bluuebunny/crossref_metadata_2025 huggingface dataset:
An Apparent New Instance of Stimulus Intensity Dynamism during Discrimination of Duration of Repeating Auditory Stimuli
Authors: Macmillan A. St. C. , Gray J. A. , Ison J. R.
Published: July 2007

Rats were trained on a VI/EXT discrimination using barpressing in a Skinner box for food reinforcement. The discriminanda consisted of different proportions of noise to silence within a fixed 3-s noise-plus-silence repeating cycle. These stimuli were easily discriminated by human subjects, but the rats formed the discrimination only poorly and after considerable training. Analysis of response rates during noise and silence separately within the 3-s noise-plus-silence cycle showed higher response rates during noise, irrespective of whether this was during the positive or during the negative stimulus, or whether relatively long duration of noise or relatively short duration of noise (within the 3-s cycle) constituted the positive stimulus. These results are seen as providing an instance of the dynamogenic effects of stimulus intensity on response vigour to which the Perkins-Logan generalization of inhibition hypothesis of stimulus intensity dynamism cannot apply.
Effects of Stimulus Duration and Intensity on the Rate and Specificity of Behavioural Habituation
Authors: File Sandra E.
Published: July 2007

Tone stimuli were presented to rats once per day until habituation was reached. Neither the duration nor the intensity of the stimulus affected the rate of habituation. Habituation was specific to both these stimulus parameters as shown by the distraction produced by either an increase or a decrease in the original stimulus value. It is suggested that some of the discrepancies in the literature might be resolved if a distinction is drawn between habituation of orienting responses and the decrement of more specific responses.
Stimulus Array and Recall Method as Variables in Audio-Visual Split-Span Memory
Authors: Hede Andrew J.
Published: July 2007

Performance on an audio-visual split-span task was found to be adversely affected by the concurrent operation of two factors, namely: alternation of stimulus classes between the two input messages, and the use of a recall method which entails alternate sampling of the two messages. However, these factors had no significant effect when operating singly. The present study indicated that subjects prefer the strategy of reporting visual items first when using modality recall, and that this strategy is more efficient than that of reporting auditory items first. Also, modality recall proved to be the preferred method under free recall instructions. While there were more visual errors than auditory errors, visual commissions exceeded order errors, but auditory order errors exceeded commissions. The redundancy proposal of the search hypothesis (Yntema and Trask, 1963) was tested, and was found to be inadequate as an account of audio-visual performance.
Visual Onset and Offset Latencies
Authors: Walsh T.
Published: July 2007

An experiment was designed to test the hypothesis that the latency of response to the offset of light can sometimes be shorter than the latency of response to the onset. The subjects’ task involved the temporal order discrimination of the offset of one light and the onset of another. The results indicated that offsets were perceived about 40 ms earlier than onsets. Reasons were suggested for the shorter onset latencies found by other investigators, and a model was proposed to account for changes in the relative latencies of onsets and offsets as a function of stimulus duration and intensity.
Reaction Time and Short-term Memory: Implications of Repetition Effects for the High-speed Exhaustive Scan Hypothesis
Authors: Baddeley Alan D. , Russell Ecob J.
Published: July 2007

Recognition memory for sub-span digit sequences was investigated using Stern-berg's varied-set RT technique. Two experiments studied memory for sequences containing repetitions (e.g. 9 1 9 3) and observed faster recognition of repeated items. Experiment I also showed serial position effects with faster responding to more recent items. Neither of these effects is predicted by Sternberg's highspeed exhaustive scanning hypothesis. Several alternative hypotheses are considered, including two models based on the concept of trace strength, which appear to merit further investigation.
Effects of S-R and R-R Compatibility on Bimanual Movement Time
Authors: Annett John , Sheridan Martin R.
Published: July 2007

Bimanual asymmetrical movements are generally found to be slower than symmetrical movements but asymmetrical movement normally involves visual separation of targets which might account for the effect. By using a system in which the subject controls two cursors on an oscilloscope screen by moving two levers the S-R relationship on either hand can be reversed, thus providing an asymmetrical movement task without visual separation of targets. Movement times for five right-handed subjects were recorded on four unimanual and six bimanual conditions varying with respect to both S-R and R-R compatibility. In the unimanual conditions, the left hand was found to be as fast as the right when the opposite S-R relationship was used. In the bimanual tasks visual separation of targets was a relatively minor factor movement time being strongly influenced by S-R compatibility and to a lesser degree by R-R compatibility. The results suggest that compatibility, rather than being a property of a single central channel, differs, as between the two cerebral hemispheres.
Variations in Size Judgements as a Function of Surface Texture
Authors: Newman Colin V.
Published: July 2007

Adult subjects made monocular size judgements in two experiments in which the independent variables of surface texture and restrictions on viewing conditions were manipulated. Texture density gradients of stimulation had a significant influence of size judgements only under the less reduced conditions of observation when subjects could see other textured surfaces beyond the surfaces over which judgements were made. Identical manipulations of surface texture had earlier been found to have a highly significant influence on relative distance judgements (Newman, 1971). The principally negative results were thus taken to imply that subjects extract different information from the texture density gradient when judging size from that extracted when judging relative distance.
The Effects of Adaptation to Gratings on the Perceived Orientation of Single Lines
Authors: Parker D. M.
Published: July 2007

Subjects were adapted for 45 s to a 5 cycle per degree grating, tilted 10° from the vertical, and at one of four levels of luminance contrast. Estimates of the slope of the grating, or of a single line which replaced the grating, were obtained before and after the period of adaptation by the subject's setting of a single reference line which was located 3° from the edge of the grating. In Experiment I the fixation area was at the centre of the grating, so that half of the grating fell on each retinal hemifield. The reference line was set to a tilt further from the vertical following the period of adaptation, indicating either a change in the apparent orientation of the grating or the reference line. In Experiment II, where the fixation area was midway between the grating and the reference line, so that line and grating appeared in different hemifields, settings indicated no change in the tilt of the grating. In Experiment III, where the fixation area was again midway between grating and setting line, but where the grating was replaced by a single line after the adaptation period, settings indicated that the line had decreased in apparent tilt. The results of the three experiments indicate that while gratings either do not normalize or do so to an insignificant extent they produce a substantial amount of normalization on a single line. Comparison of the results of Experiments I and II shows that spread of this effect outside the directly adapted area is less across the naso-temporal division of the retina than within the same hemifield.
Visual Imagery and Verbalization with Simple Tachistoscopic Displays
Authors: Grindley G. C. , Townsend Valerie
Published: July 2007

Two experiments, designed to compare the perception and retention of tachisto-scopic displays of four block capital letters and four simple “nonsense” figures are described. The results show that the letters were much better remembered and suggest that this was mainly due to the ease with which they were verbalized. The nonsense figures usually gave rise either to rapidly fading “iconic” images, or to an unstable kind of mixed imagery which was difficult to describe or remember, but in which inadequate verbalization was often a source of error. Subsidiary experiments illustrate the importance, not only of verbalization, but also of symmetry and simplicity in remembering visual display.
Immediate Memory for Faces: Long- or Short-Term Memory?
Authors: Warrington Elizabeth K. , Taylor Angela M.
Published: July 2007

Immediate recognition memory span and short-term forgetting for non-verbal stimuli (“unfamiliar faces”) were investigated in normal subjects and amnesic patients. Surnames were used as a verbal control. It was found that normal subjects had a reliable immediate recognition span of one for faces and that there was no decrement in performance in the retention of three faces over a 30-s interval. Amnesic subjects were impaired on both the immediate memory span task and on the short-term forgetting task. This pattern of results contrasts with those obtained using surnames on which the results were comparable to other verbal S.T.M. tasks. It is suggested that performance on these tasks of recognition memory for faces is determined by L.T.M. processes. The implications for the interpretation of S.T.M. are discussed.
Evoked Potentials in Reaction Time with a Variable Foreperiod
Authors: Boddy John
Published: July 2007

The reaction times (RTs) of 12 subjects were recorded in a design where a visual or auditory warning signal preceded an auditory RT signal by one of four short foreperiods 500, 750, 1000 or 1250 ms long, which occured in a random sequence. For the 16 trials at each foreperiod, with each modality of warning signal, the average of the 2-s long EEG samples following the warning signal was computed so that the record showed the scalp recorded (vertex–-left mastoid) evoked potentials (EPs) to both warning and RT signals, and also the contingent negative variation or expectancy wave occurring during the foreperiod.

Differences between RTs with different foreperiods were not reflected in negatively correlated differences in the amplitude of the RT signal EPs, taking the major positive going deflection between peaks N1 and P2 at mean latencies of 126 and 231 msec after the RT signal. Furthermore RT signal EPs preceded by a warning signal were highly attenuated in amplitude relative to control EPs which were not preceded by a warning signal, whether or not an RT response was required. This was despite the fact that alerted RTs were slightly faster than non-alerted RTs, so that these findings contradict previous findings associating augmented EPs with responding versus not responding and with speeded RTs.

However, it was also found that RT signal EP amplitudes were greater with the more effective modality of warning signal than the less effective, which was consistent with previous findings. The divergence from previous findings when comparing EPs preceded by a warning with those having no prior warning is tentatively accounted for in terms of persisting physiological refractoriness following the warning signal EP.
Effects of a Timing Signal on Simple Reaction Time with a Rectangular Distribution of Foreperiods
Authors: Requin Jean , Granjon Marilyn , Durup Henri , Reynard Guy
Published: July 2007

It was hypothesized that the time course of preparation during a variable interstimulus interval (ISI) of a simple reaction time (RT) experiment was partly determined by the subjective distribution of conditional probabilities of the executive signal (ES). Sixty subjects performed a simple auditory RT task with various ranges of six ISI durations organized in rectangular frequency distributions. In order to give the subjects information about elapsed time during ISI, a recurring time-marking click, the periodicity of which was varied, was introduced during the ISI in one of the three series of trials each subject performed. A strong decreasing RT–-ISI relationship was observed supporting the main hypothesis. However, a clear increase of mean RT over all ISIs combined, was also found. Because these two mixed effects were greatest when the click intervened at the possible times of ES occurrence only, three functions of time-information given by the click are discussed: (a) a reduction of the usual increase of time estimation error with increased ISI; (b) an increase of the subjects knowledge of the ISI range resulting from the discontinuity of the time-marking click which makes easier a discrete time-intervals numbering process; (c) a change of the simple-RT task into a discrimination task.
Olfactory Conditioning by Association with Histidine-Free or Balanced Amino Acid Loads in Rats†
Authors: Simson P. C. , Booth D. A.
Published: July 2007

An histidine-devoid but otherwise balanced amino acid mixture depressed food intake from 2 hr after its gastric intubation. It induced conditioned aversion to an odour incorporated in a protein-free diet presented for 6 h following intubation. In other rats, a balanced amino acid mixture established conditioned preference for odour presented in the same diet for 6 h following intubation. The degree of preference was considerably less than the degree of aversion.
An Improved Technique for Monitoring Fixation in Tachistoscopic Tasks
Authors: Maddess Ralph J. , Rosenblood Lorne K. , Goldwater Bram C.
Published: July 2007

A monocular lens mounted behind a stimulus screen was used to monitor fixation in a tachistoscopic recognition task. This technique was found superior to the often used “sideview technique” and as accurate as the method involving identification of a fixation stimulus. It was found that the “telescope technique” is preferable in those studies where presentation of a fixation stimulus might interfere with recognition or report of the experimental stimulus.
A Note on Cross-Modality Matching
Authors: Auerbach Carl
Published: July 2007

“Stevens' law”, that the psychophysical law is a power function, is often taken to be confirmed by results of cross-modality matching experiments, for it predicts both the fact that cross-modality matching experiments yield power functions, and the exponents of these power functions. Both these predictions, however, follow from a more general form of the psychophysical law, of which Fechner's law is a special case. In view of this, an interpretation of cross-modality matching based on stimulus discriminability rather than sensation magnitude is proposed.
A Preliminary Study of Distinctive Features in Problem Solving
Authors: Wood David , Shotter John
Published: July 2007

The abstract logical structure of family relationship problems, such as, “What relationship to a man is his mother's father?” was described in terms of a “distinctive-feature-transition count (dft)”, where the answer to the problem was characterized in terms of the distinctive features of descendancy, co-linearity, and sex. On average, it proved possible to predict the difficulty of such problems from such a count; thus tending to support the idea of a relational rather than an associative memory structure.
The Oblique Line Illusion: The Poggendorff Effect without Parallels
Authors: Day R. H.
Published: July 2007

The apparent misalignment of two oblique collinear lines was investigated in two experiments. In the first the effect with the lines at 45° to the median plane was compared with that for the same two lines separated by the conventional parallels of the Poggendorff figure. The illusion with the two lines was consistent and significant but about one-third the magnitude of that with the parallels. The two illusions were significantly correlated. In the second experiment the angle of the two oblique, collinear lines was varied in 15° steps. The misalignment illusion was maximal at 45° and smaller but significant at 60 and 75°. There was no significant effect at 15 and 30°.
How Are Pictures Registered in Memory?
Authors: Cohen Gillian
Published: July 2007

Three experiments tested the hypothesis that pictorial memory is much less dependent on rehearsal than is verbal memory. Experiment I examined incidental learning since this is assumed to reflect learning with little or no rehearsal. Following a classification task, intentional and incidental learning for pictures and for words was compared. The superiority of pictorial memory was especially marked in incidental learning. Experiment II showed that this result was not due to differences in the amount of processing required to classify pictures and words. RTs to classify words and pictures did not differ, and incidental learning was again superior for pictures. In Experiment III rehearsal opportunity was restricted by a concurrent task during presentation of word and picture lists, and the decrement was very much greater for word learning than for picture learning. It was concluded that manipulation of rehearsal opportunity has relatively little effect on pictorial memory.
An Inexpensive Response-Reading Head for Use with Carousel Slide Projectors and Serial Anticipation Tasks
Authors: Wade Edward A. , Dixon Donald W. , Meissner David C.
Published: July 2007

An inexpensive response-reading head, using a binary code, is described. It can be attached to Carousel projectors and provides for the automatic recording of responses, response latencies, etc. in serial anticipation tasks.
An Experimental Study of Linear Inclination
Authors: Fisher Gerald H.
Published: July 2007

Two mechanisms have been proposed to account for perceptual distortion of angular subtension. The first implies that errors made when estimating sizes of angles should correspond to inaccuracies of estimating the inclinations of their two component lines. From the second it follows that the two types of judgement are unrelated. This paper considers which of these mechanisms accounts most consistently for apparent angular distortion. Two experiments are reported. In the first, four independent groups of subjects estimated the bearing of a single straight line presented in a series of inclinations throughout the entire circular range. Subjects themselves attempted to place the same line into specified inclinations in the second experiment. The results reveal errors in both tasks. An attempt is made to distinguish between the two proposed mechanisms by predicting angular distortions from those of corresponding linear inclinations. Possible reasons for failure of this prediction are discussed.
The Effect of Non-Verbal Information on the Recall of Negation
Authors: Engelkamp Johannes , Hörriann Hans
Published: July 2007

The influence of non-verbal information on storage of different versions of negated sentences was investigated in a one-trial learning experiment. The negation governed either the subject, the object, or the predicate of the sentence. One group was presented with the sentences together with pictures. Another group the sentences only. The picture which was shown with a sentence represented the sentence content with an alternative for the negated concept. It was found that pictorial information had an effect on the recall of the sentences and that this effect is different for the different sentence versions.
Tachistoscopic Recognition of Syllabicated Words
Authors: Manelis Leon , Atkinson Richard C.
Published: July 2007

In Experiment I, two-syllable words were presented in a multi-channel tachisto-scope. The whole word (W), first syllable (S1), and second syllable (S2) were displayed independently according to various schedules of successive 50-ms exposures; the exposures were in immediate succession, with no break apparent to the subject. Accuracy of identifying the words was facilitated by presenting a syllable before or after the whole word (S1W, S2W or WS1, WS2) in comparison with presenting the whole word alone (W). Presentation of the whole word for 100 ms (WW) produced better performance than sequential presentation of the first syllable, the whole word, and the second syllable for 50 ms each (S1WS2); the whole-word presentation (WW) was also superior to the reverse sequence (S2WS1). In Experiment II, strings of random digits were presented in the formats of S1WS2, WW, and S2WS1. Unlike the results of Experiment I, performance in the sequential conditions was not different from that in the simultaneous condition. It was concluded that sequential tachistoscopic presentation does not affect identification of unrelated characters, although it does disrupt the process of word recognition. Three hypotheses to explain the disruption were discussed: distortion of phonological representation, interruption of medial letter clusters, and fragmentation of the whole word.
Effects of Food Deprivation upon Cue Utilization as Measured by Novelty-Incentive
Authors: Hoyenga Kermit T. , Hoyenga Katharine Blick
Published: July 2007

A series of three experiments was done to test the hypothesis that high levels of food deprivation would adversely affect cue utilization from a complex stimulus goal as tested by its novelty-incentive value when that goal was later opposed to food for hungry subjects in a T-maze. It was found that the hunger drive level under which the male rats had originally experienced the complex stimulus goal determined its later incentive value, whether the original experience was in a latent learning type II situation (Experiment I, 20 subjects), a drive-shift situation (Experiment II, 40 subjects), or a free exploration situation (Experiment III, 30 subjects). In each experiment, having first experienced the complex goal under low levels of deprivation significantly decreased the frequency of choices of that goal in a later test relative to the performance of the more deprived animals. The data was interpreted as indicating that utilization of cues, in the sense of input and possibly retention of information, was hindered by the higher levels of deprivation.
The Role of Posture in Sound Localization
Authors: Lackner James R.
Published: July 2007

Studies of auditory localization revealed that where a subject hears a sound is dependent on both his perceived head position and the auditory cues at his ears. If an error is induced between his true and registered head posture, then errors in his auditory localizations of corresponding size and time course result. The presence of visual information prevents the development of postural errors and, consequently, prevents the development of errors in auditory localization, too. These observations are related to the oculogravic illusion and are interpreted as one aspect of the functioning of a spatial reference system involved in the maintenance of the constancies of auditory and visual detection.
Parallel but Temporally Displaced Visual Half-Field Metacontrast Functions
Authors: McKeever Walter F. , Suberi Max
Published: July 2007

Using a classic letter-ring metacontrast paradigm, left and right visual field meta-contrast functions were separately determined. The parallel U-shaped recognition functions for both half-fields were found to interact differentially with stimulus onset asynchrony, the left visual field function being displaced by 13 ms toward longer test stimulus-masking stimulus separations. This result was consistent with the hypothesis of longer processing time requirements for verbal stimuli delivered to the right than to the left hemisphere. This indicates that the neural locus (loci) responsible for left visual field verbal processing delay is (are) capable of mediating metacontrast phenomena. It was tentatively concluded that a relative processing delay within the right hemisphere underlies the differing visual half-field metacontrast interaction with stimulus onset asynchrony.
The Effect of Repetition on Iconic Memory
Authors: Merluzzi Thomas V. , Johnson Neal F.
Published: July 2007

The present experiment examined the influence of repetition on iconic memory using the Sperling (1960) procedure. It was assumed that the whole-report procedure would estimate only information available from a somewhat more permanent memory system than the icon, while the partial report would estimate both that information and the information available in the icon. The difference between the whole and partial report was assumed to measure information available only in the icon. Across a series of 160 displays one particular display occurred half the time (80 repetitions). The results indicated that the repetition influenced recall from the more permanent memory system assessed by whole report, but had no influence on the information available from the icon (partial report minus whole report).
Facilitation of Letter Recognition by an Annulus in a Metacontrast Paradigm
Authors: Matthews Michael L.
Published: July 2007

The recognition of a single letter is found to improve when it is surrounded by an annulus in close proximity. This facilitatory effect is obtained only when annulus and target durations are equal and onsets are simultaneous. When the annulus is increased in size, the facilitatory effect is found first to increase in magnitude and then to decline; no interaction between target letter and annulus is observed for large diameter annuli (72′+). The results are interpreted with reference to a lateral inhibitory model of spatio-temporal interactions.
Concrete and Abstract Terms and Relations in Testing a Rule
Authors: Gilhooly K. J. , Falconer W. A.
Published: July 2007

Subjects have more difficulty in correctly testing a conditional rule stated in abstract form than the same rule given in “thematic” form. The “thematic” form of the rule involves both concrete terms and a concrete relation. Four experimental conditions were formed by combining concrete abstract terms and relations. Fifty subjects were tested in each condition. The results indicated that concrete-ness of the terms is the main factor leading to improved performance with “thematic” as against abstract material in the rule testing task.
Salience, Induced Muscle Tension, and the Ability to Ignore Irrelevant Information
Authors: Folkard Simon , Greeman Adrian L.
Published: July 2007

Two experiments are described that examined the effects of salience and induced muscle tension on subjects' ability to ignore irrelevant information in card sorting tasks. The results of the first experiment suggested that even though the responses appropriate to the relevant and irrelevant information were unrelated there was an effect of irrelevant information, but only when it was more salient than the relevant information. Induced muscle tension was found to improve performance based on less salient attributes but to degrade performance based on more salient attributes. The second experiment confirmed this latter finding using a version of the Stroop test. It is tentatively suggested that induced muscle tension may inhibit naming responses.
Moray vs. the Rest: The Effects of Extended Shadowing Practice
Authors: Underwood Geoffrey
Published: July 2007

The processing requirements of the shadowing response have led to criticisms of its use in selective attention experiments. The present experiment tested a single highly skilled shadower (N. Moray) using a task requiring the detection of digits embedded in dichotic lists of letters, with attention being directed to one list by use of the shadow technique. This subject was able to detect considerably more digits in both the attended and unattended messages than were groups of unskilled shadowers previously tested. Although performance to the unattended message was high, it remained below performance to the attended message.
The Effects of Physostigmine during the Acquisition of Avoidance Behaviour as a Function of the Intersession Interval
Authors: Cox Tom
Published: July 2007

Rats were trained and tested on an avoidance task in a shuttle box. The change in the performance of the control rats over two sessions was found to be a U-shaped function of the interval between the sessions. The change in performance of rats injected with physostigmine prior to the second session was also found to be a U-shaped function of the intersession interval, although the drug was shown to impair avoidance behaviour. These results are consistent with those of Hamburg (1967) and of Biederman (1970), and support the general contention that cholinergic mechanisms in the brain are involved in the control of avoidance and escape behaviour in the rat. They do not, however, necessarily support the hypothesis advanced by Deutsch (1969, 1971) to describe a biochemical basis of learning and memory, especially if it is used to explain the effects of cholinesterase inhibitors on avoidance behaviour in the shuttlebox.
Attending to Visual or Auditory Verbal Information While Performing Other Concurrent Tasks
Authors: Wright P. , Holloway C. M. , Aldrtch A. R.
Published: July 2007

Investigation of the effect that a word recognition task has on concurrent nonverbal tasks showed (a) auditory verbal messages affected visual tracking performance but not the detection of brief light flashes in the visual periphery, (b) greater impairment, both of tracking and light detections, when verbal messages were visual rather than auditory. With a kinaesthetic tracking task, errors increased significantly during auditory messages but were even greater during visual messages. There was no interaction between the modality of tracking error feedback (auditory or visual) and the modality of the verbal message. Nor was the decrement from visual messages reduced by changing the presentation format. It is suggested that different temporal characteristics of visual and auditory information affect the attentional demands of verbal messages.
Expectancy in Educable Subnormal Children and Their Normal Mental Age Controls
Authors: Folkard Simon
Published: July 2007

The long reaction times of mentally subnormal children have commonly been attributed to an inability to build up an adequate preparatory set. The experiment reported attempted to test this suggestion by comparing the ability of normal and subnormal children to anticipate a regularly occurring event. The performance of educable subnormal (ESN) children was found to be inferior to that of normal children matched on mental age (NMA) both in terms of the accuracy and the variability of their anticipations. However, this inferiority disappeared when visual input was restricted to the relevant events. It is concluded that ESN children suffer both in the accuracy and in the variability with which they estimate time intervals. It is suggested that these deficits may be mediated either by a relatively high level of distractability or by a relatively low level of arousal.
Two-flash Threshold, Sensitivity and β in Normal Subjects and Schizophrenics
Authors: Gruzelier J. H. , Venables P. H.
Published: July 2007

Two-flash threshold, response criterion, and sensitivity (defined by the slope of the psychophysical ogive), were examined in schizophrenics and in normals under three conditions—a base-line condition, and during and after continuous white noise. Schizophrenics were subdivided into four groups on the basis of whether or not they exhibited paranoid symptomatology and electrodermal orienting responses. In general schizophrenics had more lenient two-flash response criteria than normal subjects. In the base-line condition schizophrenics with orienting responses had lower two-flash thresholds than those without orienting responses. Paranoid schizophrenics had more lenient criteria than non-paranoid schizophrenics and lower sensitivity than the non-paranoid group with orienting responses. Differential group effects were obtained during and after noise, especially with regard to sensitivity.
In Defence of Iconic Memory
Authors: Coltheart Max , Lea C. David , Thompson Keith
Published: July 2007

According to a model of visual information-processing which originated with Sperling (1960), and which currently enjoys wide acceptance, the contents of brief alphanumeric displays are initially held in a high-capacity fast-decay visual-information store (“iconic memory”). Some of these items are subsequently transferred to a more durable form of storage; the remaining non-transferred items are lost. Observers can select which items are to be transferred on the basis of physical characteristics of the items (such as colour, location, size, shape or brightness).

This model has recently been attacked by Holding (1970, 1971, 1972, 1973), sometimes by claiming that iconic memory does not exist, and at other times by claiming that transfer from iconic memory cannot be selectively controlled by the observer. We argue in this paper that Holding's criticisms are incorrect, and that, even if they were correct, the experiment we report would not be open to objections he has raised concerning previous studies of iconic memory. Despite this, evidence fully supporting the orthodox model was obtained, and we therefore conclude that this model remains tenable.
Post-Cueing after Erasure of the Icon: Is There a Set Effect?
Authors: Smith Marilyn C. , Fabri Peter
Published: July 2007

Recognition accuracy in a tachistoscopic identification task typically declines as the size of the set from which the target was selected increases. To determine whether this effect is due to selective encoding from iconic store, a masking stimulus, intended to erase the icon, was presented following the stimulus. Information about the set was then presented. It was found that subjects' performance in this post-cueing situation did not differ from performance in a pre-cueing condition, where the set was presented prior to the stimulus. It was concluded that set size does not have its effect through selective encoding from iconic store. Results were discussed in terms of the fragment theory.
Word Recognition in a Phonemic Dyslexic Patient
Authors: Shallice Tim , Warrington Elizabeth K.
Published: July 2007

The systems underlying word recognition were investigated in a single case study of a patient (K.F.) with an acquired dyslexia. His reading performance was related to parts of speech, word frequency and word concreteness, and his reading errors were analysed. There was a very striking difference between his ability to read concrete and abstract words. Furthermore visual errors, which could not be attributed to a deficit at a peripheral level, predominated; phonemic errors did not occur. It is argued that these findings support a dual encoding model of word recognition, the present case illustrating the impairment of the phonemic route, a direct graphemic-semantic route being relatively spared. These findings and interpretation are for the most part consistent with Marshall and Newcombe's (1973) studies of acquired dyslexia. The present findings are discussed in terms of more general theories of word recognition.
The Role of Background Stimuli during Pavlovian Conditioning
Authors: Odling-Smee F. J.
Published: July 2007

An investigation was carried out into the part played by background stimuli during Pavlovian conditioning. Groups of rats were presented with tone CSs and unavoidable foot-shock USs. Both CS-US conditional probabilities and US intensity were manipulated across groups. Subsequently all animals were tested for their reactions to the environment in which they had previously been trained. During tests neither the CS nor the US was presented. It was found that the degree to which rats avoided the environment was inversely related to the probability of the CS being followed by a US and directly related to the level of US intensity to which they had been exposed during training. The results largely supported Rescorla and Wagner's (1972) theory of Pavlovian conditioning.
Dichoptic Induction of Mccollough-Type Effects
Authors: Mackay D. M. , Mackay Valerie
Published: July 2007

If left-oblique and right-oblique black/white gratings are presented alternately to one eye, and unpatterned red and green fields are presented alternately to the other, orientation-sensitive chromatic after-effects are induced. With the colour-stimulated eye the hue usually seen on a test grating is complementary to that originally paired with its orientation, with the pattern-stimulated eye the hue is the same as that originally paired.

The experiments reported here show that: (a) the time course of decay of these chromatic after-effects (for each eye) fits approximately the same power law as that found for the normal McCollough effect; (b) analogous chromatic after-effects, opposite in the two eyes, can be dichoptically induced using pairs of stimuli other than gratings, such as dot patterns differing in magnification.

These results suggest that strongly coloured light in one eye can induce a weakly complementary bias in the colour-signalling system of the other eye, at a level peripheral to the site of the McCollough-type adaptation.
Knowledge of Spatial Relations: A Preliminary Investigation
Authors: Wilton R. N. , File Portia E.
Published: July 2007

The mechanism underlying our knowledge of spatial relationships was investigated. In the first experiment subjects were asked to examine an array of circles, located in different positions on a background; after removal of the array, they answered questions about the spatial relations between the circles. The array was constructed so that the number of circles and the number of relations between circles could be independently varied. The results showed that the number of correct answers decreased as the number of circles increased, but was unaffected by the number of relations between circles. This suggests that subjects learn the positions of the circles, from which relations between circles can be computed, rather than learning the relations directly. Evidence from the second experiment, using a similar experimental paradigm, suggests that the positions of the circles are learned by organizing them into higher-order units or groups.
Behavioural Contrast in Discrete-Trial Discriminations: Effects of Non-Reinforcement
Authors: Macphail Euan M.
Published: July 2007

Six pigeons performed an acquisition and three reversals of a discrete trial simultaneous discrimination in which responses to the positive key were reinforced on a fixed-interval 5-s schedule; trials were terminated by either a response to the negative key or the delivery of a reinforcement. In the initial stage of acquisition and each reversal, where errors were most frequent, response rates rose and latencies fell on positive trials; these effects declined as errors decreased. The birds were also run in two yoked control conditions, and results showed that the critical requirement for the positive trial rate and latency changes was neither the simultaneous presentation of two stimuli nor the formation of a discrimination, but the occurrence of non-reinforced responses. The similarity of these phenomena to conventional behavioural contrast is emphasized, and the results are discussed in terms of frustration theory.
Definiteness and Voice in the Interpretation of Active and Passive Sentences
Authors: Hupet Michel , Bouedec Brigitte Le
Published: July 2007

In Experiment I, subjects were given active and passive sentences where the definiteness of nominals is varied and about which uncertainty was expressed, e.g. “I thought that the policeman had been injured by a gangster, but I was mistaken, in fact.”. Their task was to decide what was the target of the mistake by completing freely the sentence in such a way that the account would be corrected. When the nominals are differentially determined (a-the, the-a), the pattern of responses indicates that, for both active and passive, subjects were more likely to conclude that it was the non-definitely marked nominal that had been involved in the mistake rather than the definitely marked one. When both nominals are similarly determined (a-a, the-the), subjects were more likely to indicate the event itself as having been involved in the mistake. This supports the hypothesis that subjects are able to utilize definiteness to determine the relation between presupposed and assertional information. In Experiment II, subjects were given paired active and passive sentences with differentially determined nominals and were required to choose between the two syntactic forms of each pair the one they would prefer to use. The pattern of responses clearly shows that subjects were more likely to choose the voice allowing the hypothesized preferential order “Definitely marked grammatical subject-non-definitely marked grammatical object”. Passive transformational rule is thus interpreted as a particular case of a more general rule specifying the ways in which what is made known (comment) is nested on to what is already assumed to be the case (topic).
Letter versus Dot Stimuli as Tools for “Splitting the Normal Brain with Reaction Time”
Authors: McKeever Walter F. , Gill Kathleen M. , Vandeventer Allan D.
Published: July 2007

Filbey and Gazzaniga (1969) found simple dot-present or -absent reports averaged 35 ms slower for the left than for the right visual field. Other data suggests that verbal processing efficiency differences between the cerebral hemispheres, rather than transcallosal transfer time alone, must be tapped to obtain half-field differences as large as 35 ms. Three experiments were conducted. The first failed to show any half-field differences in vocal RT for dot detection; the second replicated previous reports of significant right field superiority of vocal RT to letter stimuli for right handers, and also showed a substantially smaller half-field difference for left handers; the third experiment, utilizing the fixation control procedure of the second experiment, again failed to show half-field differences for the dot detection paradigm. Differences between the Filbey and Gazzaniga and present results probably reflect important procedural differences. We conclude that transcallosal transfer time for simple dot information is much smaller than assumed by Filbey and Gazzaniga and that the letter report-time task taps hemispheric asymmetries of verbal processing efficiency.
Pictorial Encoding of Sentences in Sentence—Picture Comparison
Authors: Tversky Barbara
Published: July 2007

Subjects are shown to verbally encode sentences for simultaneous comparison with pictures but pictorially encode sentences for later comparison with pictures. This is taken as further evidence that subjects adapt their encodings or representations of stimuli to demands of the task.
Maintaining Recency despite a Stimulus Suffix
Authors: Salter David
Published: July 2007

Two processes of information retrieval were considered in the context of the logogen model. The aim was to establish whether information about the final items of an auditory short-term memory list is held exclusively in precategorical acoustic storage at presentation or whether these items are automatically registered in a cognitive store as well. Error data for a final heterogeneous item in alphanumeric lists showed significantly better recall, despite the addition of a stimulus suffix. Although these results demonstrated that coding had proceeded further than a precategorical stage, which maintains only physical features, the possibility remained that the effect was due to a bias in focal attention and selective coding at list presentation. A second experiment increased the difficulty of the retrieval task, and effectively precluded the possibility of a bias in attention. The results confirmed the findings in the first experiment. It was concluded that information about the final item(s) is registered automatically in the cognitive system, and that responses are made available from this source when information about physical features of the item is degraded by a stimulus suffix.
Stereopsis Maintained with Identical Stimulation to Both Eyes
Authors: Dowrick Peter W.
Published: July 2007

Stereopsis was induced with images cycled alternately to each eye. Presentation was gradually modified until each eye was receiving identical stimulation at any moment in time. It was found possible to maintain stereopsis under the conditions. Variations upon this experiment were devised to auspicate investigation of the conditions underlying this perceptual selection. The implications are discussed from two theoretical viewpoints.
Doubts about Iconic Memory: A Reply to Coltheart, Lea and Thompson
Authors: Holding Dennis H.
Published: July 2007

Replies are made to selected points in the Coltheart, Lea and Thompson (1974) paper. An alternative explanation is given for their experimental results.
The Poggendorff Illusion: Apparent Misalignment which is not Attributable to Apparent Orientation of the Transversals
Authors: Day R. H. , Dickinson R. G.
Published: July 2007

Subjects while looking down were required to adjust a horizontal field of parallel lines (Experiment I) or a single line (Experiment II) to the apparent sagittal direction with and without a superimposed rectangle in the centre of a circular field. The rectangle was tilted at 20, 30 or 40° to the parallels and at 20° to the line. For the 20° condition the parallel lines were apparently oriented at about half a degree compared with the field without a rectangle but in the direction opposite to that necessary to account for the Poggendorff misalignment effect. For the 30 and 40° conditions the lines did not change in apparent orientation. The orientation of the single line did not change. Almost all subjects readily reported an apparent misalignment between the collinear parallels and line separated by the oblique rectangle. It is concluded that the Poggendorff misalignment illusion occurs without apparent regression of the lines to right angles with the figure.
Sex Differences in Rats' Response to Novelty Measured by Activity and Preference
Authors: Russell P. A.
Published: July 2007

Rats were familiarized to one compartment of a test box and then given access to this and a novel compartment. Females spent more time in the novel compartment than males did and this difference was found to be independent of a possible difference in familiarity with the familiar compartment arising from the females' higher frequency of ambulating and rearing with sniffing during familiarization. This is evidence of a sex difference in response to novelty independent of activity differences. Females also had shorter approach latencies to the novel compartment. These sex differences could reflect differences in either fearfulness or curiosity.
Visual Perception of Musical Notation: Registering Pitch Symbols in Memory
Authors: Sloboda John A.
Published: July 2007

Music bears formal relations to language which suggest that perceptual processes in the two modes may also be similar. These experiments examined the way in which experienced musicians differed from non-musicians in their recognition of briefly exposed pitch notation. Experiments I and II together demonstrated that musicians are superior to non-musicians in their immediate written recall of stimuli containing more than three notes, but only when the stimulus is available to them for 150 ms or more. These results are accounted for well by a model proposed by Coltheart (1972) for letter perception under conditions of brief exposure. In this model, two coding processes act simultaneously on the stimulus, one a fast visual coding, and the other a slower, but more permanent abstract (or name) coding. In this case non-musicians appear to be lacking a second, abstract, coding which musicians possess. Experiments III and IV attempted to investigate the nature of the abstract code for musicians by presenting various types of interference in the linguistic or musical mode. Neither concurrent letter naming nor concurrent memorization of pitches appeared to cause a decrement in the original visual task, suggesting that musicians may not have been using simple naming or pitching transformations in coding the visual input.