Lukaszewska I, Markowska A, Dławichowska E
Acta Neurobiol Exp (Wars). 1988;48(4):137-44.
Our previous findings indicated that hippocampal lesions (H) or scopolamine' injections (Sc) affected stimulus information acquired by distant observation of the white-black T-maze arms (the passive test), but left the information intact when it was gained by T-maze exploration (the active test). Because this difference might reflect the attentional deficit in H or Sc rats, in the present experiment we attempted to investigate the effect of lowered distinctiveness of cues (dark grey vs black T-maze arms) on the performance of rats in the active test. A total of 75 rats were assigned to four groups: (i) damaged in the dorsal hippocampus (H); (ii) sham operated (C); (iii) scopolamine (Sc) injected (1.0 mg/kg i. p.) and (iv) saline injected (NaCL). Each group showed a significant preponderance of choices of the arm which was changed in brightness between the two consecutive trials, separated by 1 min break. The groups did not differ markedly among themselves in the percentage of changed arm choices (H group, 85 percent; C, 74 percent; Sc -72 percent; NaCL, 72 percent). This result indicates that H or Sc rats are able to perceive a slight difference of brightness and to retain it over a period of 1 min. Therefore, the different performance of H as well as Sc rats in the passive and active test, observed previously, cannot be accounted for by the attentional deficit hypothesis.
我们之前的研究结果表明，海马损伤（H）或注射东莨菪碱（Sc）会影响通过远距离观察黑白T迷宫臂获取的刺激信息（被动测试），但当通过T迷宫探索获取信息时（主动测试），该信息保持完整。由于这种差异可能反映了H组或Sc组大鼠的注意力缺陷，在本实验中，我们试图研究降低线索的差异性（深灰色与黑色T迷宫臂）对大鼠在主动测试中表现的影响。总共75只大鼠被分为四组：（i）背侧海马损伤组（H）；（ii）假手术组（C）；（iii）注射东莨菪碱组（Sc，腹腔注射1.0 mg/kg）；（iv）注射生理盐水组（NaCl）。每组在连续两次试验（间隔1分钟休息）之间亮度发生变化的臂的选择上都表现出显著的偏好。各组之间在选择亮度变化臂的百分比上没有明显差异（H组，85%；C组，74%；Sc组，72%；NaCl组，72%）。这一结果表明，H组或Sc组大鼠能够感知亮度的细微差异并在1分钟内保持这种差异。因此，先前观察到的H组和Sc组大鼠在被动测试和主动测试中的不同表现不能用注意力缺陷假说来解释。
