Sheep don't forget a face

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

The human brain has evolved specialized neural mechanisms for visual recognition of faces, which afford us a remarkable ability to discriminate between, remember and think about many hundreds of different individuals. Sheep also recognize and are attracted to individual sheep and humans by their faces, as they possess similar specialized neural systems in the temporal and frontal lobes for assisting in this important social task, including a greater involvement of the right brain hemisphere. Here we show that individual sheep can remember 50 other different sheep faces for over 2 years, and that the specialized neural circuits involved maintain selective encoding of individual sheep and human faces even after long periods of separation.

Related collections

Most cited references 9

Record: found
Abstract: found
Article: not found

Organization and functions of cells responsive to faces in the temporal cortex.

M Oram, Heikki J. Hietanen, Alan Benson … (1992)

Cells selectively responsive to the face have been found in several visual sub-areas of temporal cortex in the macaque brain. These include the lateral and ventral surfaces of inferior temporal cortex and the upper bank, lower bank and fundus of the superior temporal sulcus (STS). Cells in the different regions may contribute in different ways to the processing of the facial image. Within the upper bank of the STS different populations of cells are selective for different views of the face and head. These cells occur in functionally discrete patches (3-5 mm across) within the STS cortex. Studies of output connections from the STS also reveal a modular anatomical organization of repeating 3-5 mm patches connected to the parietal cortex, an area thought to be involved in spatial awareness and in the control of attention. The properties of some cells suggest a role in the discrimination of heads from other objects, and in the recognition of familiar individuals. The selectivity for view suggests that the neural operations underlying face or head recognition rely on parallel analyses of different characteristic views of the head, the outputs of these view-specific analyses being subsequently combined to support view-independent (object-centred) recognition. An alternative functional interpretation of the sensitivity to head view is that the cells enable an analysis of 'social attention', i.e. they signal where other individuals are directing their attention. A cell maximally responsive to the left profile thus provides a signal that the attention (of another individual) is directed to the observer's left. Such information is useful for analysing social interactions between other individuals.(ABSTRACT TRUNCATED AT 250 WORDS)

0 comments Cited 135 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Imagery neurons in the human brain.

G Kreiman, Eiko I Fried, Sabine Koch (2000)

Vivid visual images can be voluntarily generated in our minds in the absence of simultaneous visual input. While trying to count the number of flowers in Van Gogh's Sunflowers, understanding a description or recalling a path, subjects report forming an image in their "mind's eye". Whether this process is accomplished by the same neuronal mechanisms as visual perception has long been a matter of debate. Evidence from functional imaging, psychophysics, neurological studies and monkey electrophysiology suggests a common process, yet there are patients with deficits in one but not the other. Here we directly investigated the neuronal substrates of visual recall by recording from single neurons in the human medial temporal lobe while the subjects were asked to imagine previously viewed images. We found single neurons in the hippocampus, amygdala, entorhinal cortex and parahippocampal gyrus that selectively altered their firing rates depending on the stimulus the subjects were imagining. Of the neurons that fired selectively during both vision and imagery, the majority (88%) had identical selectivity. Our study reveals single neuron correlates of volitional visual imagery in humans and suggests a common substrate for the processing of incoming visual information and visual recall.

0 comments Cited 60 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Cells in temporal cortex of conscious sheep can respond preferentially to the sight of faces.

K Kendrick, B Baldwin (1987)

To investigate whether the temporal cortex of a nonprimate species contains cells responsive to the sight of faces, a study was made in conscious sheep of the responses of neurons in this brain region to the sight of faces. Of 561 cells from which responses were recorded, 40 responded preferentially to faces. Different categories of these cells were influenced by dominance (presumably indicated by the presence and size of horns), breed and familiarity, and threatening faces such as those of humans and dogs. These results demonstrate that cells that respond preferentially to faces are present in the temporal cortex of a nonprimate species, and that the responses of these cells are influenced by factors relevant to social interaction.