00:00Welcome to 2-Minute Neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less.
00:04In this installment, I will discuss directional terms in neuroscience.
00:08There are several terms that we use to indicate direction in neuroscience.
00:11Some are very straightforward.
00:13For example, superior always means towards the top of the head, inferior always means towards the feet.
00:18Likewise, anterior always refers to the front of the body or the brain,
00:22while posterior always refers to the back of the body or the brain.
00:26There are also some terms, however, like dorsal and ventral that change their meaning depending on whether we are referring
00:31to the brain or the spinal cord.
00:32When used for animals that move through the world horizontally, dorsal refers to the back and ventral refers to the
00:38abdominal region.
00:39With humans, the same usage applies when we are looking at the spinal cord.
00:43At the junction between the top of the brainstem and the diencephalon, however, the axis shifts due to the fact
00:49that humans walk upright.
00:50Above this level, dorsal refers to the superior portion of the brain, and ventral refers to the inferior portion.
00:57A similar situation occurs with the terms rostral and caudal.
01:00Rostral means towards the nose, and caudal means towards the tail.
01:03In animals that swim or walk on all fours, these orientations are consistent,
01:07but in humans, they shift at the brainstem diencephalon junction.
01:11At the level of the spinal cord, rostral points up towards the head, while caudal points down towards the end
01:16of the cord.
01:16In the brain, however, rostral points towards the anterior part of the brain, while caudal points towards the posterior part
01:22of the brain.
01:24The brain can also be examined on three different planes,
01:26and these planes are used to describe ways the brain is often sliced into sections for examination.
01:30A sagittal section is seen when a slice down the middle of the brain divides the brain into two separate
01:34halves.
01:36A horizontal or transverse section is made by slicing the brain perpendicular to the long axis of the body.
01:44A coronal or frontal section is seen when a slice is made parallel to the long axis of the body.
01:49When looking at the brain or spinal cord in any orientation,
01:52the parts of the brain that are closer to the midline are called medial,
01:55while those that are closer to the sides are called lateral.
01:57Rostral.
01:57overtral.
01:57You