Proper name anomia and anomia for the names of people: functionally dissociable impairments?

The central role of the left inferior longitudinal fasciculus in the face-name retrieval network

Unsuccessful retrieval of proper names (PNs) is commonly observed in patients suffering from neurological conditions such as stroke or epilepsy. While a large body of works has suggested that PN retrieval relies on a cortical network centered on the left anterior temporal lobe (ATL), much less is known about the white matter connections underpinning this process. Sparse studies provided evidence for a possible role of the uncinate fasciculus, but the inferior longitudinal fasciculus (ILF) might also contribute, since it mainly projects into the ATL, interconnects it with the posterior lexical interface and is engaged in common name (CN) retrieval. To ascertain this hypothesis, we assessed 58 patients having undergone a neurosurgery for a left low-grade glioma by means of a famous face naming (FFN) task. The behavioural data were processed following a multilevel lesion approach, including location-based analyses, voxel-based lesion-symptom mapping (VLSM) and disconnection-symptom mapping. Different statistical models were generated to control for sociodemographic data, familiarity, biographical knowledge and control cognitive performances (i.e., semantic and episodic memory and CN retrieval). Overall, VLSM analyses indicated that damage to the mid-to-anterior part of the ventro-basal temporal cortex was especially associated with PN retrieval deficits. As expected, tract-oriented analyses showed that the left ILF was the most strongly associated pathway. Our results provide evidence for the pivotal role of the ILF in the PN retrieval network. This novel finding paves the way for a better understanding of the pathophysiological bases underlying PN retrieval difficulties in the various neurological conditions marked by white matter abnormalities.

Proper names and personal identity

The present chapter reviews the body of knowledge acquired so far about the role of the temporal lobe in representing and processing proper names and individual identity information. This body of knowledge has been collected with the contribution of several methodologies, including neuroimaging, electrophysiological techniques, and, critically, clinical observations. All this evidence converges in showing that proper names and related information are processed in at least partially independent neural networks mainly placed in the anterior areas of the left temporal lobe. A description of the properties distinguishing proper names from common names is provided. These properties, it will be claimed, made a different anatomical organization necessary and, possibly, determined the evolution of the brain to support this advantageous distinction in meeting environmental demands.

Neural correlates of recognition and naming of famous persons and landmarks: A special role for the left anterior temporal lobe

The anterior temporal lobes (ATLs) have been shown to be crucial for recognition and naming of unique entities such as persons and places. In this chapter, we review previous research that identified the neural underpinnings of these processes, and discuss the convergence zone theory of conceptual knowledge and proper name retrieval. Lesion-deficit and neuroimaging studies have found that the temporal poles are essential for recognition and naming of unique persons and places. Research has shown laterality, in that the right anterior temporal pole is specialized for recognition and the left for naming. Here, we analyzed recognition and naming of persons and landmarks in a large neurologic sample (N=244) using the Iowa Famous Faces and Famous Landmarks tests. For both categories, education had a significant effect on recognition and naming performances, but age and gender did not. Lesion-symptom maps revealed lower naming scores for both Faces and Landmarks associated with lesions to the anterior and mesial left temporal lobe. Lower recognition scores were also linked to left temporal lobe damage, possibly due to the method we used for measuring recognition (verbally based). Overall, the results demonstrate the importance of the temporal lobes for recognition and naming of unique persons and places.

The cognitive psychology and neuroscience of naming people

The use of proper names enables us to designate entities, including people, at a very specific level of categorization: the unique entity or the individual. The paper presents a general overview of psychological/cognitive and neuroscientific studies that have compared the production of proper names, in particular people's names, with the production of common nouns during the last thirty years. The search for specific brain correlates of proper naming included single-case and group studies of patients with brain lesions, and studies utilizing functional neuroimaging or brain electrical stimulation with healthy participants. These studies have led neuroscientists to hypothesize that the recall of proper names involves a rather complex network including mainly left frontal and temporal regions. Behavioural evidence supports the view that proper names are more difficult to recall than common names, and scientists have proposed different explanations for this relative difficulty. Finally, several new directions for future research are proposed to improve our understanding of both cognitive processes and their brain correlates involved during proper name recall.

Why are names of people associated with so many phonological retrieval failures?

Two experiments are reported that revisit the issue of why people's names are more difficult to recall than common names such as the names of objects. In Experiment 1, retrieval of the names of a set of object pictures was compared with recall of a set of names of famous faces. The object and face sets were matched for preexperimental familiarity. The results showed significantly more tip-of-the tongue (TOT) states and significantly poorer name recall for faces than for objects. Although the overall numbers of incorrect answers for the two sets of items did not differ, the incorrect answers in the face condition were mostly "don't know" responses, whereas incorrect answers for objects were mostly alternative names. In Experiment 2, written definitions were used instead of pictures, and target items were selected so as to keep the number of alternatives to a minimum. Under these circumstances, there were no differences in either the number of items correctly named or the number of TOTs for common and people's names. These findings are consistent with the views of Brédart (Memory, 1, 351-366, 1993), who argued that there are fewer documented TOTs for common names because a semantically related alternative often comes to mind when a participant is experiencing, or is about to experience, a retrieval failure.

Recognition and naming of famous buildings: Italian normative data

Semantically unique items are concrete entities characterized by a unique cluster of semantic information. In this field, neuropsychology has always given more attention to faces than to other kind of stimuli. An important category that has been largely neglected so far is famous buildings. A total of 200 healthy Italian adults with age, sex and education homogenously distributed across subgroups were administered a famous buildings naming and recognition test, which assessed both visual and verbal modalities. The test was divided in seven sections; norms were calculated taking into account demographic variables such as age, sex and education. Multiple regression analyses showed that education influenced significantly the performance on all subtests; age had a significant effect for five subtests; sex for three subtests. Adjusted scores were used to determine inferential cutoff scores and to compute equivalent scores.

Partial knowledge in a tip-of-the-tongue state about two- and three-word proper names

Participants in this study attempted to name 44 famous people i n response to reading biographical information about them. Half of the celebrities had names that contained two words (e.g., Gwyneth Paltrow and Sean Penn), and half of them had names containing three words (e.g., Catherine Zeta Jones and Billy Bob Thornton). Half of the names had previously been judged to be of high familiarity (e.g., Gwyneth Paltrow), and half were of lower familiarity (e.g., Billy Bob Thornton). The results showed that when in a tip-of-the-tongue (TOT) state, the participants were able to estimate at above-chance rates whether a celebrity's name comprised two or three words. Accurate information about the number of words was not available to the participants unless they were in a TOT state or had already named the person. Attempts to identify celebrities whose name had three elements were associated with an increased number of TOTs, relative to celebrities whose name had two units, but there was no difference in the number of don't know responses for names containing two or three words. Calculations based on Gollan and Brown (2006) suggested that having three names impaired the phonological but not the semantic stage of lexical retrieval, whereas low familiarity impaired both semantic and phonological retrieval stages.

Naming of objects, faces and buildings in mild cognitive impairment

Accruing evidence suggests that the cognitive deficits in very early Alzheimer's Disease (AD) are not confined to episodic memory, with a number of studies documenting semantic memory deficits, especially for knowledge of people. To investigate whether this difficulty in naming famous people extends to other proper names based information, three naming tasks - the Graded Naming Test (GNT), which uses objects and animals, the Graded Faces Test (GFT) and the newly designed Graded Buildings Test (GBT) - were administered to 69 participants (32 patients in the early prodromal stage of AD, so-called Mild Cognitive Impairment (MCI), and 37 normal control participants). Patients were found to be impaired on all three tests compared to controls, although naming of objects was significantly better than naming of faces and buildings. Discriminant analysis successfully predicted group membership for 100% controls and 78.1% of patients. The results suggest that even in cases that do not yet fulfil criteria for AD naming of famous people and buildings is impaired, and that both these semantic domains show greater vulnerability than general semantic knowledge. A semantic deficit together with the hallmark episodic deficit may be common in MCI, and that the use of graded tasks tapping semantic memory may be useful for the early identification of patients with MCI.

Migraine aura and related phenomena: beyond scotomata and scintillations

Migraine affects the cortical physiology and may induce dysfunction both ictally and interictally. Although visual symptoms predominate during aura, other contiguous cortical areas related to less impressive symptoms are also impaired in migraine. Answers from 72.2% migraine with aura and 48.6% of migraine without aura patients on human faces and objects recognition, colour perception, proper names recalling and memory in general showed dysfunctions suggestive of prosopagnosia, dyschromatopsia, ideational apraxia, alien hand syndrome, proper name anomia or aphasia, varying in duration and severity. Symptoms frequently occurred in a successively building-up pattern fitting with the geographical distribution of the various cortical functions. When specifically inquired, migraineurs reveal less evident symptoms that are not usually considered during routine examination. Spreading depression most likely underlies the aura symptoms progression. Interictal involvement indicates that MWA and MWoA are not completely silent outside attacks, and that both subforms of migraine may share common mechanisms.

A test for measuring recognition and naming of landmarks

There have been considerable giants in recent years in understanding cognitive and neural correlated for retrieval of various types of knowledge, such as the meanings and lexical forms for categories such as a familiar faces, animals and tools, and actions. An important category that has been largely neglected so far is landmarks, and one likely reason for this is a lack of suitable stimulus materials. Here, we report a study in which we designed a Landmark Recognition and Naming Test. The test contains 65 natural (e.g., "Old Faithful") and artifactual (e.g., "U.S Capitol") landmarks from around the world. Preliminary recognition and naming data about the participants (e.g., educational level, participants, experience traveling to national parks), the stimuli (e.g., visual complexity, image agreement), and participant-stimulus interactions (e.g., familiarity, age of acquisition), and analyzed how such factors influenced landmark recognition and naming. There was a pronounced sex-related difference in landmark recognition favoring men; however, men and women performed similarly in landmark naming. We provide here extensive data regarding the stimuli, and we encourage other investigators to make use of our stimuli and data in future investigations of landmark recognition and naming.

Cross-Modality Priming for People's Adjectivized Names: Failure to Support the Adjectivization Hypothesis

This experiment tested a prediction derived from Hollis and Valentine's 2001 adjectivization hypothesis, that having an adjectival form is the key factor that makes certain classes of proper names, i.e., country names, exhibit a common name-like pattern of long-term priming. The hypothesis predicted that, when adjectivized historical celebrity names, e.g., William Shakespeare/Shakespearean, were compared with nonadjectivized historical celebrity names, e.g., Emile Zola, cross-modality long-term priming in a familiarity decision task would occur only for nonadjectivized name stimuli. 32 students of literature, history, or philosophy (21 women and 11 men; age range 18–41 years, M age = 22.4 yr.) were tested. Priming was measured by latency of response. Analysis showed that the mean RT to primed items was faster than the mean RT to unprimed items when the prime task was presented in both visual and auditory modalities both for the adjectivized and nonadjectivized names. Contrary to the hypothesis, cross-modality priming was observed regardless of the adjectivization of name stimuli. The findings of the present experiment did not support the adjectivization hypothesis.

Dissociating person-specific from general semantic knowledge: roles of the left and right temporal lobes

The cognitive architecture and neural underpinnings of different semantic domains remains highly controversial. We report two patients with focal temporal lobe atrophy who presented with contrasting and theoretically informative dissociations of person-specific versus general semantic knowledge. Subject J.P. showed severely impaired person-specific semantics, with relative preservation of knowledge about objects and animals, while subject M.A. exhibited the opposite pattern of performance (good knowledge of people in the context of impoverished general semantics). Voxel-based morphometric analysis of MR images in the two cases established predominantly right temporal atrophy associated with J.P.'s deficit for person knowledge and predominantly left temporal atrophy in M.A. who was impaired in general conceptual knowledge.

Anomia for common names and geographical names with preserved retrieval of names of people: a semantic memory disorder

This paper describes the case of an anomic patient (FH) who is impaired at naming pictures of objects but has no difficulties in recalling the names of familiar people. Even though his performance on McKenna's (1997) Category Specific Naming Test was at the first percentile, he consistently recalled the names of familiar people as successfully as controls. It is argued that the pattern of performance displayed by FH represents a much clearer double dissociation with proper name anomia than any case previously reported (Cipolotti et al., 1993; Semenza and Sgaramella, 1993). FH is unable to provide detailed semantic information about many of the objects that he cannot name, even though he can recall semantic information about familiar people. Consequently his case appears to represent the mirror image of the proper name anomic patient (APA) described by Miceli et al. (2000) who was unable to recall detailed semantic information about many of the people she was unable to name. Further investigation of FH's anomia revealed impairments in retrieving both common nouns and verbs, and difficulties in retrieving and comprehending geographical names. It is argued that FH's preserved ability to name and recall biographical information about people supports the view that knowledge about familiar people may be subserved by its own dedicated neural subsystem (Kay and Hanley, 1999; Miceli et al., 2000; Gentileschi et al., 2001).

Exploring the relationship between proper name anomia and word retrieval: a single case study

We report the results of an investigation of the spoken word retrieval abilities of a patient, BG, with proper name anomia. Our investigations reveal that she is impaired in retrieving common nouns as well as proper names. Common noun retrieval was influenced by age-of-acquisition, word familiarity and name agreement. Cued retrieval of proper names was influenced by age-of-acquisition, although effects of other linguistic variables were not excluded. It is claimed that an explanation in terms of a 'continuum of word retrieval difficulty' rather than of proper names as 'pure referring expressions' can best account for the findings. However, this proposal is unlikely to be able to explain all cases of proper name anomia. Nonetheless, it is suggested that similar findings may be observed in other people with proper name anomia, and that it is necessary for future studies to investigate not only proper name but also common noun retrieval. We also provide evidence that Plausible Phonology and Specificity hypotheses of proper name anomia cannot account for BG's naming abilities.

Cerebral laterality for famous proper nouns: visual recognition by normal subjects

Lexical processing has long been associated with left-hemisphere function, especially for infrequently occurring words. Recently, however, persons with severe aphasia, including word-recognition deficits, were observed to recognize familiar proper nouns. Further, some patients suffering right-hemisphere damage were poorer at identifying famous names than left-hemisphere-damaged subjects. These observations point to the possibility that some property of the right hemisphere provides an advantage for the processing of familiar or personally relevant stimuli. To investigate this possibility, we conducted split-visual-field studies in which we manipulated stimulus sets, recognition task, and exposure duration. Greater accuracy in the right visual field was found for common nouns and unknown proper nouns, and famous proper nouns were overall more accurately recognized. Performance for famous nouns in the two visual fields was not significantly different when the task required categorization into famous or nonfamous and when stimuli most highly rated as familiar were used. These findings support our proposals that (1) both hemispheres can process famous proper nouns and (2) the right hemisphere is specialized for personal relevance.

The nature of the disorder underlying the inability to retrieve proper names

Two patients with the syndrome of proper name anomia were investigated. Both patients were only able to produce around 50% of the names of contemporary celebrities, but performed significantly better on a task calling for naming of historical figures. The names of relatives and friends were spared in one patient, while the other retrieved names of people known since childhood much better than those of people familiar to him since the age of 25. Geographical names, names of monuments and masterpieces were preserved. The above dissociations are taken to imply that in moderately impaired patients, a temporal gradient effect concurs to modulate the severity of the naming block. A similar impairment was found in both patients when they attempted to retrieve or relearn familiar telephone numbers. This finding suggests that the core of the disorder resides in the inability to gain access to words used to identify a single entity, regardless of whether they belong to the class of proper or common names.