Temporal lobe
Encyclopedia
The temporal lobe is a region of the cerebral cortex
that is located beneath the Sylvian fissure on both cerebral hemisphere
s of the mammal
ian brain
.
The temporal lobe is involved in auditory
perception
and is home to the primary auditory cortex
. It is also important for the processing of semantics
in both speech and vision
. The temporal lobe contains the hippocampus
and plays a key role in the formation of long-term memory
.
The superior temporal gyrus
includes an area (within the Sylvian fissure) where auditory signals from the cochlea
(relayed via several subcortical nuclei) first reach the cerebral cortex
. This part of the cortex (primary auditory cortex
) is involved in hearing. Adjacent areas in the superior, posterior and lateral parts of the temporal lobes are involved in high-level auditory processing. In humans this includes speech, for which the left temporal lobe in particular seems to be specialized. Wernicke's area
, which spans the region between temporal and parietal lobes, plays a key role (in tandem with Broca's area
, which is in the frontal lobe
). The functions of the left temporal lobe are not limited to low-level perception but extend to comprehension, naming, verbal memory
and other language functions.
The underside (ventral) part of the temporal cortices appear to be involved in high-level visual processing of complex stimuli such as faces
(fusiform gyrus
) and scenes (parahippocampal gyrus
). Anterior parts of this ventral stream for visual processing
are involved in object perception and recognition.
The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemisphere
s) are thought to be involved in episodic
/declarative memory
. Deep inside the medial temporal lobes lie the hippocampi
, which are essential for memory function - particularly the transference from short to long term memory and control of spatial memory and behavior. Damage to this area typically results in anterograde amnesia
.
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
that is located beneath the Sylvian fissure on both cerebral hemisphere
Cerebral hemisphere
A cerebral hemisphere is one of the two regions of the eutherian brain that are delineated by the median plane, . The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres has an outer layer of grey matter called the cerebral cortex that is...
s of the mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
ian brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
.
The temporal lobe is involved in auditory
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
perception
Perception
Perception is the process of attaining awareness or understanding of the environment by organizing and interpreting sensory information. All perception involves signals in the nervous system, which in turn result from physical stimulation of the sense organs...
and is home to the primary auditory cortex
Primary auditory cortex
The primary auditory cortex is the region of the brain that is responsible for the processing of auditory information. Corresponding roughly with Brodmann areas 41 and 42, it is located on the temporal lobe, and performs the basics of hearing—pitch and volume...
. It is also important for the processing of semantics
Semantics
Semantics is the study of meaning. It focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for, their denotata....
in both speech and vision
Visual perception
Visual perception is the ability to interpret information and surroundings from the effects of visible light reaching the eye. The resulting perception is also known as eyesight, sight, or vision...
. The temporal lobe contains the hippocampus
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
and plays a key role in the formation of long-term memory
Long-term memory
Long-term memory is memory in which associations among items are stored, as part of the theory of a dual-store memory model. According to the theory, long term memory differs structurally and functionally from working memory or short-term memory, which ostensibly stores items for only around 20–30...
.
The superior temporal gyrus
Superior temporal gyrus
The superior temporal gyrus is one of three gyri in the temporal lobe of the human brain, which is located laterally to the head, situated somewhat above the external ear.The superior temporal gyrus is bounded by:* the lateral sulcus above;...
includes an area (within the Sylvian fissure) where auditory signals from the cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
(relayed via several subcortical nuclei) first reach the cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
. This part of the cortex (primary auditory cortex
Primary auditory cortex
The primary auditory cortex is the region of the brain that is responsible for the processing of auditory information. Corresponding roughly with Brodmann areas 41 and 42, it is located on the temporal lobe, and performs the basics of hearing—pitch and volume...
) is involved in hearing. Adjacent areas in the superior, posterior and lateral parts of the temporal lobes are involved in high-level auditory processing. In humans this includes speech, for which the left temporal lobe in particular seems to be specialized. Wernicke's area
Wernicke's area
Wernicke's area is one of the two parts of the cerebral cortex linked since the late nineteenth century to speech . It is involved in the understanding of written and spoken language...
, which spans the region between temporal and parietal lobes, plays a key role (in tandem with Broca's area
Broca's area
Broca's area is a region of the hominid brain with functions linked to speech production.The production of language has been linked to the Broca’s area since Pierre Paul Broca reported impairments in two patients. They had lost the ability to speak after injury to the posterior inferior frontal...
, which is in the frontal lobe
Frontal lobe
The frontal lobe is an area in the brain of humans and other mammals, located at the front of each cerebral hemisphere and positioned anterior to the parietal lobe and superior and anterior to the temporal lobes...
). The functions of the left temporal lobe are not limited to low-level perception but extend to comprehension, naming, verbal memory
Verbal memory
Verbal memory is a term used in Cognitive Psychology that refers to memory of words and other abstractions involving language.-Verbal Encoding:Verbal Encoding refers to the interpretation of verbal stimuli...
and other language functions.
The underside (ventral) part of the temporal cortices appear to be involved in high-level visual processing of complex stimuli such as faces
Face perception
Face perception is the process by which the brain and mind understand and interpret the face, particularly the human face.The human face's proportions and expressions are important to identify origin, emotional tendencies, health qualities, and some social information. From birth, faces are...
(fusiform gyrus
Fusiform gyrus
The fusiform gyrus is part of the temporal lobe in Brodmann Area 37. It is also known as the occipitotemporal gyrus. Other sources have the fusiform gyrus above the occipitotemporal gyrus and underneath the parahippocampal gyrus....
) and scenes (parahippocampal gyrus
Parahippocampal gyrus
The parahippocampal gyrus is a grey matter cortical region of the brain that surrounds the hippocampus. This region plays an important role in memory encoding and retrieval....
). Anterior parts of this ventral stream for visual processing
Visual processing
Visual processing is the sequence of steps that information takes as it flows from visual sensors to cognitive processing. The sensors may be zoological eyes or they may be cameras or sensor arrays that sense various portions of the electromagnetic spectrum....
are involved in object perception and recognition.
The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemisphere
Cerebral hemisphere
A cerebral hemisphere is one of the two regions of the eutherian brain that are delineated by the median plane, . The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres has an outer layer of grey matter called the cerebral cortex that is...
s) are thought to be involved in episodic
Episodic memory
Episodic memory is the memory of autobiographical events that can be explicitly stated. Semantic and episodic memory together make up the category of declarative memory, which is one of the two major divisions in memory...
/declarative memory
Declarative memory
Declarative memory is one of two types of long term human memory. It refers to memories which can be consciously recalled such as facts and knowledge. Its counterpart is known as non-declarative or Procedural memory, which refers to unconscious memories such as skills...
. Deep inside the medial temporal lobes lie the hippocampi
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
, which are essential for memory function - particularly the transference from short to long term memory and control of spatial memory and behavior. Damage to this area typically results in anterograde amnesia
Anterograde amnesia
Anterograde amnesia is a loss of the ability to create new memories after the event that caused the amnesia, leading to a partial or complete inability to recall the recent past, while long-term memories from before the event remain intact. This is in contrast to retrograde amnesia, where memories...
.