Psy3241 - User contributions [en]

Ptito et al. (2005)

2008-04-25T04:44:10Z

Cwhitehead:

[[Category:Plasticity Symposium]]

'''Cross-Modal Plasticity Revealed by Electrotactile Stimulation of the Tongue in the Congenitally Blind (Ptito et al., 2005)'''

The experimenters in this study used PET to study cross-modal plasticity in the congenitally blind, using electrotactile stimulation of the tongue.

== Participants ==
Participants included 6 blind and 5 sighted blind-folded controls.

== Training ==
Participants were trained to use their tongue in a Snellen orientation detection. The tongue was used for this study because of it's high sensitivity and good acessiblity. They were scanned before and after training.

== Results ==
Before training, no significant changes in regional cerebral blood flow (rCBF) was observed in the occipital cortex of either group. After practice for the blind, however, activity in the occipital cortex increased. This increase in activity was not observed in the sighted participants yet there was an increase in somatosensory activity, providing evidence for training-induced plasticity in the congenitally blind.

An inter-regional correlation analysis showed that task-related rCBF changes in the left posterior parietal cortex were positively correlated with rCBF changes in the occipital area of the trained blind participants.

== Conclusion ==
This data revealed that cross-modal plasticity in the blind develops rapidly and that the occipital cortex is part of a functional neural network for tactile discrimination in conjunction with the posterior parietal cortex. Data further showed that the tongue can act as a portal to convey somatosensory information to visual cortex and that with no visual input the occipital lobe assumes the role of tactile discrimination. This modification of the brain is an example of plasticity.

Ptito et al. (2005)

2008-04-25T04:40:19Z

Cwhitehead:

[[Category:Plasticity Symposium]]

'''Cross-Modal Plasticity Revealed by Electrotactile Stimulation of the Tongue in the Congenitally Blind (Ptito et al., 2005)'''

The experimenters in this study used PET to study cross-modal plasticity in the congenitally blind, using electrotactile stimulation of the tongue.

== Participants ==
Participants included 6 blind and 5 sighted blind-folded controls.

== Training ==
Participants were trained to use their tongue in a Snellen orientation detection task. They were scanned before and after training.

== Results ==
Before training, no significant changes in regional cerebral blood flow (rCBF) was observed in the occipital cortex of either group. After practice for the blind, however, activity in the occipital cortex increased. This increase in activity was not observed in the sighted participants yet there was an increase in somatosensory activity, providing evidence for training-induced plasticity in the congenitally blind.

An inter-regional correlation analysis showed that task-related rCBF changes in the left posterior parietal cortex were positively correlated with rCBF changes in the occipital area of the trained blind participants.

== Conclusion ==
This data revealed that cross-modal plasticity in the blind develops rapidly and that the occipital cortex is part of a functional neural network for tactile discrimination in conjunction with the posterior parietal cortex. Data further showed that the tongue can act as a portal to convey somatosensory information to visual cortex and that with no visual input the occipital lobe assumes the role of tactile discrimination. This modification of the brain is an example of plasticity.

Ptito et al. (2005)

2008-04-25T04:38:20Z

Cwhitehead:

[[Category:Plasticity Symposium]]

'''Cross-Modal Plasticity Revealed by Electrotactile Stimulation of the Tongue in the Congenitally Blind (Ptito et al., 2005)'''

The experimenters in this study used PET to study cross-modal plasticity in the congenitally blind, using electrotactile stimulation of the tongue.

== Participants ==
Participants included 6 blind and 5 sighted blind-folded controls.

== Training ==
Participants were trained to use their tongue in a Snellen orientation detection task. They were scanned before and after training.

== Results ==
Before training, no significant changes in regional cerebral blood flow (rCBF) was observed in the occipital cortex of either group. After practice for the blind, however, activity in the occipital cortex increased. This increase in activity was not observed in the sighted participants, providing evidence for training-induced plasticity in the congenitally blind.

An inter-regional correlation analysis showed that task-related rCBF changes in the left posterior parietal cortex were positively correlated with rCBF changes in the occipital area of the trained blind participants.

== Conclusion ==
This data revealed that cross-modal plasticity in the blind develops rapidly and that the occipital cortex is part of a functional neural network for tactile discrimination in conjunction with the posterior parietal cortex. Data further showed that the tongue can act as a portal to convey somatosensory information to visual cortex and that with no visual input the occipital lobe assumes the role of tactile discrimination. This modification of the brain is an example of plasticity.

Wada test

2008-04-25T04:34:58Z

Cwhitehead:

[[Category:Neuropsychological methods]]

The Wada test involves administering a fast acting barbiturate to one hemisphere at a time. The barbiturate is adminstered through the left or right carotid artery.

Carl Wernicke

2008-04-25T04:31:34Z

Cwhitehead:

[[image:Wernicke.jpg|200px|thumb|Carl Wernicke]]

Carl Wernicke was a German psychologist and neuropathologist born on May 15, 1848 in Upper Silesia. He is most known for his work with neurological disorders associated with language. He is often associated with his discovery of [[Wernicke's area]], an area bordering the posterior temporal lobe which is known to be involved in speech comprehension. While examining a stroke patient of his postmortem, he noticed a lesion in the area now known as Wernicke's area. While alive, the patient was able to speak, but could not understand speech himself or written words. Wernicke thus concluded that this area was involved in speech comprehension and the disorder held by the patient came to be known as [[Wernicke's aphasia|fluent aphasia]]. The most common characteristics of Wernicke's aphasia include the capability of speech at a normal rate but with the insertion of nonsensical words, and word substitutions (paraphasias). Wernicke's aphasia also includes a severe comprehension deficit that affects the understanding of both spoken and written language as well as fluent and grammatically correct but nonsensical speech and writing.

Wernicke is also attributed to the discovery of one other form of aphasia, conduction aphasia. In conduction aphasia, the patient is capable of understanding speech but is incapable of repeating anything spoken to them. Conduction aphasics also tend to perform paraphasias, and sometimes even rearrange the phonemes of a word.

== References ==

Margaret Alic "Wernicke, Carl (1848-1905)". Encyclopedia of Psychology.

Stirling, J. (2002). ''Introducing neuropsychology''. Hove: Psychology Press.

[[Category:Neuropsychological profiles]]

Broca's area

2008-04-25T04:23:53Z

Cwhitehead:

[[Category:Brain areas]]
'''Broca's area''' is the area in the brain that is responsible for speech production, language processing, and language comprehension. Broca's area was first discovered in 1861 by Pierre [[Paul Broca]], after studying the postmortem brain of Monsieur LeBorgne, commonly known as Tan, a patient of his who had a speech impediment.

== Description ==
Broca's area is located in the left frontal lobe, around the opercular and triangular sections of the inferior frontal gyrus. It is connected to Wernicke’s area of the brain by the arcuate fasciculus, which is a pathway made of neurons. (see below).

[[Image:Broca.jpg]]

== Parts ==
Broca's area contains two main parts: the ''Pars triangularis'' and the ''Pars opercularis''.

The '''Pars triangularis''' is located in the anterior part of Broca's area. Researchers believe that this area of the brain is responsible for helping the human brain interpret different stimulus modes. It also supports the programming of verbal conducts.

The '''Pars opercularis''' is located in the posterior part of Broca's area. It is believed that this area supports only one stimulus mode, rather than multiple modes like the Pars triangularis. This portion of Broca’s area is also believed to coordinate the organs used for speech in order to produce language.

== Damage to Broca's area ==
If Broca's area is damaged, people will usually suffer from a condition called ''[[Broca's aphasia]]''. This condition is also sometimes called ''expressive aphasia'', ''nonfluent aphasia'', or ''motor aphasia''. Broca's aphasia makes people unable to create sentences that are grammatically complex. In addition, the sentences usually contain very few words related to content. Broca's aphasia is characterized by nonfluent speech, few words, short sentences, and many pauses.

For example, if a Broca's aphasic was trying to explain how he came to the hospital for dental surgery, it might sound like this:

"Yes... ah... Monday... er... Dad and Peter H... (his own name), and Dad.... er... hospital... and ah... Wednesday... Wednesday, nine o'clock... and oh... Thursday... ten o'clock, ah doctors... two... an' doctors... and er... teeth... yah."

Despite the Broca's aphasic's difficulty in putting together sentences, a person with a damaged Broca's area is generally capable of comprehending language without a problem. Sometimes, however, the person may have difficulty with understanding a few words used in a sentence with complex syntax. These people typically have damage only in the posterior part of Broca's area, a condition called ''[[Wernicke’s aphasia]]''. Those suffering from Wernicke’s aphasia may have somewhat normal speech, though it tends to be vague or even meaningless.

== Video Clip ==
[http://www.youtube.com/watch?v=iuPeOKeCxu8 Broca's area video]

Standard issue moral judgment interview

2008-04-25T04:20:24Z

Cwhitehead:

[[Category:Neuropsychological methods]]

The standard issue moral judgment interview was developed in 1958 by Lawerence Kohlberg.

During the moral judgment interview the interviewer uses moral dilemmas to determine which

stage of moral reasoning a person uses. The dilemmas are fictional short stories that describe

situations in which a person has to make a moral decision. Kohlberg believes that the

justifaction for the answer given by the participant is most important. The standard issue moral

judgment interview has six stages. The preconventional level which is most common in children.

The preconventional level judges the morality of an action by its direct consequences stage one

obedience and punishment orientation-how to avoid punishment and stage two self-interest

orientation-what's in it for me. The conventional level is typical in adolescents and adults.

Stage three interpersonal accord and conformity-the individual tries to be a good boy or a good

girl and stage four authority and social order obedience-importance to obey laws to maintain

society. The post conventional stage is also known as the principle level. Stage five social

context driven-realization that individuals have different opinions and values and stage six

universal ethical principles-reasoning is based on abstract reasoning.

Middle temporal cortex (V5)

2008-04-25T03:43:58Z

Cwhitehead:

[[Category:Brain areas]]

The middle temporal cortex deals with language, memory processing, visual perception and sensory

integration. Patients with schizophrenia usually have deficits in this part of the brain as well

as the inferior temporal lobe. The middle temporal cortex is an area in primates that has direct

and indirect input from the primary visual cortex.

Tan (aphasia patient)

2008-04-25T02:35:28Z

Cwhitehead:

[[Category:Neuropsychological profiles]]

In 1861 Paul Broca a neurologist first described what has become know as Broca's aphasia. Paul

Broca's patient Monsieur Leborgne led him to the discovery of broca's aphasia. Broca's aphasia is

known as an expressive, nonfluent, or motor aphasia. Broca's aphasia deals with a severe

nonfluency of speech which may cause the patient to be mute. In most cases speech is limited to

a few stereotyped expressions or expletives and patient's with less severe affects of broca's

aphasia may be able to answer questions with one word answers. Monsieur Leborgne is commonly referred

to as Tan because it is the only utterance he could make. Tan had a lesion in his third frontal

gyrus which controls motor speech and movement of the tongue, lips and vocal cords. Tan was

admitted to Bicetre Hospital when he was 21 when he suffered from a stroke, lost use of his

speech and became paralyzed on the right side of his body. Tan was Broca's first patient and in

1861 Tan died from widespread gangrene. After Tan's death Broca removed his brain and completed

a post mortem examination to pin point the exact location of Tan's lesions which Broca first

called aphemie which was later named aphasia.

Tan (aphasia patient)

2008-04-25T02:19:12Z

Cwhitehead:

[[Category:Neuropsychological profiles]]

In 1861 Paul Broca a neurologist first described what has become know as Broca's aphasia. Paul

Broca's patient M. Leborgne led him to the discovery of broca's aphasia. Broca's aphasia is

known as an expressive, nonfluent, or motor aphasia. Broca's aphasia deals with a severe

nonfluency of speech which may cause the patient to be mute. In most cases speech is limited to

a few stereotyped expressions or expletives and patient's with less severe affects of broca's

aphasia may be able to answer questions with one word answers. M. Leborgne is commonly referred

to as Tan because it is the only utterance he could make. Tan had a lesion in his third frontal

gyrus which controls motor speech and movement of the tongue, lips and vocal cords. Tan was

admitted to Bicetre Hospital when he was 21 when he suffered from a stroke, lost use of his

speech and became paralyzed on the right side of his body. Tan was Broca's first patient and in

1861 Tan died from widespread gangrene. After Tan's death Broca removed his brain and completed

a post mortem examination to pin point the exact location of Tan's lesions which Broca first

called aphemie which was later named aphasia.

Prosopagnosia

2008-04-24T23:27:43Z

Cwhitehead:

[[Category:Neuropsychological syndromes]]

Agnosia disorders include various cognitive disorders that deal with "not knowing impariments

such as auditory agnosia which is the inability to recognize sounds or visual object agnosia

which is the inability to recognize familar objects that can be seen. Visual object agnosia

is similar to prosopagnosia and most patients with visual object agnosia also have

prosopagnosia. Prosopagnosia is the inability to recognize faces on sight and is usually

associated with bilateral occipital damage. A patient named Michael was diagnosed with

prosopagnosia and a few other agnosia disorders. Michael is incapable of recognizing any faces

desipte the familiarity and he has not been able to for 17 years. He never recognizes his mother

until she speaks and when asked to identify himself in family photos he is incapable of doing

so. He does have the ability to recollect faces if asked to describe someone famous or a family

member yet when presented with a picture of that person he still is not able to recognize their

face or to identify the person by picture.

Prosopagnosia

2008-04-24T23:23:36Z

Cwhitehead:

[[Category:Neuropsychological syndromes]]

Agnosia disorders include various cognitive disorders that deal with "not knowing impariments

such as auditory agnosia which is the inability to recognize sounds or visual object agnosia

which is the inability to recognize familar objects that can be seen. Visual object agnosia is

similar to prosopagnosia and most patients with visual object agnosia also have prosopagnosia.

Prosopagnosia is the inability to recognize faces on sight and is usually associated with

bilateral occipital damage. A patient named Michael was diagnosed with prosopagnosia and a few

other agnosia disorders. Michael is incapable of recognizing any faces desipte the familiarity

and he has not been able to for 17 years. He never recognizes his mother until she speaks and

when asked to identify himself in family photos he is incapable of doing so. He does have the

ability to recollect faces if asked to describe someone famous or a family member yet when

presented with a picture of that person he still is not able to recognize their face or to

identify the person by picture.