Also found in: Dictionary, Thesaurus, Medical, Legal, Wikipedia.


1. Med any delayed response to a stimulus or agent
2. Psychol any illusory sensation caused by a stimulus that has ceased



the change in the state of strain of a solid in a constant stressed state. A simple case of the aftereffect can be observed in a cylindrical specimen acted on by a constant tensile force P, as illustrated in Figure 1. With time, the strain in the rod increases, (curve ab), and in the general case there is an increase in both the elastic and the plastic deformation. This phenomenon is called the direct aftereffect. The increase in elastic deformation is a manifestation of the elastic aftereffect, and the increase in plastic deformation indicates creep. If at some moment t1 the load is removed, the specimen is immediately shortened to the extent of the elastic deformation (bd), and then a slow contraction of the specimen with time (de)—the reverse aftereffect—is observed.

Figure 1. The elastic aftereffect in a material

The elastic aftereffect without creep is observed in solids whose stressed state nowhere exceeds the elastic limit, and it is classified as a slow reversible process. The elastic aftereffect is usually due to the nonuniformity of the elastically stressed state of actual solids and to the tendency of the stressed state to equalization. The aftereffect explains the phenomenon of elastic hysteresis. For metals, the elastic aftereffect is small, but in organic substances—such as leather, textile fibers, and plastics—it can be of considerable magnitude.

The plastic aftereffect in materials, or creep, is associated with a substantial change in the molecular or crystalline structure of materials and ultimately is a consequence of atomic rearrangements. Aftereffects are investigated in rheology.


References in periodicals archive ?
Paired t-tests were used to determine whether the aftereffect was significant (i.
This discovery reveals that the Motion Aftereffect illusion is not just a compelling visual oddity: It is caused by neural processes that happen essentially every time we see moving objects.
However, paying attention to a feature not directly concerned with movement apparently does not influence motion aftereffects, Chaudhuri says.
Of the 20 who said they were suffering aftereffects, 11 said they are still unable to eat curry.
Caption(s): High fuel costs and aftereffects of last year's hurricanes hampered Dollar General's performance.
But the aftereffects of the labor dispute industrial products and material are still disrupting the flow of the goods.
The group was formed to support Nguyen Viet and Nguyen Duc, who were born conjoined at the lower halves of their bodies, possibly due to aftereffects of the released defoliant.
Standard theories of how species arise suggest such a possibility: Mating signals diversify as aftereffects of animals' adapting to different environments.
Lucy Liu on the aftereffects of the kiss she shared with Calista Flockhart on Ally McBeal, as quoted in the March issue of Detour
Facilities need to identify not only what went wrong, but also all of the negative aftereffects (which are the damages facilities will seek from defendants in a potential lawsuit).
A 1989 review article that evaluated the methodology of seventy-six studies on the psychological aftereffects of abortion noted that both opponents and advocates of abortion could easily prove their case by picking and choosing from a wide range of contradictory evidence.
To add nuance to the simplicity that this model might suggest, Bellamy focuses on the processes of condensation by which the epic tries to appropriate romance - not simply an "imperialist" appropriation but one which produces "a generic edge by means of which the aftereffects of a romance unconscious leave their repressed, but nonetheless observable, traces" (32).