Aging and tactile temporal order

Although it is generally held that speed of processing declines with age, there have been few studies in which tactile temporal processing has been examined with older subjects. In the present study, temporal order judgments were obtained from a group of younger subjects (n = 28, mean age = 23.5 years) and a group of older subjects (n = 93, mean age = 69.8 years). The subjects judged the temporal order of two patterns presented to the same finger, four patterns presented to the same finger, and two patterns presented to different hands. Depending on the task, the average thresholds for the older subjects ranged from two to five times longer than the thresholds from the younger subjects. In absolute terms, the largest difference between the young and older subjects was seen in correctly identifying the order of four patterns, a difference of more than 500 msec. There was some support for the decline in temporal processing being due in part to a slowing in cognitive processing, and, depending on the task, in part to stimulus persistence and difficulty in pattern identification.     

Temporal order and processing acuity of visual,auditory, and tactile perception in developmentally dyslexic young adults

We studied the temporal acuity of 16 developmentally dyslexic young adults in three perceptual modalities. The control group consisted of 16 age- and IQ-matched normal readers. Two methods were used. In the temporal order judgment (TOJ) method, the stimuli were spatially separate fingertip indentations in the tactile system, tone bursts of different pitches in audition, and light flashes in vision. Participants indicated which one of two stimuli appeared first. To test temporal processing acuity (TPA), the same 8-msec nonspeech stimuli were presented as two parallel sequences of three stimulus pulses. Participants indicated, without order judgments, whether the pulses of the two sequences were simultaneous or nonsimultaneous. The dyslexic readers were somewhat inferior to the normal readers in all six temporal acuity tasks on average. Thus, our results agreed with the existence of a pansensory temporal processing deficit associated with dyslexia in a language with shallow orthography (Finnish) and in well-educated adults. The dyslexic and normal readers' temporal acuities overlapped so much, however, that acuity deficits alone would not allow dyslexia diagnoses. It was irrelevant whether or not the acuity task required order judgments. The groups did not differ in the nontemporal aspects of our experiments. Correlations between temporal acuity and reading-related tasks suggested that temporal acuity is associated with phonological awareness.     

Identification of scanned and static tactile patterns

Most of the studies in which the interactions between target and nontarget spatial patterns have been examined have tested patterns that are generated statically. Static patterns are those in which all the elements of the pattern are presented at the same time and at a fixed location on the skin; however, most tactile information comes to the skin by means of patterns' being scanned across the surface of the skin. In the present study, the interactions between target and nontarget patterns were measured for patterns generated in both the static and the scanned modes. Nontarget patterns often interfere with the perception of target patterns. Using patterns generated in the static mode, previous studies have identified two factors that produce interference in pattern identification: response competition and masking. Masking, in turn, appears to be the result of temporal integration of the target and nontarget patterns, as well as the displacement of target features. In the present study, these factors were examined for patterns generated in both static and scanned modes. Regardless of the mode in which the patterns were generated, similar functions were obtained relating identification performance to the temporal separation between the target and the nontarget patterns. Although statically generated patterns are more easily identified than scanned patterns, particularly at brief durations, mechanisms such as response competition, temporal integration, and the displacement of target features appear to be factors that affect scanned patterns to nearly the same degree as static patterns.     

Temporal resolution of the aging tactile sensory system

Oral and nonoral tactile fusion thresholds were obtained for 39 subjects ranging in age from 12 to 76 yr. Regression analysis of the data indicated a trend for fusion thresholds to become poorer with age. Further statistical testing indicated mean threshold and variability differences between subjects when they were placed into four groups according to age.     

Temporal and intensitive factors in comparative judgments of tactile space.

Temporal imbalances between the successive stimulation of pairs of loci on each forearm altered judgments of the equality of the spatial extents between sets of loci. The spatial judgments became increasingly inaccurate as the temporal imbalance was increased, i.e., the Tau effect. Changes in stimulus intensity also influenced the dependency of spatial judgments on temporal factors. The data suggest that concomitant variations of spatial, temporal, and intensitive components of a vibrotactile stimulus "package" can produce systematic perceptual effects of potential significance in the design of vibrotactile sensory substitution systems.     

Temporal order judgments with amnesia

The hypothesis that patients with anterograde amnesia fail to recognize the temporal relations among recognizable past events was evaluated. Experiment 1 showed that order recognition for words in a list was at chance levels even though event recognition was significantly above chance. The same pattern did not obtain for intact adults. Experiment 2 examined event and order recognition for news events. Amnesics' event recognition for news events was quite accurate and comparable to controls, yet their order recognition was significantly below that of controls, again at chance levels. It is argued that the failure to encode the temporal relations among events has broad consequences for memory performance in general.     

Temporal order judgment in dyslexia

Hari et al. (Brain 174:1373-1380, 2001) demonstrated that dyslexics showed a sluggish attention capture in both visual hemifields. Additionally, they indicated a left-right asymmetry in the perception of temporal order of two visual stimuli (they performed worse than controls only if the stimulus in the left hemifield preceded that in right hemifield). They suggested that a left-sided minineglect is associated with dyslexia. We hypothesized that if a kind of neglect syndrome is responsible for the asymmetry they found, dyslexics should not only show a left-right asymmetry in temporal order judgment of two laterally presented stimuli but also perform equally well as controls when the stimuli are vertically aligned. Our results indicated that in both tasks dyslexics performed generally worse than normal readers. The results suggest that dyslexics suffer from a more general problem of order discrimination.     

The effect of motion on tactile and visual temporal order judgments

Four experiments were conducted, three with tactile stimuli and one with visual stimuli, in which subjects made temporal order judgments (TOJs). The tactile stimuli were patterns that moved laterally across the fingerpads. The subject's task was to judge which finger received the pattern first. Even though the movement was irrelevant to the task, the subjects' TOJs were greatly affected by the direction of movement of the patterns. Accuracy in judging temporal order was enhanced when the patterns moved in a direction that was consistent with the temporal order of presentation--for example, when the movement on each fingerpad was from right to left and the temporally leading site of stimulation was to the right of the temporally trailing site of stimulation. When movement was inconsistent with the temporal order of presentation, accuracy was considerably reduced, often well below chance.The bias in TOJs was unaffected by training or by presenting the stimuli to fingers on opposite hands. In a fourth experiment, subjects judged the temporal order of visual stimuli that, like the tactile stimuli, moved in a direction that was either consistent or inconsistent with the TOJ. The results were similar to those obtained with tactile stimuli. It is suggested that the bias may be affected by attentional mechanisms and by apparent motion generated between the two sites on the skin.     

Temporal order relations in language comprehension

The role of temporal orientation (chronological or reverse) and chronological distance (close, intermediate, or distant) in general event knowledge on language comprehension was examined. Experiment 1 used a relation-recognition paradigm in which the comprehension of a target event could be facilitated or disrupted by the temporal orientation implied by the prior information. Experiments 2 and 3 used a sentence-probe-recognition paradigm in which the temporal orientation, the stimulus onset asynchrony, and the chronological distance between the sentence event and the probe event were manipulated. The results demonstrated that readers used temporal information conveyed by their knowledge to construct situation models while comprehending sentences. The internal temporal dimension appeared to be directional and reflected the chronological distance between everyday events.     

幼儿心理理论与时序记忆的关系——来自时序记忆分离的证据

研究检验了时序记忆与心理理论的关系.实验一对39个3.5～5.5岁儿童的时序记忆能力以及心理理论表现进行测查,考察了因果关系、相关关系、无因果无相关关系三类不同性质的材料测得的时序记忆与心理理论的关系;90个儿童参与了实验二,通过正叙、倒叙、预叙三种叙述方式将时序记忆分离为理解性时序记忆和机械性时序记忆,再分别考察与心理理论的关系.结果发现,在不同性质的实验材料中,时序记忆与心理理论相关均不显著;5.5岁儿童的理解性时序记忆显著高于3.5岁儿童,4.5岁、5.5岁儿童的机械性时序记忆显著高于3.5岁儿童;只有理解性时序记忆能够预测儿童的心理理论成绩.     

Temporal integration of vibrotactile patterns

Three experiments were conducted to measure the temporal integration of vibrotactile patterns presented to the fingertip. In Experiment 1, letters were divided in half and the time between the onsets of the first half of the letter and second half of the letter, stimulus onset asynchrony (SOA), was varied. The recognizability of the letters declined as the SOA was increased from 9 to 100 msec. In Experiment 2, the time between two patterns constituting a masking stimulus was varied and the stimulus effectiveness in interfering with letter recognition was determined. The amount of masking increased as the SOA increased from 9 to 50 msec. In Experiment 3, the SOA between a letter and its complement (the portions of the tactile array not activated by the letter) was varied. Increasing SOA from 9 to approximately 50 msec led to increasingly accurate letter recognition. The results of the three experiments suggest that the skin is capable of complete temporal integration over a time period of less than 10 msec, and that the temporal integration function becomes asymptotic in 50 to 100 msec. The results also suggest that the onset of a vibrotactile pattern is critical for generating contours. The implications of the results for modes of generating tactile patterns and for temporal masking functions are discussed.     

Infant patterns of reactivity to tactile stimulation during parent-child interaction

Touch is the primary modality infants use to engage with the world; atypical responses to tactile stimuli may indicate risk for disordered outcomes. The current study examined infants’ responses to tactile stimulation within parent-child interaction, adding to prior knowledge based on parent report. Nine-month-old infants (N = 497) were observed while parents painted and pressed infants’ hands and feet to paper to make designs. Positive and negative affect and gazing away, exploring, and resistance behaviors were coded. Latent Class Analysis of observed behaviors yielded four tactile response patterns partially consistent with current nosology for sensory processing patterns: Low Reactive, Sensory Overreactive, Sensory Seeking, and Mixed Over/Underreactive. To evaluate whether patterns made valid distinctions among infants, latent classes were examined in relation to parent-reported temperament. Infants in the Mixed Over/Underreactive class were rated higher in distress to limitations and activity level than other infants. Sensory processing patterns observed in parent-child interaction are consistent with those identified by parent-report and may be used in future research to elucidate relations with temperament and typical and atypical development.     

Temporal order of strokes primes letter recognition

Does the perception of objects that are the result of human actions reflect the underlying temporal structure of the actions that gave rise to them? We tested whether the temporal order of letter strokes influences letter recognition. In three experiments, participants were asked to identify letters that temporally unfolded as an additive sequence of letter strokes, either consistent or inconsistent with common writing action. Participants were significantly faster to identify letters from consistent temporal sequences, indicating that the initial part of the sequence contained sufficient information to prime letter recognition. We suggest that letter perception reflects the temporal structure of letter production; in other words, Simon sees as Simon does.     

Temporal order of strokes primes letter recognition

Does the perception of objects that are the result of human actions reflect the underlying temporal structure of the actions that gave rise to them? We tested whether the temporal order of letter strokes influences letter recognition. In three experiments, participants were asked to identify letters that temporally unfolded as an additive sequence of letter strokes, either consistent or inconsistent with common writing action. Participants were significantly faster to identify letters from consistent temporal sequences, indicating that the initial part of the sequence contained sufficient information to prime letter recognition. We suggest that letter perception reflects the temporal structure of letter production; in other words, Simon sees as Simon does.     

Processing of sequential tactile patterns: effects of a neutral stimulus

The perception of a target pattern may be interfered with by the presentation of a nontarget pattern in close temporal and spatial proximity with it. The results from previous studies suggested that much of this interference is the result not of masking but of response competition, subjects responding with the nontarget instead of the target. Using a 4-to-2 paradigm in which four target patterns are mapped onto two responses, it was shown that neutral patterns (i.e., patterns with no responses associated with them) produce considerable interference. The amount of interference is less than that produced by patterns associated with incorrect responses but greater than that produced by patterns associated with correct responses. The amount of interference produced by neutral patterns did not vary as a function of the form of the neutral pattern (Experiments 1 and 2); however, the amount of interference did depend on the degree and nature of the similarity between the neutral and target patterns (Experiments 3 and 4). The results indicate that recent studies have underestimated the amount of interference due to masking and overestimated the amount due to response competition. Response competition may either hinder or help target categorization depending on the nontarget pattern.     

Temporal order psychometric functions based on confidence-rating data

Psychophysical tasks involving confidence judgments allow the simultaneous generation of a family of psychometric functions. Sternberg, Knoll, and Mallows (1975) have demonstrated the power of the multiple-function approach in evaluating models concerned with specifying the source of errors in judgments of simultaneity and temporal order. In the present paper, data from a temporal order task requiring confidence ratings are examined, and a number of models for successiveness and order judgments evaluated.