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Brain structures

A

amygdala: means "almond", so-named because of its shape and size. The amygdala is part of the basal ganglia, and is situated in the temporal lobe. It has many connections with other parts of the brain, most particularly with the limbic system, for which reason it is considered part of the limbic system (although not part of the limbic lobe itself). The amygdala is critically involved in computing the emotional significance of events, and recent research indicates it is responsible for the influence of emotion on perception, through its connections with those brain regions that process sensory experiences, thus "allowing perception of emotionally significant events to occur despite inattention.” Rat studies also suggest that the amygdala, in tandem with the orbitofrontal cortex, is involved in the forming of new associations between cues and outcomes - in other words, it is the work of the amygdala to teach us what happens to us when we do something.
see amygdala news reports

angular gyrus: a gyrus located in the inferior parietal lobule, at the crossroads of areas specialized for processing touch, hearing and vision. Larger in hominids than other primates, it has been implicated in our understanding of metaphor.
Neural changes produced by learning to read revealed ; Meditation speeds the mind's return after distraction ; Brain region for understanding metaphors located

anterior cingulate: also known as area 24 of Brodmann-1905. The anterior cingulate is a defined area of the cerebral cortex including parts of both the cingulate gyrus and the frontal lobe.
see anterior cingulate news reports

anterior temporal cortex: part of the temporal cortex; believed to store facts about people and thought to be an essential part of the identifying process.
How the brain recognizes a face

B

basal ganglia: are large "knots" (ganglion means knot) of nerve cells deep in the cerebrum. They are thought to be involved in various aspects of motor behavior (Parkinson's disease, for example, is an affliction of the basal ganglia). Structures contained in the basal ganglia include the amygdala, globus pallidus, and striatum (containing the caudate nucleus and the putamen).
see basal ganglia news reports

brain stem: is the most primitive part of the brain, which also means it controls the most basic functions (such as breathing. It may be thought of as the stem connecting the spinal cord and the cerebral hemispheres. It includes the thalamus, hypothalamus, midbrain, medulla, and pons.
Early music training 'tunes' auditory system

Broca's region: is located in the frontal lobe, and, for most people, the left hemisphere (some left-handers have this area in the right hemisphere). Originally thought to be "the" speech center, it is now understood that a number of regions of the brain are involved in language behavior. More recently, Broca's area has been implicated in music processing, leading some researchers to suggest music may be processed as a language. Imaging studies have revealed that professional musicians trained at an early age have an increased volume of gray matter in Broca's area. Broca's area is part of a language and music processing network that includes Wernicke's area, the superior temporal sulcus, Heschl's gyrus, planum polare, planum temporale, and the anterior superior insular cortices.
see Music and language ; also Broca's area news reports

C

callosal isthmus: the narrowest part of the corpus callosum, at the posterior, where parts of the parietal cortex and superior temporal cortex are connected across the hemispheres
Processing speed component of intelligence is largely inherited

caudate nucleus: is located in the basal ganglia; with the putamen, it forms that part of the basal ganglia known as the striatum. also see left caudate
see caudate news reports

cerebellum: is the main structure in the hindbrain, situated at the base of the brain, at the top of the spinal cord. The cerebellum controls our balance and postural stability, and is involved in motor coordination - not, it appears, in the initial learning of motor skills, but in the performance and improvement of learned motor skills. Some regions of the cerebellum are especially vulnerable to the effects of chronic alcoholism. The hindbrain, although far from the frontal lobes, is connected to those regions, most especially through the pons and the thalamus. Recent rat studies have also suggested that the cerebellum may be involved in some way in remembering strong emotions, in particular, in the consolidation of long-term memories of fear. There is also growing evidence that the cerebellum might also be involved in processing speech and language.
see cerebellum news reports

cerebral cortex: the gray matter outer layer of the cerebrum. The newest part of the brain in evolutionary terms; responsible for primary sensory functions, motor coordination and control, and most particularly, the "higher-order" functions of language and thinking.
More on how memories are consolidated during sleep ; Brain enlargement may be characteristic of autism ; Human cerebellum and cortex age in very different ways ; Gene may be key to evolution of larger human brain

cerebrum: the largest structure of the brain; containing the cerebral cortex (the outer layer), which is made of gray matter, and an inner core composed of white matter (myelinated nerve fibers and gray basal ganglia); divided into a number of regions known as lobes.

cingulate gyrus: gyrus (fold) in the limbic lobe; implicated in self-reflective thought (thinking about yourself and your attributes).
Processing speed component of intelligence is largely inherited ; New brain region associated with face recognition

claustrum: a thin cell mass separating the putamen from the insula cortex; part of the basal ganglia.
see claustrum news reports

cornu ammonis: a substructure of the hippocampus, highly active during encoding (learning) of face-name pairs. (also see dentate gyrus and subiculum)
More details about how memories are formed in the hippocampus

corona radiata: sheet of white matter that is continuous with the internal capsule (they meet at the putamen)
Overweight and obese elderly have smaller brains ; Processing speed component of intelligence is largely inherited

corpus callosum: the main "bridge" between the left and right cerebral hemispheres; a broad bundle of myelinated fibers (white matter) carrying information from regions in one lobe to similarly placed regions in the opposing lobe. There are some 300 million fibers in the average corpus callosum. Cutting the corpus callosum prevents communication between the hemispheres (creating the well-known "split-brain" cases), and is used in severe cases of epilepsy.
Fitness counteracts cognitive decline from hormone-replacement therapy ; More light on a common developmental disorder ; Recognizing yourself is different from recognizing other people

cuneus: located in the medial occipital lobe; involved in visual processing -- it contains part of the primary visual striate cortex and extrastriate visual cortex
Common variation in gene linked to structural changes in the brain

D

dentate gyrus: a substructure of the hippocampus, highly active during encoding (learning) of face-name pairs. (also see cornu ammonis and subiculum)
see dentate gyrus news reports

dorsolateral prefrontal cortex: part of the prefrontal cortex, associated with tasks that require concentration, such as reading
see dorsolateral prefrontal cortex news reports

E

entorhinal cortex: part of the mediotemporal lobe; the main input to and output from the hippocampus. A vital part of the long-term memory store, and one of the first regions damaged in the early stages of Alzheimer's. See The rhinal cortex
Growth factor protects key brain cells in Alzheimer's models

extrastriate region: connected to the caudate nucleus and the putamen; parts may serve a visuospatial function, while other parts have been implicated in visual object-related processes.
see extrastriate news reports

F

forebrain: the brain develops, in utero, in three separate portions, reflecting evolutionary history: the hindbrain, the midbrain, and the forebrain. The forebrain develops into the cerebral cortex, the basal ganglia, the limbic system, the thalamus and hypothalamus.
Now definite? Memories are consolidated during sleep

fornix: a bundle of axons that projects from the hippocampus and loops around the thalamus.

frontal lobe: the frontal lobes (left and right) are situated at the "front" of the cortex, i.e. behind the forehead. They are the largest of the lobes in the cerebrum, and may be thought of as the "highest" part of our brain. The frontal lobes are critical for those faculties that humans regard as special to our species - reasoning, planning, attention, some aspects of language. Women have up to 15% more brain cell density in the frontal lobe, but with age, appear to shed cells more rapidly from this area than men. By old age, the density is similar for both sexes. The effect of this on performance is unknown. see also fronto-parietal network
see frontal lobe news reports

fronto-occipital fasciculus: a bundle of axons that have grown together, running alongside the caudate nucleus and connecting the frontal and occipital lobes (merging there into the corona radiate); sometimes referred to as the superior fronto-occipital fasciculus
Processing speed component of intelligence is largely inherited

fronto-parietal network: a growing body of evidence points to a network of connected regions in the adjacent frontal and parietal lobes, that have been implicated in higher-order processing such as attention, decision-making, and intelligence.
see fronto-parietal network news reports

fronto-polar region: is a substructure of the frontal lobes consisting of several gyri of similar morphology.
How sleep improves memory

fusiform gyrus: a gyrus in the temporal lobe. Part of a network of brain regions with the amygdala as well as the medial prefrontal cortex, the occipitofrontal cortex, and the superior temporal sulcus, which are involved in the processing of socially salient stimuli (important for social behavior). The fusiform gyrus is particularly implicated in face recognition. The right fusiform gyrus has been implicated in the processing of positive emotional contexts.
see fusiform gyrus news reports

G

Geschwind's territory: a newly discovered brain region, implicated in language. This area connects Broca's and Wernicke's areas via a region of the parietal lobe of the cortex, and may be important for the acquisition of language in childhood. The area is apparently the last area in the brain to mature, the completion of its maturation coinciding with the development of reading and writing skills.
Third language area in brain identified

gyrus: a fold or convolution in the cerebrum (compare sulcus)

H

Heschl's gyrus: the primary auditory cortex, located in the superior temporal gyrus, in the temporal lobe. Part of a language and music processing network that includes Broca's area, Wernicke's area, the superior temporal sulcus, planum polare, planum temporale, and the anterior superior insular cortices.
see Music and language, and Heschl's gyrus news reports

hindbrain:the brain develops, in utero, in three separate portions, reflecting evolutionary history: the hindbrain, the midbrain, and the forebrain. The hindbrain (the oldest part of the brain) develops into the cerebellum, the pons, and the medulla.
Study of alcoholics reveals connection between cerebellum and prefrontal cortex

hippocampus: means "sea horse", and is named for its shape. It is one of the oldest parts of the brain, and is buried deep inside, within the limbic lobe. The hippocampus is important for the forming, and perhaps long-term storage, of associative and episodic memories. Specifically, the hippocampus has been implicated in (among other things) the encoding of face-name associations, the retrieval of face-name associations, the encoding of events, the recall of personal memories in response to smells. It may also be involved in the processes by which memories are consolidated during sleep.
see hippocampus news reports

I

inferior frontal gyrus: a gyrus in the frontal lobe that is active in many different language tasks and plays a role in integrating brain regions. see also left inferior frontal gyrus
see inferior frontal gyrus news reports

inferior occipital gyrus: a gyrus in the occipital lobe that appears to be particularly sensitive to slight physical changes in faces.
How the brain recognizes a face

inferior parietal lobule: part of the parietal lobe; also known as the inferior parietal gyrus. A fold in the lower area of the parietal lobe. The area is sensitive to phonological demands and appears to be involved in reading. (also see left inferior parietal cortex)
see inferior parietal lobule news reports

inferior temporal gyrus: a fold in the lower area of the temporal lobe. The area is involved in object recognition.
Special training may help people with autism recognize faces

insular cortex: part of the paralimbic zone, it is critical for perception and modulation of sensory and autonomic data, including pain and visceral sensations. It's also involved in speech.
Sleep deprivation can threaten competent decision-making ; Neurons targeted by dementing illness may have evolved for complex social cognition ; How sleep improves memory

internal capsule: a collection of axons connecting the cerebral cortex and the brain stem
Processing speed component of intelligence is largely inherited

intraparietal sulcus: a sulcus in the inferior parietal lobule that is implicated in language processing, in particular spelling.Also recently implicated in skill learning.
Watching with intent to repeat ignites key learning area of brain ; Brain networks change according to cognitive task

L

lateral temporal cortex: a part of the temporal lobe that is implicated in language processing, in particular rhyme.
Brain networks change according to cognitive task

lateral ventricle: part of a series of interconnected cavities containing cerebrospinal fluid in the core of the brain
Wnt signaling vital for adult neurogenesis

left caudate: the left hemisphere caudate has been implicated in the control of language switching in the brains of bilingual people.
How does the bilingual brain distinguish between languages?

left inferior frontal gyrus: the part of the inferior frontal cortex in the left hemisphere; implicated in preventing memory interference
Having right timing 'connections' in brain is key to overcoming dyslexia; More insight into why we forget

left inferior parietal cortex: the part of the inferior parietal cortex in the left hemisphere; active during both procedural and declarative learning; active during encoding of unfamiliar faces. (see left prefrontal cortex and right putamen)
see inferior parietal cortex news reports

left prefrontal cortex: part of the prefrontal cortex; active during both procedural and declarative learning; active during encoding of unfamiliar faces. (see left inferior parietal cortex and right putamen)
see left prefrontal cortex news reports

limbic lobe: a lobe that lies deep within the cerebrum - a broad collar of cortex fringing the corpus callosum (limbic means "border"). The limbic lobe includes the hippocampus, cingulate gyrus, dentate gyrus, and the parahippocampal gyrus.
Deep brain stimulation may improve memory ; Alcohol's damaging effects on adolescent brain function

lobes: the cerebrum is highly convoluted - it is this deep and numerous folding that vastly increases the cortical area of the human brain. The deepest fissures provide somewhat arbitrary boundaries for the mapping of the brain. Following these guidelines, the cerebrum is divided into five lobes: the frontal, temporal, parietal, occipital and limbic lobes.

M

mammillary bodies: these structures receive projections from the hippocampus via the fornix, project heavily to the anterior thalamus, and have been implicated in conditions with memory deficiencies, such as Korsakoff's syndrome.
Memory loss linked to sleep apnea

medial prefrontal cortex: part of the prefrontal cortex close to the midline, implicated in social memory.
see medial prefrontal cortex news reports

mediotemporal lobe (MTL): includes the hippocampus, the amygdala, and the entorhinal and perirhinal cortices. Although given this name, the idea that this is an integrated memory system with a common function has recently been questioned. It is observed that the various components evolved at different points. Nevertheless, we may say that the MTL appears to be involved in declarative learning (facts and events), being particularly important during initial learning. There is some evidence that long-term consolidation of memories is guided by the MTL, in particular by the entorhinal cortex (which is damaged in the early stages of Alzheimer’s disease). Moreover, a recent study showed that progressive atrophy in the medial temporal lobe was the most significant predictor of cognitive decline in seniors.
see mediotemporal lobe news reports ; The role of consolidation in sleep

mesolimbic region: links the ventral tegmentum in the midbrain to the nucleus accumbens. It is one of the four major pathways for the neurotransmitter dopamine, and is involved in pleasure, reward, and motivation.
Why motivation helps memory

midbrain: the brain develops, in utero, in three separate portions, reflecting evolutionary history: the hindbrain, the midbrain, and the forebrain. The midbrain includes the tectum and the tegmentum, which lie on either side of the cerebral aqueduct, a reservoir in the midbrain for cerebrospinal fluid. The midbrain is involved in automatic reflexes associated with the visual and auditory systems, and more recently has been implicated in assessing reward values.
Novelty aids learning

middle frontal gyrus: a gyrus in the middle part of the frontal lobe.
see middle frontal gyrus news reports

N

neocortex: the "new" part of the cortex - the most recent and complex part of the brain. The frontal, temporal, parietal and occipital lobes are all part of the neocortex.
Long-term storage of autobiographical memories ; Brain circuit crucial for memory consolidation identified ; More support for social skill theory of brain evolution

nucleus accumbens: located between the caudate and the putamen; critically involved in the 'reward circuit'.
Sleep deprivation can threaten competent decision-making

O

occipital lobe: one of the lobes of the cerebrum, situated at the back of the skull, and above the hindbrain. It borders with the parietal lobe (from which it is not clearly demarcated) and the temporal lobe. The occipital lobe contains the primary visual cortex, where visual information is processed.
Neural changes produced by learning to read revealed ; Specific brain region for reading

operculum: is located in the inferior frontal gyrus, and partly overlaps with Broca's area. It's recently been implicated as one of the structures in the brain that coordinates the activities of other brain regions.
Master planners in brain may coordinate other areas' roles in cognitive tasks

orbitofrontal cortex: a part of the frontal lobe. Traditionally thought to be involved in "personality traits", such as social adjustment and the control of mood, drive and responsibility, and more recently implicated in drug addiction. Recent rat studies have found evidence that changing nerve cell firing patterns in the orbitofrontal cortex are involved in the learned of associations, through a connection with the amygdala.
see orbitofrontal cortex news reports

P

paracingulate cortex: part of the area extending from the anterior cingulate to the anterior frontal pole. Implicated in self-reflection, person perception and in making inferences about others' thoughts.
Autism's social struggles due to disrupted communication networks in brain

parahippocampal region: is located in the limbic lobe. Recent research has found neurons here that are responsive to landmarks.
The role of consolidation in sleep
see parahippocampal region news reports

paralimbic zone: an "uninterrupted girdle surrounding the medial and basal aspects of the cerebral hemispheres" containing the insula cortex, the temporal pole, the cingulate cortex, the parahippocampal cortices, and the orbitofrontal cortex.

parietal lobe: one of the lobes of the cerebrum, situated at the top, behind the frontal lobe. The primary sensory area is located in the parietal lobe - this is where nerve impulses carrying sensations of pain, temperature, touch, and pressure come. Areas in the parietal lobe are also involved in spatial orientation, speech and language development, and attention. see also fronto-parietal network; see parietal lobe news reports

parietotemporal region: the region where the parietal and temporal lobes meet. The area has been implicated in dyslexia.
Autism's social struggles due to disrupted communication networks in brain ; Remedial instruction can close gap between good, poor readers

pars triangularis: part of Broca's area, in the left inferior frontal gyrus

Common variation in gene linked to structural changes in the brain

perirhinal cortex: part of the medial temporal lobe
Encoding isn’t solely in the hippocampus ; How the brain creates false memories

piriform cortex: piriform / pyriform means pear-shaped. It is a composite substructure that includes the lateral olfactory stria, one of three divisions of the olfactory tract. The olfactory system is the only sensory system that goes directly to the cerebral cortex without first synapsing in the thalamus.
Confirmation that a memory code is held in many different regions

planum polare: part of the superior temporal gyrus, in the temporal lobe; part of the cortical network involved in language and music processing.
Music and language

planum temporale: part of the superior temporal gyrus, in the temporal lobe. The planum temporal is part of the cortical network involved in language and music processing, and is generally larger in the left hemisphere than the right.
Music and language ; see planum temporale news reports

pons: short for pons varolii; a "bridge" (pons is Latin for bridge) of nerve fibers connecting the cerebellum and the medulla oblongata with other regions of the brain, most particularly with the frontal lobe.
Study of alcoholics reveals connection between cerebellum and prefrontal cortex

posterior parietal cortex: the rear part of the parietal lobe (thus adjacent to the occipital lobe). Associated in humans with a variety of complex behaviors such as the appreciation of objects and their qualities, facial recognition and social communication. Most recently implicated as the limiting factor in the storage capacity of our visual working memory.
see posterior parietal news reports

precuneus: part of the medial section of the posterior parietal cortex
How false memories are formed

prefrontal cortex: is the area of the brain at the very front of the frontal lobes. It is involved in "executive functions", such as working memory, decision-making, planning and judgment. Prefrontal regions appear to be particularly sensitive to the effects of aging. It is thought that the reduced ability to recall the context of memories that occurs with advancing age, is evidence that the prefrontal cortex is also critical for context processing - a process involved in many cognitive functions. A recent study has also revealed that emotional stimuli and attentional functions are integrated in a specific part of the prefrontal cortex - the anterior cingulate (located between the right and left halves). See also medial prefrontal cortex and left prefrontal cortex
see prefrontal cortex news reports

premotor cortex: is part of the motor cortex, located in the frontal lobe. It is adjacent to the primary motor area. It is located primarily in the precentral gyrus and caudal portions of the superior frontal gyrus and the middle frontal gyrus.
see premotor cortex news reports

presupplementary motor area: found in the medial frontal lobe, specifically in the anterior part of the medial premotor cortex, it receives input from the basal ganglia and cerebellum, and is implicated in visuo-motor associations.
From 12 years onward you learn differently

primary auditory cortex: see Heschl's gyrus.

primary motor cortex: is in the precentral gyrus in the frontal lobe. It is one of three parts of the motor cortex, the others being the premotor cortex, and the supplementary motor cortex.
see primary motor cortex news reports

primary visual striate cortex: is located largely on the medial surface of the occipital lobe. This is where visual images, having been dissected by the retina, begin to be reassembled for further processing (in adjacent areas).
Where visual short-term memory occurs ; More complex brain may have pre-dated Homo genus

putamen: part of the basal ganglia; active during both procedural and declarative learning. (see left prefrontal cortex and left inferior parietal cortex)
see putamen news reports

R

right intraparietal sulcus: a sulcus in the right parietal lobe, implicated in dyscalculia
Right parietal lobe implicated in dyscalculia

right parietal lobe: part of the parietal cortex, implicated in numerical processing.

S

somatosensory neocortex: or primary somesthetic area / primary somatic sensory area. It is located in the parietal lobe, and deals with information from the various "touch" receptors, such as temperature, pressure, limb position, movement, pain, etc. It has been implicated in the processes by which memories (or some type of them) are consolidated during sleep.
What we perceive is not what we sense ; Another step in understanding how sleep affects memory

striatum: includes the caudate nucleus and the putamen; part of the basal ganglia. Implicated in habit learning.
see striatum news reports

subgenual area 25: also known as area 25 of Brodmann-1905; a subdivision of the cingulate region
Fitness counteracts cognitive decline from hormone-replacement therapy

subiculum: a substructure of the hippocampus, active during the retrieval of newly-learned face-name associations (but less so as retrieval became more practiced).(also see dentate gyrus and cornu ammonis)
Hippocampus and subiculum both critical for short-term memory ; More details about how memories are formed in the hippocampus

substantia nigra: a group of cells in the midbrain that use dopamine, and connect to the striatum
Novelty aids learning

subventricular zone: is located in the walls of the lateral ventricle. It is one of two regions in the adult brain in which new brain cells are created. New neurons created in this region travel to the olfactory bulb.
New brain cells are essential for learning

sulcus: a cleft or fissure in the cerebrum (compare gyrus)

superior parietal cortex: a region in the upper part of the parietal lobe.
From 12 years onward you learn differently ; Exercise improves attention and decision-making among seniors ; Training improves working memory capacity

superior temporal gyrus: a gyrus in the upper part of the temporal lobe. Contains the primary auditory cortex. The anterior part of this region has been implicated in generating the aha! experience of insight.
Brain region involved in insight localized

superior temporal sulcus: a sulcus in the upper part of the temporal lobe.

supplementary motor area: is part of the motor cortex, found in the medial frontal lobe. The other parts are the primary motor cortex and the premotor cortex. Like the presupplementary motor area, it receives input from the basal ganglia and cerebellum. It has been implicated in the initiation and control of voluntary movements.

T

temporal lobe: one of the lobes of the cerebrum, situated below the frontal and parietal lobes, and above the hindbrain. The temporal lobe is primarily concerned with sensory experience - specifically, with hearing, and with the integration of information from multiple senses. Part of the temporal lobe also plays a role in memory processing. Patients with damaged temporal lobes appear to have impaired lexical retrieval of names of living things.
see temporal lobe news reports

temporal pole: is at the anterior tip of the temporal lobe. It is part of the paralimbic zone and is involved in the retrieval of episodic and semantic memory, and the processing of familiar and emotional stimuli such as faces.
How sleep improves memory

temporoammonic (TA) projection: a circuit in the brain directly linking the CA1 region of the hippocampus and the neocortex. Apparently crucial in converting short-term memories into long-term memories.
Brain circuit crucial for memory consolidation identified

thalamus: means "inner chamber", and accordingly is located deep within the cerebrum. It is an egg-shaped structure lying at the very top of the brain stem, above the hypothalamus. The thalamus relays all information received from the senses (except smell) to the various processing centers in the cerebral cortex. Recent research also suggests that the thalamus regulates the electrical rhythms that parts of the brain use to communicate with each other. It has been speculated that tips of the tongue experiences (when only part of a memory is recalled) may occur when the rhythms don't synchronize with the regions properly - which would put these memory failures at the door of the thalamus. The thalamus also seems to be involved in memory consolidation processes that occur during sleep.
see thalamus news reports

V

ventromedial prefrontal cortex: the rear part of the prefrontal cortex, including the cortex on top of the orbits of both eyes and the inside part of the frontal lobes.
see ventromedial prefrontal cortex news reports

W

Wernicke's area: is one of the primary auditory areas. The structure includes part of the supramarginal gyrus, the angular gyrus, the superior temporal gyrus and the middle temporal gyrus. It is involved in language comprehension - specifically, allows you to understand the meaning of spoken words.
see Wernicke's area news reports

Other resources on the Web:

if you're into neuroimaging, you can leaf through a "brain atlas" at http://www.med.harvard.edu/AANLIB/home.html

at a much more accessible level (and rather more fun), PBS have a "3-dimensional" tour of the brain at http://www.pbs.org/wnet/brain/3d/index.html (you do need Shockwave to view this)

you can also look up names of brain structures at http://braininfo.rprc.washington.edu/mainmenu.html

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