Imaging the future: Does a qualitative analysis add to the picture?

Various studies report that patients with dense amnesia experience difficulties in simulating future events. It is argued that this resembles an inability to remember past episodes in that both indicate a deficit in mental scene construction. Such findings, however, rely upon quantitative content-based analyses of participants' verbal reports. Here, samples of verbal reports produced by participants with hippocampal lesions are subjected to a qualitative, discourse analysis of how participants and researchers negotiated the status of these reports. This shows that failure in mental scene construction can be viewed as an interactional achievement rather than the mere reporting of mental events. A multidisciplinary perspective which combines qualitative analysis with other forms of analytic technique may explain subtle differences between participants with hippocampal lesions and control participants.     

Selection history-driven signal suppression

ABSTRACT

The control of attention is influenced by current goals, physical salience, and selection history. Under certain conditions, physically salient stimuli can be strategically suppressed below baseline levels, facilitating visual search for a target. It is unclear whether such signal suppression is a broad mechanism of selective information processing that extends to other sources of attentional priority evoked by task-irrelevant stimuli, or whether it is particular to physically salient perceptual signals. Using eye movements, in the present study we highlight a case where a former-target-colour distractor facilitates search for a target on a large percentage of trials. Our findings provide evidence that the principle of signal suppression extends to other sources of attentional priority beyond physical salience, and that selection history can be leveraged to strategically guide attention away from a stimulus.     

The contribution of the human medial temporal lobe to perception: bridging the gap between animal and human studies.

The medial temporal lobe (MTL) has been considered traditionally to subserve declarative memory processes only. Recent studies in nonhuman primates suggest, however, that the MTL may also be critical to higher order perceptual processes, with the hippocampus and perirhinal cortex being involved in scene and object perception, respectively. The current article reviews the human neuropsychological literature to determine whether there is any evidence to suggest that these same views may apply to the human MTL. Although the majority of existing studies report intact perception following MTL damage in human amnesics, there have been recent studies that suggest that when scene and object perception are assessed systematically, significant impairments in perception become apparent. These findings have important implications for current mnemonic theories of human MTL function and our understanding of human amnesia as a result of MTL lesions.     

The contribution of the human medial temporal lobe to perception: Bridging the gap between animal and human studies

The medial temporal lobe (MTL) has been considered traditionally to subserve declarative memory processes only. Recent studies in nonhuman primates suggest, however, that the MTL may also be critical to higher order perceptual processes, with the hippocampus and perirhinal cortex being involved in scene and object perception, respectively. The current article reviews the human neuropsychological literature to determine whether there is any evidence to suggest that these same views may apply to the human MTL. Although the majority of existing studies report intact perception following MTL damage in human amnesics, there have been recent studies that suggest that when scene and object perception are assessed systematically, signifi-cant impairments in perception become apparent. These findings have important implications for current mnemonic theories of human MTL function and our understanding of human amnesia as a result of MTL lesions.     

Memory in pediatric patients undergoing conscious sedation for aversive medical procedures.

This study investigated preserved memory in 26 pediatric cancer patients (65% boys, 77% Caucasian, mean age = 12.5 years) undergoing midazolam-induced conscious sedation during painful medical procedures to treat hematological or oncological diseases. The sedative midazolam had a significant anterograde amnesic effect on participants' performance on a visual recognition (explicit) memory task but not on a visual perceptual facilitation (implicit) memory task. That implicit memory scores were relatively unaffected while explicit memory scores deteriorated significantly indicates that leaning occurred while participants were sedated, even when participants did not recollect the learning event. These findings, which replicate those of M. R. Polster, R. A. McCarthy, G. O'Sullivan, P. A. Gray, and G. R. Park (1993) in a study of adults, have implications for the development and treatment of conditioned anxiety reactions associated with aversive medical procedures.