• A distinct expressive syndrome could thus arise from selective damage (line 1) to the output store located in Broca's area, while a receptive syndrome could arise from selective damage (line 2) to the input store (located in what is now known as Wernicke's area). • The differentiation between receptive and expressive difficulties was entailed by the model on the basis of information flow among component information transducers, as well as, but independently from the anatomical locale of the components. • These 'disconnection' syndromes required new tests to reveal quite a different set of critical symptoms, where a symptom is as importantly as a spared function as a deficit. • The fundamental point here is the overall pattern of deficient and spared functions. Historically, the most important symptom was the impairment or the sparing of repetition. • The model held that there existed a subcortical connexion between the auditory word images in Wernicke's area and the motor word images in Broca's area that mediated the exact repetition of heard speech, the lesioning of which (line 3) would lead to deficits on this task without other receptive or expressive difficulties. • A repetition impairment, even if it had been tested previously, would have been quite obscure without this model; a selective sparing of repetition in the absence of comprehension or volitional speech in the 'transcortical’ syndromes would have been even more obscure. • The model of the cortical speech centres developed by Lichtheim on the basis of Wernicke’s proposals has become known as the Wernicke-Lichtheim model. • These modifications were based on Lichtheim’s observations of two new aphasic syndromes. One type, now called transcortical sensory aphasia, is characterized by a reduced ability to comprehend speech similar to that observed with Wernicke’s aphasia and pure word deafness. • The patients with transcortical sensory aphasia are also fluent but have trouble expressing their thoughts. • However, unlike patients with Wernicke’s aphasia and pure word deafness, who cannot repeat or imitate speech, patients with transcortical sensory aphasia can repeat normally. • Thus, when a person hears another person speak, after auditory analysis (in Heschl’s gyrus), auditory information is passed to Wernicke’s area, where the representations of word sounds are activated and after these phonological word representations are activated this information is transmitted to the areas of the brain where concepts are elaborated (conceptual-semantic field). • Lichtheim suggested that when a person wants to speak, they activate these conceptual-semantic representations and these conceptual representations directly access and activate Broca’s area (Fig. pathway G).

1. UNIT 3
MODELS OF LANGUAGE PROCESSING:
(Lichtheim’s Model, Logogen Model, Micro Genetic Model)
Submitted to Submitted by
DR. SATISH K. HIMANI BANSAL
MVSCOSH MASLP IInd year

2. LICHTHEIM MODEL
(1885):

3. LOGOGEN MODEL (MORTON,1969):

4. INTERACTIVE ACTIVATION MODEL
(RUMELHART AND MCCLELLAND ,1981, 82):

5. SEIDENBERG & McCLELLAND
MODEL
(1989):

6. DUAL- ROUTE MODEL:

7. MICROGENETIC MODEL (SIEGLER
AND CROWLEY ,1983):
Direct mean for studying the cognitive development
It involves observation of individual children throughout
the period of change, a density of observations relative
to the rate of change within that period and intensive
trial by trial analysis intended to infer the processes that
give rise to the change
Helpful for investigating the interactions through which
teachers and learners, or learners working together
acquire new competencies; but it is difficult and time
consuming to conduct

8. REFERENCES:
1. https://opentextbc.ca/psyclanguage/chapter/reading-models/
2. https://en.wikipedia.org/wiki/Logogen_model#:~:text=The%20logogen%20model%20of%2
01969,to%20recognize%20one%20specific%20word
3. http://kunnampallilgejo.blogspot.com/search?q=logogen+model
QUESTIONS ASKED IN PREVIOUS
YEARS:
1. Describe the Logogen model of language processing – 16 Marks (2021)
2. Short notes on: Logogen model & Micro genetic model – 4 Marks each
(2019, 2014, 2013, 2012, 2011)

9. THANKYOU