Table 1.

Summary of the parameters and morphological appearance of the BDA injections in the three cases M, V and J. Values are given in μm. Size of the glass capillary was measured after the injection. Tip diameter represents the inner or outer diameter of the glass capillary used for the BDA injection. Outer diameter was measured if inner diameter was not visible due to minor blood infusion. Therefore, in cases V and J the approximate inner diameter is given in parenthesis. Injection depth was measured from the pial surface by a micromanipulator. Core diameter was measured in the section of the series where it exhibited the largest extent. Core depth: approximate depth of the largest core diameter in the section series. Difference between injection and core depth could result from pulsation and swelling of the brain during the injection. Core layer: approximate cortical depth where the core of the injection was most pronounced in the series of sections. In case V, where the core could not be unequivocally identified (for explanation see the text), the values were derived by measuring the highest density region of diffuse labeling around the electrode track. Track length: the approximate maximum depth where the electrode track could be recognized in the section series. While the electrode track was easy to follow in case V, it was hardly visible in cases M and J.

	Tip diameter	Injection depth	Core diameter	Core depth	Core layer	Track length
M	12 (inner)	350	260	260	260	520
V	30 (outer) (~20 inner)	350	380	390	390	520
J	25 (outer) (~15-17 inner)	350	330	390	260-390	520