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Corporate imagination and expeditionary marketing.

In the 1980s, competitive success came mostly from achieving cost and quality advantages over rivals in existing markets. In the 1990s, it will come from building and dominating fundamentally new markets. Core competencies are one prerequisite for creating new markets. Corporate imagination and expeditionary marketing are the keys that unlock them. McKinsey Award winners Gary Hamel and C.K. Prahalad argue that corporate imagination quickens when companies escape the tyranny of their served markets. (Motorola, for example, sees itself as a leader in wireless communications, not just as a maker of beepers and mobile phones). Think about needs and functionalities instead of marketing's more conventional customer-product grid. Overturn traditional price/performance assumptions. (Fidelity Investments unlocked a vast new market by packaging sophisticated investment vehicles for middle-income investors.) And lead customers rather than simply follow them. Creating new markets is a risky business, however--a lot like shooting arrows into the mist. Imaginative companies minimize the risk not by being fast followers but through the process the authors call expeditionary marketing: low-cost, fast-paced market incursions designed to bring the target quickly into view. Toshiba introduced laptop computers to the market at such a blistering pace that it could explore every conceivable niche--and afford an occasional failure without compromising its credibility with customers. To stimulate corporate imagination, top management needs to redefine failure and develop new time- and risk-adjusted yardsticks for managerial performance. Managers must be encouraged to stretch their company's opportunity horizon well beyond the boundaries of its current businesses.

Commerce↗
PubMed2001

Growth factors controlling imaginal disc growth in Drosophila.

In the imaginal discs of Drosophila, contact-dependent cell interactions are important both for promoting cell proliferation and for limiting it at the end of the growth period. However, recent work indicates that diffusible growth factors are also important in regulating growth and proliferation. We have identified a family of five imaginal disc growth factors (IDGFs) by purifying mitogenic proteins that accumulate in conditioned medium during culture of imaginal disc cell lines. These proteins cooperate with insulin to stimulate not only proliferation, but also polarization and motility of imaginal disc cells. They are produced by the fat body and are probably active on a variety of peripheral tissues. The IDGFs are structurally related to chitinases, but they show an amino acid substitution that is known to abrogate catalytic activity and to transform chitinases into lectins. We suggest that these proteins act as endogenous mitogenic lectins and mediate nutritional effects on tissue growth, possibly by interacting with the insulin receptor pathway. Glycoproteins similar to the IDGFs are found in mammals and may constitute a novel class of growth factors and/or inflammatory cytokines.

Animals↗
PubMed1980

In vitro imaginal disc development and moulting hormone.

Imaginal leg and wing discs obtained from late-third-instar Drosophila larvae were cultured in vitro in various concentrations of ecdysterone ranging from 10(-10) to 10(-5) M in order to test the effect of hormone concentration on evagination and cell differentiation. At the optimal concentration of 8 x 10(-8) M discs evaginated normally, secreted the pupal cuticle, underwent apolysis, differentiated imaginal structures and secreted the imaginal cuticle. At suboptimal concentrations (10(-8) M and less), evagination was incomplete in a variable proportion of appendages. Morphogenetic movements were limited to the earlier ones; so that appendages did not emerge from the peripodial sac. Subsequent development, whenever it occurred, took place inside the peripodial sac. This particular type of 'endoevagination' was only obtained with sub-optimal hormone concentration. At supra-optimal concentrations (10(-6) M and more), evagination was always complete but further differentiation was inhibited. These results show that endoevagination is strictly related to insufficient supply of hormone and that morphogenesis and cell differentiation in imaginal discs are two independent phenomena, which respond to different levels of hormone stimulation.

Animals↗
PubMed2004

[The role of imagination in modern medicine].

In Renaissance and early modern times, the concept of imagination (Latin imaginatio) was essential for the (natural) philosophical explanation of magic processes, especially in the anthropology of Paracelsus. He assumed that imagination was a natural vital power including cosmic, mental, phychical, and physical dimensions. The Paracelsians criticized traditional humor pathology ignoring their theory of' 'natural magic'. On the other hand, they were criticized by their adversaries as charlatans practicing 'black magic'. About 1800, in between enlightenment and romanticism, the healing concept of, animal magnetism' (Mesmerism) evoked an analogous debate, whether, magnetic' phenomena originated from a real (physical) power (so-called, fluidum') or were just due to fantasy or imagination (German Einbildungskraft). At the end of the 19th century, the French internist Hippolyte Bernheim created-against the background of medical hypnosis (hypnotism') as a consequence of Mesmerism - his theory of suggestion and autosuggestion: a new paradigm of psychological respectively psychosomatic medicine, which became the basis for the concept of, placebo' in modern biomedicine. From now on, all the effects of, alternative medicine' could easily be explained by the, placebo-effect', more or less founded - at least unconsciously - on fraud.

Europe↗
PubMed2005

Physiological evaluation on emotional change induced by imagination.

In this study, emotional changes were induced by four imaginations--pleasantness, unpleasantness, arousal, and relaxation. They were induced using situations or pictures, as stimuli for imagination, selected on the basis of subjective evaluation and were examined by analyses of the physiological signals of the central and autonomic nervous systems whether the intended emotions were appropriately achieved, and whether these emotional changes could be distinguished from the analysis of physiological signals. While participants were asked to recall each situation (for experiment 1--free recall) or picture (experiment 2--forced recall) of the four imaginations, Electroencephalogram (EEG) in the area of Fz and Cz, Electrocardiogram (ECG), Galvanic Skin Response (GSR), Skin Temperature (SKT), and Respiration (RSP) were measured. The analysis of the EEG revealed that three emotional states were classified by values of alpha/(alpha + beta) and beta/(alpha + beta) and the autonomic nervous system responses, particularly the average interval of R-R and RSP. The results suggest that the values of alpha/(alpha + beta) or beta/(alpha + beta) in the areas of Fz and Cz and the average interval of R-R and/or RSP can be reliable parameters to measure some of the emotional states.

Adult↗
PubMed1991

Motor imagination--a model for motor performances?

The effect of training competition (TC) on central nervous activation was investigated in order to examine whether motor imagination could serve as a model for complex motor skills concerning information processing and motor control. EEG was recorded before and immediately after the TC. The mean alpha frequency (MAF) was computed from the EEG power density spectra. A significant increase of MAF was found after the TC. Similar changes were found during motor imagination. Thus, motor imagination seems to be a good model to examine activation processes.

Electroencephalography↗
PubMed2006

Changes in intrusive memories associated with imaginal reliving in posttraumatic stress disorder.

The study investigated changes in intrusive memories associated with imaginal reliving of traumatic events in posttraumatic stress disorder (PTSD). The study population comprised 44 patients treated with imaginal reliving in the context of cognitive therapy for PTSD [Behav. Res. Ther. 38 (2000) 319-345]. For most patients, imaginal reliving did not lead to exacerbations in intrusion frequency. The decrease in intrusion frequency after reliving was gradual, as was the decrease in their distress, vividness, and perceived "nowness." Poorer outcome, i.e., a smaller reduction in residual gain scores for intrusion frequency with reliving, was associated with greater initial PTSD severity, greater anger, greater perceived "nowness" of intrusive memories, and more negative interpretations of PTSD symptoms. The patient's anxiety, depression, self-blame, and dissociation were not predictive of response to reliving.

Adult↗
PubMed2003

Isolating the retrieval of imagined pictures during episodic memory: activation of the left precuneus and left prefrontal cortex.

The posterior medial parietal cortex and the left prefrontal cortex have both been implicated in the recollection of past episodes. In order to clarify their functional significance, we performed this functional magnetic resonance imaging study, which employed event-related source memory and item recognition retrieval of words paired with corresponding imagined or viewed pictures. Our results suggest that episodic source memory is related to a functional network including the posterior precuneus and the left lateral prefrontal cortex. This network is activated during explicit retrieval of imagined pictures and results from the retrieval of item-context associations. This suggests that previously imagined pictures provide a context with which encoded words can be more strongly associated.

Adult↗
PubMed2006

Modulation of neural activity by angle of rotation during imagined spatial transformations.

Imagined spatial transformations of objects (e.g., mental rotation) and the self (e.g., perspective taking) are psychologically dissociable. In mental rotation, the viewer transforms the location or orientation of an object relative to stable egocentric and environmental reference frames. In imagined shifts of perspective, the viewer's egocentric reference frame is transformed with respect to stable objects and environment. Using fMRI, we showed that during mental transformations of objects the right superior parietal cortex exhibited a positive linear relationship between hemodynamic response and degrees of rotation. By contrast, during imagined transformations of the self, the same regions exhibited a negative linear trend. We interpret this finding in terms of the role of parietal cortex in coding the locations of objects in relation to the body.

Adult↗
PubMed1999

The role of imagination in facilitating deductive reasoning in 2-, 3- and 4-year-olds.

When 4- and 6-year-olds are cued to use their imagination, they can overcome the belief bias effect and demonstrate deductive reasoning ability on syllogisms containing contrary-to-fact material. This study tested whether 2- and 3-year-olds could also reason with incongruent syllogisms when encouraged to use their imagination. Eighty-four 2-, 3- and 4-year-olds were randomly assigned to one of four conditions: no cue, word cue, fantasy planet or imagery. Children were then presented with six syllogistic reasoning problems containing incongruent information. In the imagination conditions, 2- and 3-year-olds performed as competently as 4-year-olds. The findings are discussed in relation to other research which suggests that under certain circumstances 2- and 3-year-olds have the capacity for counterfactual thinking.

Age Factors↗
PubMed2002

Memory for perceived and imagined pictures--an event-related potential study.

Event-related potentials (ERPs) and behavioural measures were used to investigate recognition memory and source-monitoring judgements about previously perceived and imagined pictures. At study, word labels of common objects were presented. Half of these were followed by a corresponding picture and the other half by an empty frame, signalling to the participants to mentally visualise an image. At test, participants in a source-monitoring task made a three-way discrimination between new words and words corresponding to previously perceived and imagined pictures. Participants in an old/new-recognition task indicated whether test words were previously presented or not. In both tasks, correctly identified old items elicited more positive-going ERPs than correctly judged new items. This widely distributed old/new effect was found to have an earlier onset and to be of a greater magnitude for imagined than for perceived items. Task (source versus item-memory) affected the old/new effects over prefrontal areas and the reaction times to remembered old items. The present findings are consistent with the view that a greater amount, or a different type, of information is necessary for accurate source-memory judgements than for correct recognition, and moreover, that different types of source-specifying information revive at different rates. In addition, the results add weight to the view that the late widespread ERP-old/new effect is sensitive to the quality or the amount of information retrieved from memory.

Adult↗
PubMed1999

Cortical potentials during imagined movements in individuals with chronic spinal cord injuries.

A closed-loop model of motor control predicts that central deafferentation should disrupt cortical motor processes when imagining movements of paralyzed limbs. To test this prediction, event-related potentials (ERP) were recorded from the supplementary motor area and the primary sensorimotor area in individuals with paraplegia or quadriplegia as well as able-bodied controls during executed/attempted and imagined movements of the hand and foot. The cross-correlation of ERPs generated during hand movement and imagery was slightly negative for controls, moderate and positive for paraplegics, and high and positive for quadriplegics. The cross-correlation between foot movement and imagery was moderate for controls, moderate to high for paraplegic and high for quadriplegic groups. For hand tasks, ERPs were uncorrelated between controls and quadriplegics; for the foot tasks, the correlations were low between controls and both paraplegics and quadriplegics. Amplitudes and latencies of the ERP were also compared between movement and imagery and between the three injury groups. A biphasic waveform appears prior to and during movements in controls that is absent during imagery and when attempting/imagining movements of paralyzed limbs. Two hypotheses are proposed to explain the differences in cortical processing between movement and imagery and between injury groups. First, cortical motor processes are altered by the absence of kinesthetic feedback during attempted movement of a deafferented limb as well as during imagery. Second, inhibitory processes, present during imagined movements of an intact limb, may be weakened by a spinal cord injury (SCI) so that movement and imagery processes appear isomorphic. While the absence of kinesthetic feedback from deafferented limbs likely contributes to some variability in motor processing, the influence of an SCI on movement inhibition requires further testing.

Adult↗
PubMed2003

Cortical and cerebellar activity of the human brain during imagined and executed unimanual and bimanual action sequences: a functional MRI study.

The neural (blood oxygenation level dependent) correlates of executed and imagined finger sequences, both unimanual and bimanual, were studied in adult right-handed volunteers using functional magnetic resonance imaging (fMRI) of the entire brain. The finger to thumb opposition tasks each consisted of three conditions, two unimanual and one bimanual. Each experimental condition consisted of overt movement of the fingers in a prescribed sequence and imagery of the same task. An intricate network consisting of sensorimotor cortex, supplementary motor area (SMA), superior parietal lobule and cerebellum was identified when the tasks involved both planning and execution. During imagery alone, however, cerebellar activity was largely absent. This apparent decoupling of sensorimotor cortical and cerebellar areas during imagined movement sequences, suggests that cortico-cerebellar loops are engaged only when action sequences are both intended and realized. In line with recent models of motor control, the cerebellum may monitor cortical output and feed back corrective information to the motor cortex primarily during actual, not imagined, movements. Although parietal cortex activation occurred during both execution and imagery tasks, it was most consistently present during bimanual action sequences. The engagement of the superior parietal lobule appears to be related to the increased attention and memory resources associated, in the present instance, with coordinating difficult bimanual sequences.

Adult↗
PubMed1997

Viewer- and object-centered mental explorations of an imagined environment are not equivalent.

In this study we compared viewer-centered (VC) with object-centered (OC) mental exploration of an imagined clock drawn on the ground. An upper case F portrayed on a computer screen was to be imagined standing up in the center of the clock. In Expt. 1, an adjustment task was used to verify that the discrimination of clock directions rendered by this perspective drawing was quite accurate. Precision was not affected by the imaginary size of the clock. In Expt. 2, subjects either (1) indicated the clock location pointed by the F given their viewing position (VC condition), or (2) their location at the periphery of the clock given the location pointed by the F (OC condition). Response latencies were proportional to the explored imaginary distance and increased with the size of the imagined environment. We found an additional mean processing time of at least 2 s in the OC condition with respect to the VC condition. Results are interpreted within Kosslyn's (Kosslyn, S.M., A cognitive neuroscience of visual cognition: further developments. In: R.H. Logie and M. Denis (Eds.), Mental Images in Human Cognition, Elsevier Science Publishers, Amsterdam, 1991, pp. 351-381 [17]) framework of cognitive neuroscience.

Adult↗
PubMed1999

Mental representations of movements. Brain potentials associated with imagination of eye movements.

OBJECTIVE: Current research in motor imagery is focused on similarities between actual and imagined movements on a central and a peripheral level of the nervous system. The present study measured slow cortical potentials (DC-potentials) during execution and internal simulation of memorized saccadic eye movements. METHODS: In 19 healthy righthanded subjects DC-potentials were recorded from 28 electrodes during execution and during imagination of a sequence of memorized eye movements during a visual imagery condition. RESULTS: Both oculomotor conditions showed a similar global level and similar topography of performance related DC-potentials, both strongly differed from the visual imagery condition and were lateralized to the left hemisphere. CONCLUSION: This study therefore supports the hypothesis that cortical brain structures responsible for execution and imagination of memorized saccadic eye movements are similar. The observed left hemispheric lateralization is in contrast to a previous study using bimanual movements. This discrepancy is discussed in relation to recent observations in apractic patients with parietal lesions.

Adult↗
PubMed1978

Functional representations common to visual perception and imagination.

Subjects determined whether probe dots appearing in component squares of a 5 X 5 grid fell on a figure that, depending on the condition, was (a) visually presented as a pattern of darkened squares, (b) only remembered from a preceding presentation of such a pattern, or (c) imaginally generated from a verbal code. The speed and accuracy of the responses to the probes as well as the functional dependencies of the reaction times on structural variables were essentially the same whether the figural pattern was imagined, remembered, or actually seen. Reaction times averaged between 400 and 500 msec and were consistently faster (a) for on-figure than for off-figure responses, (b) for simpler figures that had fewer squares, (c) for off-figure probes that were more distant from the figure, and (d) for on-figure probes that consisted either of more dots on the figure or of a dot at the intersection of a horizontal and a vertical bar. The reults were consistent with a model in which a subject's perceptual or imaginal representations of these forms contain barlike units that respond independently to the probes.

Discrimination, Psychological↗
PubMed1998

Effects of perceiving and imagining scenes on memory for pictures.

Boundary extension is the tendency to remember having seen a greater expanse of a scene than was shown. Four experiments tested whether a picture must depict a partial view of a scene for the distortion to occur. The premise was that partial views activate a perceptual schema, a representation of the expected scene structure outside the view. Participants were 473 undergraduates. Experiments 1 and 2 tested recognition memory and recall of 16 outline-objects presented in outline-scenes versus presentation on blank backgrounds. Experiments 3 and 4 compared memory for outline-objects when scene context was or was not imagined. Boundary errors consistent with the perceptual schema hypothesis only occurred for partial views (perceived or imagined). Results suggest that scene perception and imagination activate the same schematic representation.

Female↗
PubMed2000

Updating displays after imagined object and viewer rotations.

Six experiments compared spatial updating of an array after imagined rotations of the array versus viewer. Participants responded faster and made fewer errors in viewer tasks than in array tasks while positioned outside (Experiment 1) or inside (Experiment 2) the array. An apparent array advantage for updating objects rather than locations was attributable to participants imagining translations of single objects rather than rotations of the array (Experiment 3). Superior viewer performance persisted when the array was reduced to 1 object (Experiment 4); however, an object with a familiar configuration improved object performance somewhat (Experiment 5). Object performance reached near-viewer levels when rotations included haptic information for the turning object. The researchers discuss these findings in terms of the relative differences in which the human cognitive system transforms the spatial reference frames corresponding to each imagined rotation.

Adult↗