Stimulus and response frequency and sequential effects in memory scanning reaction times.

1974 ◽  
Vol 102 (6) ◽  
pp. 1092-1099 ◽  
Author(s):  
John Theios ◽  
Dennis G. Walter
Keyword(s):  
Reaction Times ◽  
Memory Scanning ◽  
Sequential Effects ◽  
Response Frequency

scholarly journals The diffusion model of reaction time for recent negative probes

2020 ◽  
Vol 13 (1) ◽  
pp. 35-50
Author(s):  
B.B. Velichkovsky ◽  
F.R. Sultanova ◽  
D.V. Tatarinov ◽  
A.A. Kachina
Keyword(s):  
Diffusion Model ◽  
Drift Rate ◽  
Short Term Memory ◽  
Reaction Times ◽  
Long Term Memory ◽  
Memory Scanning ◽  
Short Term ◽  
Cognitive Representations ◽  
Term Memory ◽  
Scanning Task

The study investigates the problem of information displacement from short-term memory. In two experiments, reaction times for recent negative probes were analyzed in the Sternberg’s memory scanning task. The diffusion model of reaction times was used with parameters estimated with the fast-dm software. It was found (experiment 1) that recent negative probes are characterized by a reduction in the speed of information accumulation (drift rate). This suggests residual activation of irrelevant cognitive representation in memory after they have been displaced from short-term memory. It was also found (experiment 2) that negative probes semantically related to items in a preceding target set (semantic recent negative probes) are characterized by a similar decrease in the drift rate. This suggests activation spreading from irrelevant cognitive representations displaced from short-term memory along semantic connections and identifies activated long-term memory as the target of information displacement from short-term memory. Additional mechanisms of short-term memory scanning (negative priming and dynamic decision thresholds) are discussed.

scholarly journals The spatiotemporal link of temporal expectations: contextual temporal expectation is independent of spatial attention

2021 ◽  
Author(s):  
Noam Tal-Perry ◽  
Shlomit Yuval-Greenberg
Keyword(s):  
Spatial Attention ◽  
Hazard Rate ◽  
Receptive Fields ◽  
Reaction Times ◽  
Rate Function ◽  
Hazard Rate Function ◽  
Spatial Cues ◽  
Sequential Effects ◽  
Temporal Expectation ◽  
Temporal Structures

Temporal expectation is the ability to construct predictions regarding the timing of events, based on previously-experienced temporal regularities of different types. For example, cue-based expectations are constructed when a cue validly indicates when a target is expected to occur. However, in the absence of such cues, expectations can be constructed based on contextual temporal information, including the event's hazard-rate function - its moment-by-moment conditional probability that changes over time; and prior experiences, which provide probabilistic information regarding the event's predicted timing (sequential effects). It was previously suggested that cue-based temporal expectation is exerted via synchronization of spatially-specific neural activity at a target's predictable time, within receptive fields corresponding to the target's expected location. Here, we tested if the same theoretical model holds for contextual temporal effects. Participants (n = 40) performed a speeded spatial-cueing detection task, with two-thirds valid spatial cues. The target's hazard-rate function was modulated by varying the foreperiod - the interval between the spatial cue and the target - among trials, and was manipulated between groups by changing the interval distribution. Reaction times were analyzed using both frequentist and Bayesian generalized linear mixed models, accounting for hazard and sequential effects. Results showed that the effects of contextual temporal structures on reaction times were independent of spatial attention. This suggests that the spatiotemporal mechanisms, thought to account for cue-based expectation, cannot explain other sources of temporal expectations. We conclude that expectations based on contextual structures have different characteristics than cue-based temporal expectation, suggesting reliance on distinct neural mechanisms.

scholarly journals Flanker Task Performance in Isolated Dystonia (Blepharospasm): A Focus on Sequential Effects

2020 ◽  
Vol 10 (2) ◽  
pp. 76
Author(s):  
Max Pekrul ◽  
Caroline Seer ◽  
Florian Lange ◽  
Dirk Dressler ◽  
Bruno Kopp
Keyword(s):  
Hemifacial Spasm ◽  
Flanker Task ◽  
Reaction Times ◽  
Preceding Trial ◽  
Response Sequence ◽  
Motor Symptom ◽  
Group Differences ◽  
Control Group ◽  
Sequential Effects ◽  
Specific Finding

Isolated dystonia manifests with involuntary muscle hyperactivity, but the extent of cognitive impairment remains controversial. We examined the executive functions in blepharospasm while accounting for motor symptom-related distractions as a factor often limiting the interpretability of neuropsychological studies in dystonia. Our control group comprised of patients with hemifacial spasm, which is a condition producing similar motor symptoms without any central nervous system pathology. Nineteen patients with blepharospasm and 22 patients with hemifacial spasm completed a flanker task. Stimulus congruency on the current trial, on the preceding trial, and a response sequence served as independent variables. We analyzed the response time and accuracy. Gross overall group differences were not discernible. While congruency, congruency sequence, and response sequence exerted the expected effects, no group differences emerged with regard to these variables. A difference between patients with blepharospasm and those with hemifacial spasm consisted in longer reaction times when responses had to be repeated following stimulus incongruency on the preceding trial. We conclude that patients with blepharospasm seem to have difficulties in repeating their responses when incongruency on preceding trials interferes with habit formation or other forms of fast routes to action. Our specific finding may provide an opportunity to study altered basal ganglia plasticity in focal dystonia.

Interactions in the Discrimination and Absolute Judgement of Orientation and Length

Perception ◽  
1988 ◽  
Vol 17 (2) ◽  
pp. 177-189 ◽  
Author(s):  
Miri Dick ◽  
Shaul Hochstein
Keyword(s):  
Reaction Time ◽  
Sensory Processing ◽  
Discrimination Task ◽  
Reaction Times ◽  
Two Dimensions ◽  
Orientation Discrimination ◽  
Sequential Effects ◽  
Amount Of Information ◽  
Random Fashion ◽  
Absolute Judgement

An asymmetric model is described for interactions in the perception of two dimensions (length and orientation) of a single visual stimulus. Two methods were used to test these interactions, and models for the interpretation of the possible outcomes of these tests are discussed. A length discrimination task showed facilitation (decreased reaction time) when orientation was covaried with length, and interference (increased reaction time) when random orientation variation was introduced. A smaller effect was seen when length was varied in an orientation discrimination task in a correlated or random fashion. Analysis of sequential effects showed that reaction times are fastest on repetition trials and are slowed by either the need to change the response or the need for additional sensory processing. With the second method, it was found that the amount of information transmitted in the estimation of orientation was not affected by the introduction of the redundant dimension of length, but that there was a significant gain in the amount of information transmitted in the estimation of length by the addition of the redundant dimension of orientation. It is concluded that orientation is probably a perceptual primitive of the visual system whereas length is a computed variable.

scholarly journals Event boundaries are steppingstones for memory retrieval

2021 ◽  
Author(s):  
Sebastian Michelmann ◽  
Uri Hasson ◽  
Kenneth Norman
Keyword(s):  
Response Times ◽  
Level Structure ◽  
Reaction Times ◽  
Memory Search ◽  
Mental Simulation ◽  
Memory Scanning ◽  
Retrieval Process ◽  
Fine Grained ◽  
Actual Duration ◽  
High Level

Personal experience extends over time. When we recall memories from our lives, we often scan extended episodes to remember, for instance, where we placed our car keys. Here we investigate the hypothesis that high level structure, marked by boundaries between events, guides us through this retrieval process. We present a model of memory search in which humans can replay past experience on a fine-grained temporal scale, but also skip ahead to the beginning of a new event in order to speed up the retrieval process. In a naturalistic interview paradigm, we provide evidence in human response times for such a skipping mechanism: When participants scanned extended segments from a movie in their memory, their reaction times were better explained by a model incorporating the number of event boundaries in the segment and the distance of the target to the previous event boundary (with both predictors explaining significant variance), compared to a model incorporating the actual duration of a segment. This supports the idea that, in scanning their memory, humans can skip to the beginning of a new event if they decide that the target is not present in that event; this has the effect of decoupling their memory scanning reaction times from the actual duration of the segment. This conclusion is further supported by the results of a second study where participants were asked to do detailed mental simulation instead of memory scanning. Participants took substantially longer to perform such mental simulation compared to participants that scanned their memory. Those mental simulation times were still explained better by a model where participants skip, but -- compared to memory scanning -- the threshold for skipping was much higher.

scholarly journals Human inferences about sequences: A minimal transition probability model

2016 ◽  
Author(s):  
Florent Meyniel ◽  
Maxime Maheu ◽  
Stanislas Dehaene
Keyword(s):  
Transition Probabilities ◽  
Transition Probability ◽  
Probability Model ◽  
Reaction Times ◽  
Time Varying ◽  
Sequential Effects ◽  
The Core ◽  
Human Sequence ◽  
Transition Probability Model ◽  
The Brain

The brain constantly infers the causes of the inputs it receives and uses these inferences to generate statistical expectations about future observations. Experimental evidence for these expectations and their violations include explicit reports, sequential effects on reaction times, and mismatch or surprise signals recorded in electrophysiology and functional MRI. Here, we explore the hypothesis that the brain acts as a near-optimal inference device that constantly attempts to infer the time-varying matrix of transition probabilities between the stimuli it receives, even when those stimuli are in fact fully unpredictable. This parsimonious Bayesian model, with a single free parameter, accounts for a broad range of findings on surprise signals, sequential effects and the perception of randomness. Notably, it explains the pervasive asymmetry between repetitions and alternations encountered in those studies. Our analysis suggests that a neural machinery for inferring transition probabilities lies at the core of human sequence knowledge.

Sign in / Sign up

Export Citation Format

Share Document