REFERENCES
- Bobis , J. , Sweller , J. and Cooper , M. 1994 . Demands imposed by primary school students by geometric models . Contemporary Educational Psychology , 19 : 108 – 117 .
- Carpenter , P.A. and Just , M.A. 1986 . “ Spatial ability: an information processing approach to psycho‐metrics ” . In Advances in the Psychology of Human Intelligence , Edited by: Sternberg , R. J. Vol. 3 , 221 – 253 . New Jersey : LEA .
- Chandler , P. and Sweller , J. 1992 . Split attention effects as a factor in the design of instruction . British Journal of Educational Psychology , 62 : 233 – 246 .
- Cooper , L A. 1988 . “ The role of spatial representations in complex problem solving ” . In Cognition and Representation , Edited by: Schiffer , S. and Steele , S. 53 – 86 . Boulder, Colorado : Westview Press .
- Eysenck , M.W. and KEANE , M.T. 1995 . Cognitive Psychology: a students handbook , Erlbaum, , UK : Taylor & Francis .
- Halford , G. 1993 . Children's Understanding: development of mental models , New Jersey : LEA .
- Just , M.A. and Carpenter , P.A. 1985 . Cognitive coordinate systems: accounts of mental rotation and individual differences in spatial ability . Psychological Review , 92 : 137 – 171 .
- Keenan , J.M. and Moore , R.E. 1979 . Memory for images of concealed objects: a re‐examination of Neisser and Kerr . Journal of Experimental Psychology: Human Memory and Learning , 5 : 374 – 385 .
- Kosslyn , S.M. 1980 . Image and Mind , Cambridge, MA : Harvard University Press .
- Kosslyn , S.M. 1981 . The medium and the message in mental imagery: a theory . Psychological Review , 88 : 46 – 66 .
- Kosslyn , S.M. and Pomerants , J.R. 1997 . Imagery, proposition, and the form of internal representation . Cognitive Psychology , 9 : 52 – 76 .
- Marcus , N. , Cooper , M. and Sweller , J. 1996 . Understanding instruction . Journal Of Educational Psychology , 88 (1) : 49 – 63 .
- Patel , V.L. , Groen , G.J. and Arocha , J.F. 1990 . Medical expertise as a function of task difficulty . Memory and Cognition , 18 (4) : 394 – 406 .
- Pillay , H. 1994 . Cognitive load and mental rotation: structuring orthographic projection for learning and problem solving . Instructional Science , 22 (2) : 91 – 113 .
- Riding , R.J. and Sadler‐Smith , E. 1992 . Type of instructional material, cognitive style and learning performance . Educational Studies , 18 : 323 – 340 .
- Sweller , J. 1989 . Cognitive technology: some procedures for facilitating learning and problem solving in mathematics and science . Journal of Educational Psychology , 81 (4) : 457 – 466 .
- Sweller , J. and Chandler , P. 1994 . Why some material is difficult to learn . Cognition and Instruction , 12 : 185 – 223 .
- SPSS‐X Inc. 1990 . SPSS‐X Reference Guide: SPSS Statistical Data Analysis , Chicago : SPSS Inc. .