The effect of tone duration on auditory stream formation

In a study in which the effect of tone duration on the formation of auditory streams was investigated, subjects were presented with 15-sec alternating pure-tone sequences (ABAB...) and were asked to orient their attention over the duration of the sequence toward hearing either a temporally coherent or a segregated percept. At stimulus offset, the subjects indicated whether their percept at the end of the stimulus had been that of a temporally coherent ABAB trill or that of segregated A and B streams. The experimental results indicated that the occurrence of stream segregation increases as (1) the duration of the A and B tones increases in unison and (2) the difference in duration between the A and B tones increases, with the duration differences between the tones producing the strongest segregation effects. A comparison of these experimental results with those of other studies strongly suggests that the time interval between the offset and onset of consecutive tones in the same frequency range is the most important temporal factor affecting auditory stream formation. Furthermore, a simulation of the experimental results by the Beauvois and Meddis (1996) stream segregation model suggests that both the tone duration effects reported here and Gestalt auditory grouping on the basis of temporal proximity can be understood in terms of low-level neurophysiological processes and peripheral-channeling factors.     

Electrophysiological evidence of developmental changes in the duration of auditory sensory memory

In behavioral studies, children's memory for tonal frequency has been found to persist for less time than adults' (T. A. Keller & N. Cowan, 1994). The present study was done to evaluate the argument that this effect is due to changes in auditory sensory memory and not to attentional mechanisms. This question was investigated using mismatch negativity (MMN), an auditory event-related potential considered to be insensitive to attention. Participants were 6-7-, 8-10-, and 11-12-year-old children and adults. They were presented with trains of stimuli, beginning with either a standard (1000 Hz) or a deviant (1200 Hz) tone with trains separated by either 1 s or 8 s. All 4 groups exhibited MMNs after delays of 1 s, but only the adults and oldest children exhibited MMNs after 8 s, indicating that there are maturational changes in the duration of auditory sensory memory.     

Recovered memories and false memories.

Review of book: Recovered Memories and False Memories by Martin A. Conway, New York: Oxford University Press, 1997, 301 pp. Reviewed by C. Brooks Brenneis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quantal acetylcholine release induced by mediatophore transfection

Mediatophore is a protein of approximately 200 kDa able to translocate acetylcholine in response to calcium. It was purified from the presynaptic plasma membranes of the electric organ nerve terminals. Mediatophore is a homooligomer of a 16-kDa subunit, homologous to the proteolipid of V-ATPase. Cells of the N18TG-2 neuronal line are not able to produce quantal acetylcholine release. We show here that transfection of N18TG-2 cells with a plasmid encoding the mediatophore subunit restored calcium-dependent release. The essential feature of such a release was its quantal nature, similar to what is observed in situ in cholinergic synapses from which mediatophore was purified.     

Retrieval of emotional memories.

Long-term memories are influenced by the emotion experienced during learning as well as by the emotion experienced during memory retrieval. The present article reviews the literature addressing the effects of emotion on retrieval, focusing on the cognitive and neurological mechanisms that have been revealed. The reviewed research suggests that the amygdala, in combination with the hippocampus and prefrontal cortex, plays an important role in the retrieval of memories for emotional events. The neural regions necessary for online emotional processing also influence emotional memory retrieval, perhaps through the reexperience of emotion during the retrieval process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reinstating preschoolers' memories.

Effects of reinstatement were examined in 2.5-yr-olds' (Exp 1) and 3.5-yr-olds' (Exps 2 and 3) long-term retention. Children learned object–location pairings and, 3 wks later, were provided with postevent information consistent with the originally acquired pairings. One week later (4 wks since acquisition), children were given 4 test trials. Analyses based on the trace-integrity framework indicated that, regardless of age, reinstatement (1) improved children's long-term retention, (2) affected both forgetting and reminiscence, and (3) affected both storage and retrieval processes, in particular, inoculating memories against storage-related forgetting processes. Results were related to recent theories concerning the impact of postevent information on the reliability of storage and retrieval processes that mediate children's long-term recollections. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

My memories of Japanese pediatric neurosurgery

At the end of World War II, medical students in Japan knew that the United States of America were the world leaders in medical science, and they dreamed of establishing such a rational and pragmatic brand of medicine in their own country. As the number of motor vehicle accidents increased in parallel with the raid growth of the Japanese economy after the war, the need for neurosurgery also intensified. The number of papers dealing with pediatric issues increased tremendously after the ISPN and JSPN had first held meetings in Japan in September 1973. It seems mandatory for us to back up the activity of the children's hospitals by establishing a subspecialty of pediatric neurosurgery.     

The reality of repressed memories.

Repression is one of the most haunting concepts in psychology. Something shocking happens, and the mind pushes it into some inaccessible corner of the unconscious. Later, the memory may emerge into consciousness. Repression is one of the foundation stones on which the structure of psychoanalysis rests. Recently there has been a rise in reported memories of childhood sexual abuse that were allegedly repressed for many years. With recent changes in legislation, people with recently unearthed memories are suing alleged perpetrators for events that happened 20, 30, even 40 or more years earlier. These new developments give rise to a number of questions: (1) How common is it for memories of child abuse to be repressed? (2) How are jurors and judges likely to react to these repressed memory claims? (3) When the memories surface, what are they like? and (4) How authentic are the memories? (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Language-dependent recall of autobiographical memories.

Two studies of autobiographical memory explored the hypothesis that memories become more accessible when the linguistic environment at retrieval matches the linguistic environment at encoding. In Experiment 1, Russian-English bilinguals were asked to recall specific life experiences in response to word prompts. The results supported the hypothesis of language-dependent recall: Participants retrieved more experiences from the Russian-speaking period of their lives when interviewed in Russian and more experiences from the English-speaking period of their lives when interviewed in English. In Experiment 2, the language of the interview was varied independently from the language of the word prompts. Both variables were found to influence autobiographical recall. These findings show that language at the time of retrieval, like other forms of context, plays a significant role in determining what will be remembered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)