Barognosis, or baresthesia, is the ability

Skill

A skill is the learned capacity to carry out pre-determined results often with the minimum outlay of time, energy, or both. Skills can often be divided into domain-general and domain-specific skills...

 of evaluating the weight of objects, or to differentiate objects of different weights by looking at them. It is the opposite of baragnosis

Baragnosis

Baragnosis is an inability to accurately judge weight differences. It is the opposite of barognosis, the ability to accurately judge weight differences. It is usually a result of damage to the primary somatosensory cortex. This damage is commonly caused by a lesion or a subdural hemorrhage of the...

, the inability of evaluating the weight of objects. This sensory information is transmitted by the posterior column-medial lemniscus pathway

Posterior column-medial lemniscus pathway

The posterior column-medial lemniscus pathway is the sensory pathway responsible for transmitting fine touch, vibration and conscious proprioceptive information from the body to the cerebral cortex; as well as tactile pressure, barognosis, graphesthesia, stereognosis, recognition...

 of the spinal cord, which also carries the sensations of fine touch

Fine touch

Fine touch, , is a sensory modality which allows a subject to sense and localise touch. The form of touch where localisation is not possible is known as crude touch....

, stereognosis

Stereognosis

Stereognosis is the ability to perceive and recognize the form of an object using cues from texture, size, spatial properties, and temperature...

, tactile pressure, graphesthesia

Graphesthesia

Graphesthesia is the ability to recognize writing on the skin purely by the sensation of touch. Its name derives from Greek graphē and aisthēsis...

, texture recognition, kinesthesia, two-point discrimination

Two-point discrimination

Two-point discrimination is the ability to discern that two nearby objects touching the skin are truly two distinct points, not one. It is often tested with two sharp points during a neurological examination and reflects how finely innervated an area of skin is....

, proprioception

Proprioception

Proprioception , from Latin proprius, meaning "one's own" and perception, is the sense of the relative position of neighbouring parts of the body and strength of effort being employed in movement...

, and vibration

Vibration

Vibration refers to mechanical oscillations about an equilibrium point. The oscillations may be periodic such as the motion of a pendulum or random such as the movement of a tire on a gravel road.Vibration is occasionally "desirable"...

.

To test for intact barognosis, a set of small objects with the same size and shape, but of graduated weight is used. A series of different weights can be placed one at a time in the same hand, and the patient is asked to identify the comparative weight of the objects, i.e. by saying if the object is "heavier" or "lighter". Other methods for testing include different weights being placed in each hand simultaneously, or having the patient pick up each weight using a fingertip grip.