of the hypothalamo-pituitary-adrenal (HPA) axis in response to restraint stress in adulthood. Since the activation of the HPA axis plays an important role in the pathophysiology of depression, it is conceivable that the enhanced response of the HPA axis to adulthood stress induced by early adversities may be involved in the increased susceptibility to depression. We examined the influence of neonatal isolation (NI) on the susceptibility to learned helplessness (LH),an animal model of depression, in adult rats. In addition, we examined the difference of gene expression profiles in the hippocampus between the NI+LH and non-NI+non-LH rats to elucidate the molecular mechanism for the enhanced susceptibility to depression induced by an early adversity. Behavioral analysis showed that the prevalence of LH in the rats subjected to NI was significantly higher than that in the rats without NI. Molecular analysis indicated that the significant decrease in the hippocampal level of LIMK-1 was associated with the increased susceptibility to depression found in the rats subjected to NI. These findings suggest that the deceased expression of LIMK-1 may induce the morphological and functional change in the hippocampus, and subsequently increase the susceptibility to depression in response to adulthood stress.
Music therapy is relatively a new treatment area in Japan. It has been practiced in hospitals, institutions for elderly people and/or disabled population. The definition of the Japanese Music Therapy Association is the following: Music therapy is to use music purposefully with plans to recover from mental and physical disability, to maintain our functions, to raise our QOL, and to make changes in actions by physiological psychological social aspects in music. Music therapists use pre-composed music and improvisation according to clients' situations and needs. There are various elements and forms in music, and we music therapists have to use it clinically according to clients' needs and their treatment plan. Here we experience these musical elements and forms and witness how music motivate clients and release actions and expressions. We review some psychological ideas which is essential to practicing music therapy and analyze real sessions to see how clinical music influence clients psychologically and socially.
Human body is a special object to be perceived for us. We reviewed articles on relationship between human body and perception or embodied perception as well as those on recognition of human face and body. In this vein, we summarized our studies on perception and recognition of human body postures and movements, its developmental experiments using infants, and multimodal encoding/recognition of body postures. It is proposed that our perception/recognition of human body is determined by 'biomechanical constraints'.
Visual acuity tests are implemented to detect functional amblyopia (lazy eye) and other diseases in the national health examination for children of three years of age. Children who can accurately identify symbols corresponding to a visual acuity rate of 0.5 with both their left and right eyes are judged to have passed the test. This standard was adopted with due consideration for the average visual acuity of children aged three years and zero months and adopted as a benchmark in order to check for the presence of abnormalities requiring treatment such as functional amblyopia among this age group. It was found that children who passed the visual acuity test had no signs of ophthalmologic disease requiring early therapeutic intervention. In contrast, children who failed to pass the visual acuity test occasionally suffered ophthalmologic disease requiring immediate treatment. Accordingly, the standard adopted was regarded as reasonable. The test utilizes Landolt ring charts or picture optotypes, the former of which are characterized by remarkable precision. The latter, meanwhile, are characterized by excellent availability as a rating tool. This screening method has contributed to promotion of early detection and treatment of functional amblyopia. As a result, the majority of children diagnosed with amblyopia are able to acquire the normal visual acuity before entering elementary school.
It has been proposed that objects which appear to be expanding, and represent approaching objects, are easier to detect than objects which appear to be contracting (Takeuchi, 1997; Shirai & Yamaguchi, 2004). To investigate this asymmetry in a visual search task we examined the detection of approaching and receding objects which were defined by moving cast shadows. The results showed that an "approaching" target among "receding" distractors was detected faster and more accurately than a "receding" target among "approaching" distractors (Experiment 1). In addition, this asymmetry did not occur if the luminance of the shadows was lighter than the background (Experiments 2 and 3. These findings suggest that the asymmetry of the perception of motion-in-depth could be caused by the depth information of cast shadows.
After a prolonged viewing of stimuli moving in one direction subsequent static stimuli appear to move in the opposite direction (the motion aftereffect; MAE). It is known that MAEs with achromatic luminance stimuli are enhanced when static reference stimuli are displayed. In this study we examined the effect of static reference on MAEs with isoluminant chromatic stimuli. The results were consistent with other studies and robust MAEs were observed when the adaptors and tests were modulated along a different color axis. Furthermore, the static MAE was increased by the reference only when the adaptor and/or test were achromatic. In contrast, the reference did not have an effect on the MAE with a dynamic test. The results revealed that luminance and chromatic signals are processed independently in an early stage, and share common motion mechanisms later in higher stages.
In a time-to-passage (TTP) paradigm the observers were asked to estimate the time for a moving target to pass through a pre-determined landmark. A circular target smoothly moved in a linear path and was gradually occluded by a static rectangular screen. Additionally, a luminance border parallel to the motion path was presented as a pictorial cue indicating a ground surface. Since the motion path was oblique (+45 or - 45 degrees) or horizontal, the target appeared as if it descended, ascended, or translated on the ground. As a result, when the target always contacted the solid line the TTP was significantly shorter while descending than while ascending. On the other hand, when the target was slightly away from the border, no significant effect of the slope of the motion path on the TTP was obtained. The results indicated that different motion impressions caused by naive physics affected the TTP judgments.
When two identical visual objects move across each other in a two-dimensional display, there is a perception of streaming through, or bouncing off each other, at the position of their coincidence. In our preliminary observation, a switch of object features such as color between the two objects, biased the perception towards bouncing. We have examined the characteristics of spatiotemporal integration of object features in the stream/bounce event. By changing the duration of the object presentation after a color switch at their coincidence we explored the spatiotemporal properties of object color to substantially affect the stream or bounce event. The results revealed that 100 ms after the color switch, the observers can utilize the color change information to determine the stream/bounce event. Additionally, the percentage of bouncing percepts reached a maximum rate 150 ms after the color switch. A follow-up experiment showed that the results were not affected by the speed of the objects. This result sugges ed that the post-coincidence duration is crucial for spatiotemporal integration of the object color feature in event perception.
We report the development of cortical responses (steady-state visual evoked potentials: VEPs) to radial expansion/contraction. Forty-four 3-4-month-olds and 9 adults viewed moving dots which cyclically (2.085 Hz) alternated between radial expansion (or contraction) and random directional motion. The first harmonic (F1) response in the VEPs must arise from global-motion- sensitive mechanisms. The results indicated that the F1 amplitudes for contraction were significantly larger than those for expansion for the 4-month-olds and the adults but not for the 3-month-olds. These results suggest that the human cortical motion mechanisms have an asymmetrical sensitivity for radial expansion/contraction which develops at around 3 to 4 months of age.
Ono and Kawahara (2006) have reported that when the apparent size of a visual object in the Ebbinghaus illusion was overestimated its perceived duration was longer than when its size was underestimated. Because the time estimation task and the size estimation task were presented consecutively in their study, the participants might have estimated the area size during the time estimation task. In the present study the time estimation and size estimation tasks were conducted in separate blocks. This procedure was used to determine whether the effect of apparent visual size on the perceived duration was because the subjective area size was altered by the illusion, or whether it was an artefact caused by the participants engaging in the size estimation task. The results indicated that the perceived duration of apparently large stimuli was longer than that of apparently small stimuli, even if the participants were not engaged in the size estimation task, and revealed that time perception is influenced by subjective area size.
Two monolingual lexical decision tasks and a cued language-switching task were used to explore the cognitive processing of two-Chinese-character compound words in proficient Chinese-Japanese bilinguals. The results showed one-way facilitation and inhibition from L1 to L2 when bilinguals performed lexical decision tasks in both languages, respectively. Interactive interference and facilitation were observed in when sporadic language-switching is required.
Two experiments investigated the visual processing of hierarchical stimuli by chimpanzees. Using a delayed matching-to-sample (DMTS) task, five chimpanzees were tested for their perceptual dominance of global or local information in hierarchically designed figures which consisted of global configurations and local elements. The results of the first experiment displayed individual differences in global-local processing of the figures. Two of the chimpanzees exhibited a advantage for local level processing and the others exhibited an advantage for processing global shape. The results of the second experiment revealed that manipulation of the density of local elements affected the performance of the three chimpanzees who had global precedence but did not affect the performance of the other two chimpanzees who had local precedence. These results suggest that a precedence for global or local visual processing in chimpanzees is not determined a priori but depends on strategies which are learned individually to solve a given task.
We investigated object-based attention in chimpanzees with an attention shift task. The chimpanzees were rewarded by touching a target (a red disk) which appeared after a brief presentation of a cue (a yeHow square). We hypothesized that if object-based attention does work, the reaction time (RT) would be shorter when the target appeared in the cued rectangle than in the other rectangle. We could not observe any evidence of such a within-object benefit in Experiment 1, in which two rectangles were arranged in parallel. In Experiment 2, the rectangles were arranged horizontally in a line, to reduce variation in the distance from the start key to each target location. The RT pattern of the chimpanzees in Experiment 2 suggested an object-based attention in them.
Contingent attentional capture occurs when a stimulus property captures an observer's attention, usually related to the observer's top-down attentional set for target-defining properties. This study examined whether contingent attentional capture occurs for a stimulus property that does not define the target by itself, but is congruent with the target-defining property. In an RSVP stream, we defined the target by a color (e.g., a green-colored Japanese Kanji character). Before the target onset we presented a distractor that referred to the target-defining color (e.g., a white-colored Kanji character with the meaning "green"). We observed that the distractor produced contingent attentional capture which was revealed by a deficit in identifying the subsequent target. This result suggested that the attentional set included congruency between the activated meaning and the target-defining color to detect the target.