E. Colin Cherry

Bio: E. Colin Cherry is an academic researcher. The author has contributed to research in topics: Noise figure & Binaural fusion. The author has an hindex of 6, co-authored 6 publications receiving 3782 citations.

Some Experiments on the Recognition of Speech, with One and with Two Ears

Abstract: This paper describes a number of objective experiments on recognition, concerning particularly the relation between the messages received by the two ears. Rather than use steady tones or clicks (frequency or time‐point signals) continuous speech is used, and the results interpreted in the main statistically. Two types of test are reported: (a) the behavior of a listener when presented with two speech signals simultaneously (statistical filtering problem) and (b) behavior when different speech signals are presented to his two ears.

Some Further Experiments upon the Recognition of Speech, with One and with Two Ears

Abstract: The experiments described here continue a series reported in this Journal earlier. A number of objective tests are described, directed towards the general problem concerning the faculty we possess of perceiving only one acoustic world under normal conditions (in spite of having two ears) and yet, if our ears be stimulated by different signals, artificially, we can attend to one or the other of them. The tests have been made with continuous speech (readings from light fiction) and the results assessed statistically. The first tests aim at measuring the reaction time r required to “switch the attention” from one ear to the other, as assessed by perception of the words of the message. A second set of tests show that we perceive only one speaker, as a “gestalt,” when the ears are stimulated by similar messages but with a delay between them exceeding 20 times that ever experienced in real life by virtue of binaural directivity.

Mechanism of Binaural Fusion in the Hearing of Speech

Abstract: The mechanism of binaural fusion is here discussed as a form of statistical operation based upon the brain's execution of running cross‐correlation of the two ear signals. The technique of measurement of the degree of binaural fusion, outlined in our earlier paper, is here extensively applied to sine waves, to chords of sine waves, to intoned vowels and to running speech; such technique results in curves which assess listener's judgments as to whether a source of sound lies in the right or left hemisphere of subjective space. An extended theory is also developed here explaining these judgment curves in detail. Finally, a discussion is made of the importance of having an understanding of the mechanism of binaural fusion, in any consideration of our binaural directivity sense and our speech discrimination sense (the “cocktail, party problem”).

“Human ‘Cross‐Correlator’”—A Technique for Measuring Certain Parameters of Speech Perception

Abstract: A human listener is here regarded as a “cross‐correlator”; his two ears are treated as “input terminals,” stimulated with the acoustic input signals f1(t) and f2(t+τ), while his vocal responses are treated as the output “correlation function” The two signals are, respectively, pure and distorted versions of the same signal (perhaps speech) The delay τ is randomly set and the listener answers right or left, as the source of sound appears to him to lie The “correlation function” then corresponds to the probability distribution of his correct judgments Such functions represent the degree of aural fusion, and show up strikingly the invariants of speech signals which are significant in aural perception

Influence of Noise upon the Equivalence of Intensity Differences and Small Time Delays in Two‐Loudspeaker Systems

Abstract: The equivalence of intensity difference and time delay in two‐loudspeaker systems is greatly affected by the presence of extraneous noise. An experiment is described in which this effect is measured with speech and wide‐band noise. It is found that as the noise level is increased the equivalent intensity difference, for a given time delay, decreases, tending to zero for noise levels approaching the masking level.

Controlled and automatic human information processing: II. Perceptual learning, automatic attending and a general theory.

Abstract: Tested the 2-process theory of detection, search, and attention presented by the current authors (1977) in a series of experiments. The studies (a) demonstrate the qualitative difference between 2 modes of information processing: automatic detection and controlled search; (b) trace the course of the

The magical number 4 in short-term memory: a reconsideration of mental storage capacity.

Abstract: Miller (1956) summarized evidence that people can remember about seven chunks in short-term memory (STM) tasks. How- ever, that number was meant more as a rough estimate and a rhetorical device than as a real capacity limit. Others have since suggested that there is a more precise capacity limit, but that it is only three to five chunks. The present target article brings together a wide vari- ety of data on capacity limits suggesting that the smaller capacity limit is real. Capacity limits will be useful in analyses of information processing only if the boundary conditions for observing them can be carefully described. Four basic conditions in which chunks can be identified and capacity limits can accordingly be observed are: (1) when information overload limits chunks to individual stimulus items, (2) when other steps are taken specifically to block the recoding of stimulus items into larger chunks, (3) in performance discontinuities caused by the capacity limit, and (4) in various indirect effects of the capacity limit. Under these conditions, rehearsal and long-term memory cannot be used to combine stimulus items into chunks of an unknown size; nor can storage mechanisms that are not capacity- limited, such as sensory memory, allow the capacity-limited storage mechanism to be refilled during recall. A single, central capacity limit averaging about four chunks is implicated along with other, noncapacity-limited sources. The pure STM capacity limit expressed in chunks is distinguished from compound STM limits obtained when the number of separately held chunks is unclear. Reasons why pure capacity estimates fall within a narrow range are discussed and a capacity limit for the focus of attention is proposed.

Perception and communication

Abstract: First published in 1958, this book has become recognized as a classic in its field. It marked a transition between behaviourist learning theory and the modern 'information processing' or 'cognitive' approach to perception and communication skills. It continues to provide a principal starting point for theoretical and experimental work on selective attention. As Professor Posner writes in his Foreword to the reissue: 'it remains of great interest to view the work in its original form and to ponder those creative moments when the mind first grasps a new insight and then struggles to work out its consequences.

The role of consciousness in second language learning

Abstract: Richard Schmidt presents on the role of consciousness in second language learning at the 1988 Second Language Research Forum (SLRF) held in at the University of Hawai‘i.